DBD-SQLite-Amalgamation
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sqlite-amalgamation.c view on Meta::CPAN
*/
SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff);
/*
** CAPI3REF: Automatically Load An Extensions {H12640} <S20500>
**
** This API can be invoked at program startup in order to register
** one or more statically linked extensions that will be available
** to all new [database connections]. {END}
**
** This routine stores a pointer to the extension in an array that is
** obtained from [sqlite3_malloc()]. If you run a memory leak checker
** on your program and it reports a leak because of this array, invoke
** [sqlite3_reset_auto_extension()] prior to shutdown to free the memory.
**
** {H12641} This function registers an extension entry point that is
** automatically invoked whenever a new [database connection]
** is opened using [sqlite3_open()], [sqlite3_open16()],
** or [sqlite3_open_v2()].
**
** {H12642} Duplicate extensions are detected so calling this routine
** multiple times with the same extension is harmless.
**
** {H12643} This routine stores a pointer to the extension in an array
** that is obtained from [sqlite3_malloc()].
**
** {H12644} Automatic extensions apply across all threads.
*/
SQLITE_API int sqlite3_auto_extension(void *xEntryPoint);
/*
** CAPI3REF: Reset Automatic Extension Loading {H12660} <S20500>
**
** This function disables all previously registered automatic
** extensions. {END} It undoes the effect of all prior
** [sqlite3_auto_extension()] calls.
**
** {H12661} This function disables all previously registered
** automatic extensions.
**
** {H12662} This function disables automatic extensions in all threads.
*/
SQLITE_API void sqlite3_reset_auto_extension(void);
/*
****** EXPERIMENTAL - subject to change without notice **************
**
** The interface to the virtual-table mechanism is currently considered
** to be experimental. The interface might change in incompatible ways.
** If this is a problem for you, do not use the interface at this time.
**
** When the virtual-table mechanism stabilizes, we will declare the
** interface fixed, support it indefinitely, and remove this comment.
*/
/*
** Structures used by the virtual table interface
*/
typedef struct sqlite3_vtab sqlite3_vtab;
typedef struct sqlite3_index_info sqlite3_index_info;
typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor;
typedef struct sqlite3_module sqlite3_module;
/*
** CAPI3REF: Virtual Table Object {H18000} <S20400>
** KEYWORDS: sqlite3_module
** EXPERIMENTAL
**
** A module is a class of virtual tables. Each module is defined
** by an instance of the following structure. This structure consists
** mostly of methods for the module.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
struct sqlite3_module {
int iVersion;
int (*xCreate)(sqlite3*, void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVTab, char**);
int (*xConnect)(sqlite3*, void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVTab, char**);
int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*);
int (*xDisconnect)(sqlite3_vtab *pVTab);
int (*xDestroy)(sqlite3_vtab *pVTab);
int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor);
int (*xClose)(sqlite3_vtab_cursor*);
int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr,
int argc, sqlite3_value **argv);
int (*xNext)(sqlite3_vtab_cursor*);
int (*xEof)(sqlite3_vtab_cursor*);
int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int);
int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid);
int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *);
int (*xBegin)(sqlite3_vtab *pVTab);
int (*xSync)(sqlite3_vtab *pVTab);
int (*xCommit)(sqlite3_vtab *pVTab);
int (*xRollback)(sqlite3_vtab *pVTab);
int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName,
void (**pxFunc)(sqlite3_context*,int,sqlite3_value**),
void **ppArg);
int (*xRename)(sqlite3_vtab *pVtab, const char *zNew);
};
/*
** CAPI3REF: Virtual Table Indexing Information {H18100} <S20400>
** KEYWORDS: sqlite3_index_info
** EXPERIMENTAL
**
** The sqlite3_index_info structure and its substructures is used to
** pass information into and receive the reply from the xBestIndex
** method of an sqlite3_module. The fields under **Inputs** are the
** inputs to xBestIndex and are read-only. xBestIndex inserts its
** results into the **Outputs** fields.
**
** The aConstraint[] array records WHERE clause constraints of the form:
**
** <pre>column OP expr</pre>
**
** where OP is =, <, <=, >, or >=. The particular operator is
** stored in aConstraint[].op. The index of the column is stored in
** aConstraint[].iColumn. aConstraint[].usable is TRUE if the
** expr on the right-hand side can be evaluated (and thus the constraint
** is usable) and false if it cannot.
**
** The optimizer automatically inverts terms of the form "expr OP column"
** and makes other simplifications to the WHERE clause in an attempt to
** get as many WHERE clause terms into the form shown above as possible.
** The aConstraint[] array only reports WHERE clause terms in the correct
** form that refer to the particular virtual table being queried.
**
** Information about the ORDER BY clause is stored in aOrderBy[].
** Each term of aOrderBy records a column of the ORDER BY clause.
**
** The xBestIndex method must fill aConstraintUsage[] with information
** about what parameters to pass to xFilter. If argvIndex>0 then
** the right-hand side of the corresponding aConstraint[] is evaluated
** and becomes the argvIndex-th entry in argv. If aConstraintUsage[].omit
** is true, then the constraint is assumed to be fully handled by the
** virtual table and is not checked again by SQLite.
**
** The idxNum and idxPtr values are recorded and passed into xFilter.
** sqlite3_free() is used to free idxPtr if needToFreeIdxPtr is true.
**
** The orderByConsumed means that output from xFilter will occur in
** the correct order to satisfy the ORDER BY clause so that no separate
** sorting step is required.
**
** The estimatedCost value is an estimate of the cost of doing the
** particular lookup. A full scan of a table with N entries should have
** a cost of N. A binary search of a table of N entries should have a
** cost of approximately log(N).
**
sqlite-amalgamation.c view on Meta::CPAN
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
SQLITE_API int sqlite3_create_module(
sqlite3 *db, /* SQLite connection to register module with */
const char *zName, /* Name of the module */
const sqlite3_module *, /* Methods for the module */
void * /* Client data for xCreate/xConnect */
);
/*
** CAPI3REF: Register A Virtual Table Implementation {H18210} <S20400>
** EXPERIMENTAL
**
** This routine is identical to the [sqlite3_create_module()] method above,
** except that it allows a destructor function to be specified. It is
** even more experimental than the rest of the virtual tables API.
*/
SQLITE_API int sqlite3_create_module_v2(
sqlite3 *db, /* SQLite connection to register module with */
const char *zName, /* Name of the module */
const sqlite3_module *, /* Methods for the module */
void *, /* Client data for xCreate/xConnect */
void(*xDestroy)(void*) /* Module destructor function */
);
/*
** CAPI3REF: Virtual Table Instance Object {H18010} <S20400>
** KEYWORDS: sqlite3_vtab
** EXPERIMENTAL
**
** Every module implementation uses a subclass of the following structure
** to describe a particular instance of the module. Each subclass will
** be tailored to the specific needs of the module implementation.
** The purpose of this superclass is to define certain fields that are
** common to all module implementations.
**
** Virtual tables methods can set an error message by assigning a
** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should
** take care that any prior string is freed by a call to [sqlite3_free()]
** prior to assigning a new string to zErrMsg. After the error message
** is delivered up to the client application, the string will be automatically
** freed by sqlite3_free() and the zErrMsg field will be zeroed. Note
** that sqlite3_mprintf() and sqlite3_free() are used on the zErrMsg field
** since virtual tables are commonly implemented in loadable extensions which
** do not have access to sqlite3MPrintf() or sqlite3Free().
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
struct sqlite3_vtab {
const sqlite3_module *pModule; /* The module for this virtual table */
int nRef; /* Used internally */
char *zErrMsg; /* Error message from sqlite3_mprintf() */
/* Virtual table implementations will typically add additional fields */
};
/*
** CAPI3REF: Virtual Table Cursor Object {H18020} <S20400>
** KEYWORDS: sqlite3_vtab_cursor
** EXPERIMENTAL
**
** Every module implementation uses a subclass of the following structure
** to describe cursors that point into the virtual table and are used
** to loop through the virtual table. Cursors are created using the
** xOpen method of the module. Each module implementation will define
** the content of a cursor structure to suit its own needs.
**
** This superclass exists in order to define fields of the cursor that
** are common to all implementations.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
struct sqlite3_vtab_cursor {
sqlite3_vtab *pVtab; /* Virtual table of this cursor */
/* Virtual table implementations will typically add additional fields */
};
/*
** CAPI3REF: Declare The Schema Of A Virtual Table {H18280} <S20400>
** EXPERIMENTAL
**
** The xCreate and xConnect methods of a module use the following API
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
**
** This interface is experimental and is subject to change or
** removal in future releases of SQLite.
*/
SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zCreateTable);
/*
** CAPI3REF: Overload A Function For A Virtual Table {H18300} <S20400>
** EXPERIMENTAL
**
** Virtual tables can provide alternative implementations of functions
** using the xFindFunction method. But global versions of those functions
** must exist in order to be overloaded.
**
** This API makes sure a global version of a function with a particular
** name and number of parameters exists. If no such function exists
** before this API is called, a new function is created. The implementation
** of the new function always causes an exception to be thrown. So
** the new function is not good for anything by itself. Its only
** purpose is to be a placeholder function that can be overloaded
** by virtual tables.
**
** This API should be considered part of the virtual table interface,
** which is experimental and subject to change.
*/
SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg);
/*
** The interface to the virtual-table mechanism defined above (back up
** to a comment remarkably similar to this one) is currently considered
** to be experimental. The interface might change in incompatible ways.
** If this is a problem for you, do not use the interface at this time.
**
** When the virtual-table mechanism stabilizes, we will declare the
** interface fixed, support it indefinitely, and remove this comment.
**
****** EXPERIMENTAL - subject to change without notice **************
*/
/*
** CAPI3REF: A Handle To An Open BLOB {H17800} <S30230>
** KEYWORDS: {BLOB handle} {BLOB handles}
**
** An instance of this object represents an open BLOB on which
** [sqlite3_blob_open | incremental BLOB I/O] can be performed.
** Objects of this type are created by [sqlite3_blob_open()]
** and destroyed by [sqlite3_blob_close()].
** The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces
** can be used to read or write small subsections of the BLOB.
** The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.
sqlite-amalgamation.c view on Meta::CPAN
#define BTREE_OMIT_JOURNAL 1 /* Do not use journal. No argument */
#define BTREE_NO_READLOCK 2 /* Omit readlocks on readonly files */
#define BTREE_MEMORY 4 /* In-memory DB. No argument */
#define BTREE_READONLY 8 /* Open the database in read-only mode */
#define BTREE_READWRITE 16 /* Open for both reading and writing */
#define BTREE_CREATE 32 /* Create the database if it does not exist */
SQLITE_PRIVATE int sqlite3BtreeClose(Btree*);
SQLITE_PRIVATE int sqlite3BtreeSetCacheSize(Btree*,int);
SQLITE_PRIVATE int sqlite3BtreeSetSafetyLevel(Btree*,int,int);
SQLITE_PRIVATE int sqlite3BtreeSyncDisabled(Btree*);
SQLITE_PRIVATE int sqlite3BtreeSetPageSize(Btree*,int,int);
SQLITE_PRIVATE int sqlite3BtreeGetPageSize(Btree*);
SQLITE_PRIVATE int sqlite3BtreeMaxPageCount(Btree*,int);
SQLITE_PRIVATE int sqlite3BtreeGetReserve(Btree*);
SQLITE_PRIVATE int sqlite3BtreeSetAutoVacuum(Btree *, int);
SQLITE_PRIVATE int sqlite3BtreeGetAutoVacuum(Btree *);
SQLITE_PRIVATE int sqlite3BtreeBeginTrans(Btree*,int);
SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree*, const char *zMaster);
SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree*);
SQLITE_PRIVATE int sqlite3BtreeCommit(Btree*);
SQLITE_PRIVATE int sqlite3BtreeRollback(Btree*);
SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree*);
SQLITE_PRIVATE int sqlite3BtreeCommitStmt(Btree*);
SQLITE_PRIVATE int sqlite3BtreeRollbackStmt(Btree*);
SQLITE_PRIVATE int sqlite3BtreeCreateTable(Btree*, int*, int flags);
SQLITE_PRIVATE int sqlite3BtreeIsInTrans(Btree*);
SQLITE_PRIVATE int sqlite3BtreeIsInStmt(Btree*);
SQLITE_PRIVATE int sqlite3BtreeIsInReadTrans(Btree*);
SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *, int, void(*)(void *));
SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *);
SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *, int, u8);
SQLITE_PRIVATE const char *sqlite3BtreeGetFilename(Btree *);
SQLITE_PRIVATE const char *sqlite3BtreeGetDirname(Btree *);
SQLITE_PRIVATE const char *sqlite3BtreeGetJournalname(Btree *);
SQLITE_PRIVATE int sqlite3BtreeCopyFile(Btree *, Btree *);
SQLITE_PRIVATE int sqlite3BtreeIncrVacuum(Btree *);
/* The flags parameter to sqlite3BtreeCreateTable can be the bitwise OR
** of the following flags:
*/
#define BTREE_INTKEY 1 /* Table has only 64-bit signed integer keys */
#define BTREE_ZERODATA 2 /* Table has keys only - no data */
#define BTREE_LEAFDATA 4 /* Data stored in leaves only. Implies INTKEY */
SQLITE_PRIVATE int sqlite3BtreeDropTable(Btree*, int, int*);
SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree*, int);
SQLITE_PRIVATE int sqlite3BtreeGetMeta(Btree*, int idx, u32 *pValue);
SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree*, int idx, u32 value);
SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree*, int);
struct UnpackedRecord; /* Forward declaration. Definition in vdbeaux.c. */
SQLITE_PRIVATE int sqlite3BtreeCursor(
Btree*, /* BTree containing table to open */
int iTable, /* Index of root page */
int wrFlag, /* 1 for writing. 0 for read-only */
struct KeyInfo*, /* First argument to compare function */
BtCursor *pCursor /* Space to write cursor structure */
);
SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeMoveto(
BtCursor*,
const void *pKey,
struct UnpackedRecord *pUnKey,
i64 nKey,
int bias,
int *pRes
);
SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*, int*);
SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeInsert(BtCursor*, const void *pKey, i64 nKey,
const void *pData, int nData,
int nZero, int bias);
SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeFlags(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor*, int *pRes);
SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor*, i64 *pSize);
SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE sqlite3 *sqlite3BtreeCursorDb(const BtCursor*);
SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor*, int *pAmt);
SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor*, int *pAmt);
SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor*, u32 *pSize);
SQLITE_PRIVATE int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*);
SQLITE_PRIVATE struct Pager *sqlite3BtreePager(Btree*);
SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*);
SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *);
#ifdef SQLITE_TEST
SQLITE_PRIVATE int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
SQLITE_PRIVATE void sqlite3BtreeCursorList(Btree*);
#endif
/*
** If we are not using shared cache, then there is no need to
** use mutexes to access the BtShared structures. So make the
** Enter and Leave procedures no-ops.
*/
#if !defined(SQLITE_OMIT_SHARED_CACHE) && SQLITE_THREADSAFE
SQLITE_PRIVATE void sqlite3BtreeEnter(Btree*);
SQLITE_PRIVATE void sqlite3BtreeLeave(Btree*);
#ifndef NDEBUG
/* This routine is used inside assert() statements only. */
SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree*);
#endif
SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor*);
SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor*);
SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3*);
SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3*);
#ifndef NDEBUG
/* This routine is used inside assert() statements only. */
sqlite-amalgamation.c view on Meta::CPAN
/*
** Column affinity types.
**
** These used to have mnemonic name like 'i' for SQLITE_AFF_INTEGER and
** 't' for SQLITE_AFF_TEXT. But we can save a little space and improve
** the speed a little by number the values consecutively.
**
** But rather than start with 0 or 1, we begin with 'a'. That way,
** when multiple affinity types are concatenated into a string and
** used as the P4 operand, they will be more readable.
**
** Note also that the numeric types are grouped together so that testing
** for a numeric type is a single comparison.
*/
#define SQLITE_AFF_TEXT 'a'
#define SQLITE_AFF_NONE 'b'
#define SQLITE_AFF_NUMERIC 'c'
#define SQLITE_AFF_INTEGER 'd'
#define SQLITE_AFF_REAL 'e'
#define sqlite3IsNumericAffinity(X) ((X)>=SQLITE_AFF_NUMERIC)
/*
** The SQLITE_AFF_MASK values masks off the significant bits of an
** affinity value.
*/
#define SQLITE_AFF_MASK 0x67
/*
** Additional bit values that can be ORed with an affinity without
** changing the affinity.
*/
#define SQLITE_JUMPIFNULL 0x08 /* jumps if either operand is NULL */
#define SQLITE_STOREP2 0x10 /* Store result in reg[P2] rather than jump */
/*
** Each SQL table is represented in memory by an instance of the
** following structure.
**
** Table.zName is the name of the table. The case of the original
** CREATE TABLE statement is stored, but case is not significant for
** comparisons.
**
** Table.nCol is the number of columns in this table. Table.aCol is a
** pointer to an array of Column structures, one for each column.
**
** If the table has an INTEGER PRIMARY KEY, then Table.iPKey is the index of
** the column that is that key. Otherwise Table.iPKey is negative. Note
** that the datatype of the PRIMARY KEY must be INTEGER for this field to
** be set. An INTEGER PRIMARY KEY is used as the rowid for each row of
** the table. If a table has no INTEGER PRIMARY KEY, then a random rowid
** is generated for each row of the table. Table.hasPrimKey is true if
** the table has any PRIMARY KEY, INTEGER or otherwise.
**
** Table.tnum is the page number for the root BTree page of the table in the
** database file. If Table.iDb is the index of the database table backend
** in sqlite.aDb[]. 0 is for the main database and 1 is for the file that
** holds temporary tables and indices. If Table.isEphem
** is true, then the table is stored in a file that is automatically deleted
** when the VDBE cursor to the table is closed. In this case Table.tnum
** refers VDBE cursor number that holds the table open, not to the root
** page number. Transient tables are used to hold the results of a
** sub-query that appears instead of a real table name in the FROM clause
** of a SELECT statement.
*/
struct Table {
sqlite3 *db; /* Associated database connection. Might be NULL. */
char *zName; /* Name of the table */
int nCol; /* Number of columns in this table */
Column *aCol; /* Information about each column */
int iPKey; /* If not less then 0, use aCol[iPKey] as the primary key */
Index *pIndex; /* List of SQL indexes on this table. */
int tnum; /* Root BTree node for this table (see note above) */
Select *pSelect; /* NULL for tables. Points to definition if a view. */
int nRef; /* Number of pointers to this Table */
Trigger *pTrigger; /* List of SQL triggers on this table */
FKey *pFKey; /* Linked list of all foreign keys in this table */
char *zColAff; /* String defining the affinity of each column */
#ifndef SQLITE_OMIT_CHECK
Expr *pCheck; /* The AND of all CHECK constraints */
#endif
#ifndef SQLITE_OMIT_ALTERTABLE
int addColOffset; /* Offset in CREATE TABLE statement to add a new column */
#endif
u8 readOnly; /* True if this table should not be written by the user */
u8 isEphem; /* True if created using OP_OpenEphermeral */
u8 hasPrimKey; /* True if there exists a primary key */
u8 keyConf; /* What to do in case of uniqueness conflict on iPKey */
u8 autoInc; /* True if the integer primary key is autoincrement */
#ifndef SQLITE_OMIT_VIRTUALTABLE
u8 isVirtual; /* True if this is a virtual table */
u8 isCommit; /* True once the CREATE TABLE has been committed */
Module *pMod; /* Pointer to the implementation of the module */
sqlite3_vtab *pVtab; /* Pointer to the module instance */
int nModuleArg; /* Number of arguments to the module */
char **azModuleArg; /* Text of all module args. [0] is module name */
#endif
Schema *pSchema; /* Schema that contains this table */
};
/*
** Test to see whether or not a table is a virtual table. This is
** done as a macro so that it will be optimized out when virtual
** table support is omitted from the build.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
# define IsVirtual(X) ((X)->isVirtual)
# define IsHiddenColumn(X) ((X)->isHidden)
#else
# define IsVirtual(X) 0
# define IsHiddenColumn(X) 0
#endif
/*
** Each foreign key constraint is an instance of the following structure.
**
** A foreign key is associated with two tables. The "from" table is
** the table that contains the REFERENCES clause that creates the foreign
** key. The "to" table is the table that is named in the REFERENCES clause.
** Consider this example:
**
sqlite-amalgamation.c view on Meta::CPAN
** If Expr.op==TK_AGG_COLUMN or TK_AGG_FUNCTION then Expr.pAggInfo is a
** pointer to this structure. The Expr.iColumn field is the index in
** AggInfo.aCol[] or AggInfo.aFunc[] of information needed to generate
** code for that node.
**
** AggInfo.pGroupBy and AggInfo.aFunc.pExpr point to fields within the
** original Select structure that describes the SELECT statement. These
** fields do not need to be freed when deallocating the AggInfo structure.
*/
struct AggInfo {
u8 directMode; /* Direct rendering mode means take data directly
** from source tables rather than from accumulators */
u8 useSortingIdx; /* In direct mode, reference the sorting index rather
** than the source table */
int sortingIdx; /* Cursor number of the sorting index */
ExprList *pGroupBy; /* The group by clause */
int nSortingColumn; /* Number of columns in the sorting index */
struct AggInfo_col { /* For each column used in source tables */
Table *pTab; /* Source table */
int iTable; /* Cursor number of the source table */
int iColumn; /* Column number within the source table */
int iSorterColumn; /* Column number in the sorting index */
int iMem; /* Memory location that acts as accumulator */
Expr *pExpr; /* The original expression */
} *aCol;
int nColumn; /* Number of used entries in aCol[] */
int nColumnAlloc; /* Number of slots allocated for aCol[] */
int nAccumulator; /* Number of columns that show through to the output.
** Additional columns are used only as parameters to
** aggregate functions */
struct AggInfo_func { /* For each aggregate function */
Expr *pExpr; /* Expression encoding the function */
FuncDef *pFunc; /* The aggregate function implementation */
int iMem; /* Memory location that acts as accumulator */
int iDistinct; /* Ephermeral table used to enforce DISTINCT */
} *aFunc;
int nFunc; /* Number of entries in aFunc[] */
int nFuncAlloc; /* Number of slots allocated for aFunc[] */
};
/*
** Each node of an expression in the parse tree is an instance
** of this structure.
**
** Expr.op is the opcode. The integer parser token codes are reused
** as opcodes here. For example, the parser defines TK_GE to be an integer
** code representing the ">=" operator. This same integer code is reused
** to represent the greater-than-or-equal-to operator in the expression
** tree.
**
** Expr.pRight and Expr.pLeft are subexpressions. Expr.pList is a list
** of argument if the expression is a function.
**
** Expr.token is the operator token for this node. For some expressions
** that have subexpressions, Expr.token can be the complete text that gave
** rise to the Expr. In the latter case, the token is marked as being
** a compound token.
**
** An expression of the form ID or ID.ID refers to a column in a table.
** For such expressions, Expr.op is set to TK_COLUMN and Expr.iTable is
** the integer cursor number of a VDBE cursor pointing to that table and
** Expr.iColumn is the column number for the specific column. If the
** expression is used as a result in an aggregate SELECT, then the
** value is also stored in the Expr.iAgg column in the aggregate so that
** it can be accessed after all aggregates are computed.
**
** If the expression is a function, the Expr.iTable is an integer code
** representing which function. If the expression is an unbound variable
** marker (a question mark character '?' in the original SQL) then the
** Expr.iTable holds the index number for that variable.
**
** If the expression is a subquery then Expr.iColumn holds an integer
** register number containing the result of the subquery. If the
** subquery gives a constant result, then iTable is -1. If the subquery
** gives a different answer at different times during statement processing
** then iTable is the address of a subroutine that computes the subquery.
**
** The Expr.pSelect field points to a SELECT statement. The SELECT might
** be the right operand of an IN operator. Or, if a scalar SELECT appears
** in an expression the opcode is TK_SELECT and Expr.pSelect is the only
** operand.
**
** If the Expr is of type OP_Column, and the table it is selecting from
** is a disk table or the "old.*" pseudo-table, then pTab points to the
** corresponding table definition.
*/
struct Expr {
u8 op; /* Operation performed by this node */
char affinity; /* The affinity of the column or 0 if not a column */
u16 flags; /* Various flags. See below */
CollSeq *pColl; /* The collation type of the column or 0 */
Expr *pLeft, *pRight; /* Left and right subnodes */
ExprList *pList; /* A list of expressions used as function arguments
** or in "<expr> IN (<expr-list)" */
Token token; /* An operand token */
Token span; /* Complete text of the expression */
int iTable, iColumn; /* When op==TK_COLUMN, then this expr node means the
** iColumn-th field of the iTable-th table. */
AggInfo *pAggInfo; /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */
int iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
int iRightJoinTable; /* If EP_FromJoin, the right table of the join */
Select *pSelect; /* When the expression is a sub-select. Also the
** right side of "<expr> IN (<select>)" */
Table *pTab; /* Table for OP_Column expressions. */
#if SQLITE_MAX_EXPR_DEPTH>0
int nHeight; /* Height of the tree headed by this node */
#endif
};
/*
** The following are the meanings of bits in the Expr.flags field.
*/
#define EP_FromJoin 0x0001 /* Originated in ON or USING clause of a join */
#define EP_Agg 0x0002 /* Contains one or more aggregate functions */
#define EP_Resolved 0x0004 /* IDs have been resolved to COLUMNs */
#define EP_Error 0x0008 /* Expression contains one or more errors */
#define EP_Distinct 0x0010 /* Aggregate function with DISTINCT keyword */
#define EP_VarSelect 0x0020 /* pSelect is correlated, not constant */
#define EP_Dequoted 0x0040 /* True if the string has been dequoted */
#define EP_InfixFunc 0x0080 /* True for an infix function: LIKE, GLOB, etc */
#define EP_ExpCollate 0x0100 /* Collating sequence specified explicitly */
sqlite-amalgamation.c view on Meta::CPAN
/*
** An instance of this structure can hold a simple list of identifiers,
** such as the list "a,b,c" in the following statements:
**
** INSERT INTO t(a,b,c) VALUES ...;
** CREATE INDEX idx ON t(a,b,c);
** CREATE TRIGGER trig BEFORE UPDATE ON t(a,b,c) ...;
**
** The IdList.a.idx field is used when the IdList represents the list of
** column names after a table name in an INSERT statement. In the statement
**
** INSERT INTO t(a,b,c) ...
**
** If "a" is the k-th column of table "t", then IdList.a[0].idx==k.
*/
struct IdList {
struct IdList_item {
char *zName; /* Name of the identifier */
int idx; /* Index in some Table.aCol[] of a column named zName */
} *a;
int nId; /* Number of identifiers on the list */
int nAlloc; /* Number of entries allocated for a[] below */
};
/*
** The bitmask datatype defined below is used for various optimizations.
**
** Changing this from a 64-bit to a 32-bit type limits the number of
** tables in a join to 32 instead of 64. But it also reduces the size
** of the library by 738 bytes on ix86.
*/
typedef u64 Bitmask;
/*
** The following structure describes the FROM clause of a SELECT statement.
** Each table or subquery in the FROM clause is a separate element of
** the SrcList.a[] array.
**
** With the addition of multiple database support, the following structure
** can also be used to describe a particular table such as the table that
** is modified by an INSERT, DELETE, or UPDATE statement. In standard SQL,
** such a table must be a simple name: ID. But in SQLite, the table can
** now be identified by a database name, a dot, then the table name: ID.ID.
**
** The jointype starts out showing the join type between the current table
** and the next table on the list. The parser builds the list this way.
** But sqlite3SrcListShiftJoinType() later shifts the jointypes so that each
** jointype expresses the join between the table and the previous table.
*/
struct SrcList {
i16 nSrc; /* Number of tables or subqueries in the FROM clause */
i16 nAlloc; /* Number of entries allocated in a[] below */
struct SrcList_item {
char *zDatabase; /* Name of database holding this table */
char *zName; /* Name of the table */
char *zAlias; /* The "B" part of a "A AS B" phrase. zName is the "A" */
Table *pTab; /* An SQL table corresponding to zName */
Select *pSelect; /* A SELECT statement used in place of a table name */
u8 isPopulated; /* Temporary table associated with SELECT is populated */
u8 jointype; /* Type of join between this able and the previous */
int iCursor; /* The VDBE cursor number used to access this table */
Expr *pOn; /* The ON clause of a join */
IdList *pUsing; /* The USING clause of a join */
Bitmask colUsed; /* Bit N (1<<N) set if column N or pTab is used */
} a[1]; /* One entry for each identifier on the list */
};
/*
** Permitted values of the SrcList.a.jointype field
*/
#define JT_INNER 0x0001 /* Any kind of inner or cross join */
#define JT_CROSS 0x0002 /* Explicit use of the CROSS keyword */
#define JT_NATURAL 0x0004 /* True for a "natural" join */
#define JT_LEFT 0x0008 /* Left outer join */
#define JT_RIGHT 0x0010 /* Right outer join */
#define JT_OUTER 0x0020 /* The "OUTER" keyword is present */
#define JT_ERROR 0x0040 /* unknown or unsupported join type */
/*
** For each nested loop in a WHERE clause implementation, the WhereInfo
** structure contains a single instance of this structure. This structure
** is intended to be private the the where.c module and should not be
** access or modified by other modules.
**
** The pIdxInfo and pBestIdx fields are used to help pick the best
** index on a virtual table. The pIdxInfo pointer contains indexing
** information for the i-th table in the FROM clause before reordering.
** All the pIdxInfo pointers are freed by whereInfoFree() in where.c.
** The pBestIdx pointer is a copy of pIdxInfo for the i-th table after
** FROM clause ordering. This is a little confusing so I will repeat
** it in different words. WhereInfo.a[i].pIdxInfo is index information
** for WhereInfo.pTabList.a[i]. WhereInfo.a[i].pBestInfo is the
** index information for the i-th loop of the join. pBestInfo is always
** either NULL or a copy of some pIdxInfo. So for cleanup it is
** sufficient to free all of the pIdxInfo pointers.
**
*/
struct WhereLevel {
int iFrom; /* Which entry in the FROM clause */
int flags; /* Flags associated with this level */
int iMem; /* First memory cell used by this level */
int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */
Index *pIdx; /* Index used. NULL if no index */
int iTabCur; /* The VDBE cursor used to access the table */
int iIdxCur; /* The VDBE cursor used to acesss pIdx */
int brk; /* Jump here to break out of the loop */
int nxt; /* Jump here to start the next IN combination */
int cont; /* Jump here to continue with the next loop cycle */
int top; /* First instruction of interior of the loop */
int op, p1, p2; /* Opcode used to terminate the loop */
int nEq; /* Number of == or IN constraints on this loop */
int nIn; /* Number of IN operators constraining this loop */
struct InLoop {
int iCur; /* The VDBE cursor used by this IN operator */
int topAddr; /* Top of the IN loop */
} *aInLoop; /* Information about each nested IN operator */
sqlite3_index_info *pBestIdx; /* Index information for this level */
/* The following field is really not part of the current level. But
** we need a place to cache index information for each table in the
** FROM clause and the WhereLevel structure is a convenient place.
*/
sqlite3_index_info *pIdxInfo; /* Index info for n-th source table */
};
/*
** Flags appropriate for the wflags parameter of sqlite3WhereBegin().
*/
#define WHERE_ORDERBY_NORMAL 0 /* No-op */
#define WHERE_ORDERBY_MIN 1 /* ORDER BY processing for min() func */
#define WHERE_ORDERBY_MAX 2 /* ORDER BY processing for max() func */
#define WHERE_ONEPASS_DESIRED 4 /* Want to do one-pass UPDATE/DELETE */
/*
** The WHERE clause processing routine has two halves. The
** first part does the start of the WHERE loop and the second
** half does the tail of the WHERE loop. An instance of
** this structure is returned by the first half and passed
** into the second half to give some continuity.
*/
struct WhereInfo {
Parse *pParse; /* Parsing and code generating context */
u8 okOnePass; /* Ok to use one-pass algorithm for UPDATE or DELETE */
SrcList *pTabList; /* List of tables in the join */
int iTop; /* The very beginning of the WHERE loop */
int iContinue; /* Jump here to continue with next record */
int iBreak; /* Jump here to break out of the loop */
int nLevel; /* Number of nested loop */
sqlite3_index_info **apInfo; /* Array of pointers to index info structures */
WhereLevel a[1]; /* Information about each nest loop in the WHERE */
};
/*
** A NameContext defines a context in which to resolve table and column
** names. The context consists of a list of tables (the pSrcList) field and
** a list of named expression (pEList). The named expression list may
** be NULL. The pSrc corresponds to the FROM clause of a SELECT or
** to the table being operated on by INSERT, UPDATE, or DELETE. The
** pEList corresponds to the result set of a SELECT and is NULL for
** other statements.
**
** NameContexts can be nested. When resolving names, the inner-most
** context is searched first. If no match is found, the next outer
** context is checked. If there is still no match, the next context
** is checked. This process continues until either a match is found
** or all contexts are check. When a match is found, the nRef member of
** the context containing the match is incremented.
**
** Each subquery gets a new NameContext. The pNext field points to the
** NameContext in the parent query. Thus the process of scanning the
** NameContext list corresponds to searching through successively outer
** subqueries looking for a match.
*/
struct NameContext {
sqlite-amalgamation.c view on Meta::CPAN
#define SRT_Union 1 /* Store result as keys in an index */
#define SRT_Except 2 /* Remove result from a UNION index */
#define SRT_Exists 3 /* Store 1 if the result is not empty */
#define SRT_Discard 4 /* Do not save the results anywhere */
/* The ORDER BY clause is ignored for all of the above */
#define IgnorableOrderby(X) ((X->eDest)<=SRT_Discard)
#define SRT_Callback 5 /* Invoke a callback with each row of result */
#define SRT_Mem 6 /* Store result in a memory cell */
#define SRT_Set 7 /* Store results as keys in an index */
#define SRT_Table 8 /* Store result as data with an automatic rowid */
#define SRT_EphemTab 9 /* Create transient tab and store like SRT_Table */
#define SRT_Coroutine 10 /* Generate a single row of result */
/*
** A structure used to customize the behaviour of sqlite3Select(). See
** comments above sqlite3Select() for details.
*/
typedef struct SelectDest SelectDest;
struct SelectDest {
u8 eDest; /* How to dispose of the results */
u8 affinity; /* Affinity used when eDest==SRT_Set */
int iParm; /* A parameter used by the eDest disposal method */
int iMem; /* Base register where results are written */
int nMem; /* Number of registers allocated */
};
/*
** An SQL parser context. A copy of this structure is passed through
** the parser and down into all the parser action routine in order to
** carry around information that is global to the entire parse.
**
** The structure is divided into two parts. When the parser and code
** generate call themselves recursively, the first part of the structure
** is constant but the second part is reset at the beginning and end of
** each recursion.
**
** The nTableLock and aTableLock variables are only used if the shared-cache
** feature is enabled (if sqlite3Tsd()->useSharedData is true). They are
** used to store the set of table-locks required by the statement being
** compiled. Function sqlite3TableLock() is used to add entries to the
** list.
*/
struct Parse {
sqlite3 *db; /* The main database structure */
int rc; /* Return code from execution */
char *zErrMsg; /* An error message */
Vdbe *pVdbe; /* An engine for executing database bytecode */
u8 colNamesSet; /* TRUE after OP_ColumnName has been issued to pVdbe */
u8 nameClash; /* A permanent table name clashes with temp table name */
u8 checkSchema; /* Causes schema cookie check after an error */
u8 nested; /* Number of nested calls to the parser/code generator */
u8 parseError; /* True after a parsing error. Ticket #1794 */
u8 nTempReg; /* Number of temporary registers in aTempReg[] */
u8 nTempInUse; /* Number of aTempReg[] currently checked out */
int aTempReg[8]; /* Holding area for temporary registers */
int nRangeReg; /* Size of the temporary register block */
int iRangeReg; /* First register in temporary register block */
int nErr; /* Number of errors seen */
int nTab; /* Number of previously allocated VDBE cursors */
int nMem; /* Number of memory cells used so far */
int nSet; /* Number of sets used so far */
int ckBase; /* Base register of data during check constraints */
int disableColCache; /* True to disable adding to column cache */
int nColCache; /* Number of entries in the column cache */
int iColCache; /* Next entry of the cache to replace */
struct yColCache {
int iTable; /* Table cursor number */
int iColumn; /* Table column number */
char affChange; /* True if this register has had an affinity change */
int iReg; /* Register holding value of this column */
} aColCache[10]; /* One for each valid column cache entry */
u32 writeMask; /* Start a write transaction on these databases */
u32 cookieMask; /* Bitmask of schema verified databases */
int cookieGoto; /* Address of OP_Goto to cookie verifier subroutine */
int cookieValue[SQLITE_MAX_ATTACHED+2]; /* Values of cookies to verify */
#ifndef SQLITE_OMIT_SHARED_CACHE
int nTableLock; /* Number of locks in aTableLock */
TableLock *aTableLock; /* Required table locks for shared-cache mode */
#endif
int regRowid; /* Register holding rowid of CREATE TABLE entry */
int regRoot; /* Register holding root page number for new objects */
/* Above is constant between recursions. Below is reset before and after
** each recursion */
int nVar; /* Number of '?' variables seen in the SQL so far */
int nVarExpr; /* Number of used slots in apVarExpr[] */
int nVarExprAlloc; /* Number of allocated slots in apVarExpr[] */
Expr **apVarExpr; /* Pointers to :aaa and $aaaa wildcard expressions */
u8 explain; /* True if the EXPLAIN flag is found on the query */
Token sErrToken; /* The token at which the error occurred */
Token sNameToken; /* Token with unqualified schema object name */
Token sLastToken; /* The last token parsed */
const char *zSql; /* All SQL text */
const char *zTail; /* All SQL text past the last semicolon parsed */
Table *pNewTable; /* A table being constructed by CREATE TABLE */
Trigger *pNewTrigger; /* Trigger under construct by a CREATE TRIGGER */
TriggerStack *trigStack; /* Trigger actions being coded */
const char *zAuthContext; /* The 6th parameter to db->xAuth callbacks */
#ifndef SQLITE_OMIT_VIRTUALTABLE
Token sArg; /* Complete text of a module argument */
u8 declareVtab; /* True if inside sqlite3_declare_vtab() */
int nVtabLock; /* Number of virtual tables to lock */
Table **apVtabLock; /* Pointer to virtual tables needing locking */
#endif
int nHeight; /* Expression tree height of current sub-select */
};
#ifdef SQLITE_OMIT_VIRTUALTABLE
#define IN_DECLARE_VTAB 0
#else
#define IN_DECLARE_VTAB (pParse->declareVtab)
#endif
/*
** An instance of the following structure can be declared on a stack and used
** to save the Parse.zAuthContext value so that it can be restored later.
*/
struct AuthContext {
const char *zAuthContext; /* Put saved Parse.zAuthContext here */
Parse *pParse; /* The Parse structure */
};
/*
** Bitfield flags for P2 value in OP_Insert and OP_Delete
*/
#define OPFLAG_NCHANGE 1 /* Set to update db->nChange */
sqlite-amalgamation.c view on Meta::CPAN
* An instance of struct TriggerStep is used to store a single SQL statement
* that is a part of a trigger-program.
*
* Instances of struct TriggerStep are stored in a singly linked list (linked
* using the "pNext" member) referenced by the "step_list" member of the
* associated struct Trigger instance. The first element of the linked list is
* the first step of the trigger-program.
*
* The "op" member indicates whether this is a "DELETE", "INSERT", "UPDATE" or
* "SELECT" statement. The meanings of the other members is determined by the
* value of "op" as follows:
*
* (op == TK_INSERT)
* orconf -> stores the ON CONFLICT algorithm
* pSelect -> If this is an INSERT INTO ... SELECT ... statement, then
* this stores a pointer to the SELECT statement. Otherwise NULL.
* target -> A token holding the name of the table to insert into.
* pExprList -> If this is an INSERT INTO ... VALUES ... statement, then
* this stores values to be inserted. Otherwise NULL.
* pIdList -> If this is an INSERT INTO ... (<column-names>) VALUES ...
* statement, then this stores the column-names to be
* inserted into.
*
* (op == TK_DELETE)
* target -> A token holding the name of the table to delete from.
* pWhere -> The WHERE clause of the DELETE statement if one is specified.
* Otherwise NULL.
*
* (op == TK_UPDATE)
* target -> A token holding the name of the table to update rows of.
* pWhere -> The WHERE clause of the UPDATE statement if one is specified.
* Otherwise NULL.
* pExprList -> A list of the columns to update and the expressions to update
* them to. See sqlite3Update() documentation of "pChanges"
* argument.
*
*/
struct TriggerStep {
int op; /* One of TK_DELETE, TK_UPDATE, TK_INSERT, TK_SELECT */
int orconf; /* OE_Rollback etc. */
Trigger *pTrig; /* The trigger that this step is a part of */
Select *pSelect; /* Valid for SELECT and sometimes
INSERT steps (when pExprList == 0) */
Token target; /* Valid for DELETE, UPDATE, INSERT steps */
Expr *pWhere; /* Valid for DELETE, UPDATE steps */
ExprList *pExprList; /* Valid for UPDATE statements and sometimes
INSERT steps (when pSelect == 0) */
IdList *pIdList; /* Valid for INSERT statements only */
TriggerStep *pNext; /* Next in the link-list */
TriggerStep *pLast; /* Last element in link-list. Valid for 1st elem only */
};
/*
* An instance of struct TriggerStack stores information required during code
* generation of a single trigger program. While the trigger program is being
* coded, its associated TriggerStack instance is pointed to by the
* "pTriggerStack" member of the Parse structure.
*
* The pTab member points to the table that triggers are being coded on. The
* newIdx member contains the index of the vdbe cursor that points at the temp
* table that stores the new.* references. If new.* references are not valid
* for the trigger being coded (for example an ON DELETE trigger), then newIdx
* is set to -1. The oldIdx member is analogous to newIdx, for old.* references.
*
* The ON CONFLICT policy to be used for the trigger program steps is stored
* as the orconf member. If this is OE_Default, then the ON CONFLICT clause
* specified for individual triggers steps is used.
*
* struct TriggerStack has a "pNext" member, to allow linked lists to be
* constructed. When coding nested triggers (triggers fired by other triggers)
* each nested trigger stores its parent trigger's TriggerStack as the "pNext"
* pointer. Once the nested trigger has been coded, the pNext value is restored
* to the pTriggerStack member of the Parse stucture and coding of the parent
* trigger continues.
*
* Before a nested trigger is coded, the linked list pointed to by the
* pTriggerStack is scanned to ensure that the trigger is not about to be coded
* recursively. If this condition is detected, the nested trigger is not coded.
*/
struct TriggerStack {
Table *pTab; /* Table that triggers are currently being coded on */
int newIdx; /* Index of vdbe cursor to "new" temp table */
int oldIdx; /* Index of vdbe cursor to "old" temp table */
u32 newColMask;
u32 oldColMask;
int orconf; /* Current orconf policy */
int ignoreJump; /* where to jump to for a RAISE(IGNORE) */
Trigger *pTrigger; /* The trigger currently being coded */
TriggerStack *pNext; /* Next trigger down on the trigger stack */
};
/*
** The following structure contains information used by the sqliteFix...
** routines as they walk the parse tree to make database references
** explicit.
*/
typedef struct DbFixer DbFixer;
struct DbFixer {
Parse *pParse; /* The parsing context. Error messages written here */
const char *zDb; /* Make sure all objects are contained in this database */
const char *zType; /* Type of the container - used for error messages */
const Token *pName; /* Name of the container - used for error messages */
};
/*
** An objected used to accumulate the text of a string where we
** do not necessarily know how big the string will be in the end.
*/
struct StrAccum {
sqlite3 *db; /* Optional database for lookaside. Can be NULL */
char *zBase; /* A base allocation. Not from malloc. */
char *zText; /* The string collected so far */
int nChar; /* Length of the string so far */
int nAlloc; /* Amount of space allocated in zText */
int mxAlloc; /* Maximum allowed string length */
u8 mallocFailed; /* Becomes true if any memory allocation fails */
u8 useMalloc; /* True if zText is enlargable using realloc */
u8 tooBig; /* Becomes true if string size exceeds limits */
};
/*
** A pointer to this structure is used to communicate information
** from sqlite3Init and OP_ParseSchema into the sqlite3InitCallback.
*/
typedef struct {
sqlite3 *db; /* The database being initialized */
int iDb; /* 0 for main database. 1 for TEMP, 2.. for ATTACHed */
char **pzErrMsg; /* Error message stored here */
int rc; /* Result code stored here */
} InitData;
/*
** Structure containing global configuration data for the SQLite library.
**
** This structure also contains some state information.
*/
struct Sqlite3Config {
int bMemstat; /* True to enable memory status */
int bCoreMutex; /* True to enable core mutexing */
int bFullMutex; /* True to enable full mutexing */
int mxStrlen; /* Maximum string length */
int szLookaside; /* Default lookaside buffer size */
int nLookaside; /* Default lookaside buffer count */
sqlite-amalgamation.c view on Meta::CPAN
** 11110uuu 10uuzzzz 10yyyyyy 10xxxxxx 000uuuuu zzzzyyyy yyxxxxxx
**
**
** Notes on UTF-16: (with wwww+1==uuuuu)
**
** Word-0 Word-1 Value
** 110110ww wwzzzzyy 110111yy yyxxxxxx 000uuuuu zzzzyyyy yyxxxxxx
** zzzzyyyy yyxxxxxx 00000000 zzzzyyyy yyxxxxxx
**
**
** BOM or Byte Order Mark:
** 0xff 0xfe little-endian utf-16 follows
** 0xfe 0xff big-endian utf-16 follows
**
*/
/************** Include vdbeInt.h in the middle of utf.c *********************/
/************** Begin file vdbeInt.h *****************************************/
/*
** 2003 September 6
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This is the header file for information that is private to the
** VDBE. This information used to all be at the top of the single
** source code file "vdbe.c". When that file became too big (over
** 6000 lines long) it was split up into several smaller files and
** this header information was factored out.
**
** $Id: vdbeInt.h,v 1.153 2008/08/02 03:50:39 drh Exp $
*/
#ifndef _VDBEINT_H_
#define _VDBEINT_H_
/*
** intToKey() and keyToInt() used to transform the rowid. But with
** the latest versions of the design they are no-ops.
*/
#define keyToInt(X) (X)
#define intToKey(X) (X)
/*
** SQL is translated into a sequence of instructions to be
** executed by a virtual machine. Each instruction is an instance
** of the following structure.
*/
typedef struct VdbeOp Op;
/*
** Boolean values
*/
typedef unsigned char Bool;
/*
** A cursor is a pointer into a single BTree within a database file.
** The cursor can seek to a BTree entry with a particular key, or
** loop over all entries of the Btree. You can also insert new BTree
** entries or retrieve the key or data from the entry that the cursor
** is currently pointing to.
**
** Every cursor that the virtual machine has open is represented by an
** instance of the following structure.
**
** If the Cursor.isTriggerRow flag is set it means that this cursor is
** really a single row that represents the NEW or OLD pseudo-table of
** a row trigger. The data for the row is stored in Cursor.pData and
** the rowid is in Cursor.iKey.
*/
struct Cursor {
BtCursor *pCursor; /* The cursor structure of the backend */
int iDb; /* Index of cursor database in db->aDb[] (or -1) */
i64 lastRowid; /* Last rowid from a Next or NextIdx operation */
i64 nextRowid; /* Next rowid returned by OP_NewRowid */
Bool zeroed; /* True if zeroed out and ready for reuse */
Bool rowidIsValid; /* True if lastRowid is valid */
Bool atFirst; /* True if pointing to first entry */
Bool useRandomRowid; /* Generate new record numbers semi-randomly */
Bool nullRow; /* True if pointing to a row with no data */
Bool nextRowidValid; /* True if the nextRowid field is valid */
Bool pseudoTable; /* This is a NEW or OLD pseudo-tables of a trigger */
Bool ephemPseudoTable;
Bool deferredMoveto; /* A call to sqlite3BtreeMoveto() is needed */
Bool isTable; /* True if a table requiring integer keys */
Bool isIndex; /* True if an index containing keys only - no data */
u8 bogusIncrKey; /* Something for pIncrKey to point to if pKeyInfo==0 */
i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */
Btree *pBt; /* Separate file holding temporary table */
int nData; /* Number of bytes in pData */
char *pData; /* Data for a NEW or OLD pseudo-table */
i64 iKey; /* Key for the NEW or OLD pseudo-table row */
u8 *pIncrKey; /* Pointer to pKeyInfo->incrKey */
KeyInfo *pKeyInfo; /* Info about index keys needed by index cursors */
int nField; /* Number of fields in the header */
i64 seqCount; /* Sequence counter */
sqlite3_vtab_cursor *pVtabCursor; /* The cursor for a virtual table */
const sqlite3_module *pModule; /* Module for cursor pVtabCursor */
/* Cached information about the header for the data record that the
** cursor is currently pointing to. Only valid if cacheValid is true.
** aRow might point to (ephemeral) data for the current row, or it might
** be NULL.
*/
int cacheStatus; /* Cache is valid if this matches Vdbe.cacheCtr */
int payloadSize; /* Total number of bytes in the record */
u32 *aType; /* Type values for all entries in the record */
u32 *aOffset; /* Cached offsets to the start of each columns data */
u8 *aRow; /* Data for the current row, if all on one page */
};
typedef struct Cursor Cursor;
/*
** A value for Cursor.cacheValid that means the cache is always invalid.
*/
#define CACHE_STALE 0
/*
** Internally, the vdbe manipulates nearly all SQL values as Mem
** structures. Each Mem struct may cache multiple representations (string,
** integer etc.) of the same value. A value (and therefore Mem structure)
** has the following properties:
**
** Each value has a manifest type. The manifest type of the value stored
** in a Mem struct is returned by the MemType(Mem*) macro. The type is
** one of SQLITE_NULL, SQLITE_INTEGER, SQLITE_REAL, SQLITE_TEXT or
** SQLITE_BLOB.
*/
struct Mem {
union {
i64 i; /* Integer value. Or FuncDef* when flags==MEM_Agg */
FuncDef *pDef; /* Used only when flags==MEM_Agg */
} u;
double r; /* Real value */
sqlite3 *db; /* The associated database connection */
char *z; /* String or BLOB value */
int n; /* Number of characters in string value, excluding '\0' */
u16 flags; /* Some combination of MEM_Null, MEM_Str, MEM_Dyn, etc. */
u8 type; /* One of SQLITE_NULL, SQLITE_TEXT, SQLITE_INTEGER, etc */
u8 enc; /* SQLITE_UTF8, SQLITE_UTF16BE, SQLITE_UTF16LE */
void (*xDel)(void *); /* If not null, call this function to delete Mem.z */
char *zMalloc; /* Dynamic buffer allocated by sqlite3_malloc() */
};
/* One or more of the following flags are set to indicate the validOK
** representations of the value stored in the Mem struct.
**
** If the MEM_Null flag is set, then the value is an SQL NULL value.
** No other flags may be set in this case.
**
** If the MEM_Str flag is set then Mem.z points at a string representation.
** Usually this is encoded in the same unicode encoding as the main
** database (see below for exceptions). If the MEM_Term flag is also
** set, then the string is nul terminated. The MEM_Int and MEM_Real
** flags may coexist with the MEM_Str flag.
**
** Multiple of these values can appear in Mem.flags. But only one
** at a time can appear in Mem.type.
*/
#define MEM_Null 0x0001 /* Value is NULL */
#define MEM_Str 0x0002 /* Value is a string */
sqlite-amalgamation.c view on Meta::CPAN
i64 aSlot[1]; /* One or more slots for rowid values */
};
/*
** The Fifo structure is typedef-ed in vdbeInt.h. But the implementation
** of that structure is private to this file.
**
** The Fifo structure describes the entire fifo.
*/
typedef struct Fifo Fifo;
struct Fifo {
int nEntry; /* Total number of entries */
sqlite3 *db; /* The associated database connection */
FifoPage *pFirst; /* First page on the list */
FifoPage *pLast; /* Last page on the list */
};
/*
** A Context stores the last insert rowid, the last statement change count,
** and the current statement change count (i.e. changes since last statement).
** The current keylist is also stored in the context.
** Elements of Context structure type make up the ContextStack, which is
** updated by the ContextPush and ContextPop opcodes (used by triggers).
** The context is pushed before executing a trigger a popped when the
** trigger finishes.
*/
typedef struct Context Context;
struct Context {
i64 lastRowid; /* Last insert rowid (sqlite3.lastRowid) */
int nChange; /* Statement changes (Vdbe.nChanges) */
Fifo sFifo; /* Records that will participate in a DELETE or UPDATE */
};
/*
** An instance of the virtual machine. This structure contains the complete
** state of the virtual machine.
**
** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
** is really a pointer to an instance of this structure.
**
** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
** any virtual table method invocations made by the vdbe program. It is
** set to 2 for xDestroy method calls and 1 for all other methods. This
** variable is used for two purposes: to allow xDestroy methods to execute
** "DROP TABLE" statements and to prevent some nasty side effects of
** malloc failure when SQLite is invoked recursively by a virtual table
** method function.
*/
struct Vdbe {
sqlite3 *db; /* The whole database */
Vdbe *pPrev,*pNext; /* Linked list of VDBEs with the same Vdbe.db */
int nOp; /* Number of instructions in the program */
int nOpAlloc; /* Number of slots allocated for aOp[] */
Op *aOp; /* Space to hold the virtual machine's program */
int nLabel; /* Number of labels used */
int nLabelAlloc; /* Number of slots allocated in aLabel[] */
int *aLabel; /* Space to hold the labels */
Mem **apArg; /* Arguments to currently executing user function */
Mem *aColName; /* Column names to return */
int nCursor; /* Number of slots in apCsr[] */
Cursor **apCsr; /* One element of this array for each open cursor */
int nVar; /* Number of entries in aVar[] */
Mem *aVar; /* Values for the OP_Variable opcode. */
char **azVar; /* Name of variables */
int okVar; /* True if azVar[] has been initialized */
int magic; /* Magic number for sanity checking */
int nMem; /* Number of memory locations currently allocated */
Mem *aMem; /* The memory locations */
int nCallback; /* Number of callbacks invoked so far */
int cacheCtr; /* Cursor row cache generation counter */
Fifo sFifo; /* A list of ROWIDs */
int contextStackTop; /* Index of top element in the context stack */
int contextStackDepth; /* The size of the "context" stack */
Context *contextStack; /* Stack used by opcodes ContextPush & ContextPop*/
int pc; /* The program counter */
int rc; /* Value to return */
unsigned uniqueCnt; /* Used by OP_MakeRecord when P2!=0 */
int errorAction; /* Recovery action to do in case of an error */
int inTempTrans; /* True if temp database is transactioned */
int nResColumn; /* Number of columns in one row of the result set */
char **azResColumn; /* Values for one row of result */
char *zErrMsg; /* Error message written here */
Mem *pResultSet; /* Pointer to an array of results */
u8 explain; /* True if EXPLAIN present on SQL command */
u8 changeCntOn; /* True to update the change-counter */
u8 expired; /* True if the VM needs to be recompiled */
u8 minWriteFileFormat; /* Minimum file format for writable database files */
u8 inVtabMethod; /* See comments above */
int nChange; /* Number of db changes made since last reset */
i64 startTime; /* Time when query started - used for profiling */
int btreeMask; /* Bitmask of db->aDb[] entries referenced */
BtreeMutexArray aMutex; /* An array of Btree used here and needing locks */
int nSql; /* Number of bytes in zSql */
char *zSql; /* Text of the SQL statement that generated this */
#ifdef SQLITE_DEBUG
FILE *trace; /* Write an execution trace here, if not NULL */
#endif
int openedStatement; /* True if this VM has opened a statement journal */
#ifdef SQLITE_SSE
int fetchId; /* Statement number used by sqlite3_fetch_statement */
int lru; /* Counter used for LRU cache replacement */
#endif
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
Vdbe *pLruPrev;
Vdbe *pLruNext;
#endif
};
/*
** An instance of the following structure holds information about a
** single index record that has already been parsed out into individual
** values.
**
** A record is an object that contains one or more fields of data.
** Records are used to store the content of a table row and to store
** the key of an index. A blob encoding of a record is created by
** the OP_MakeRecord opcode of the VDBE and is disassemblied by the
** OP_Column opcode.
**
** This structure holds a record that has already been disassembled
** into its constitutent fields.
sqlite-amalgamation.c view on Meta::CPAN
** information about the page that is decoded from the raw file page.
**
** The pParent field points back to the parent page. This allows us to
** walk up the BTree from any leaf to the root. Care must be taken to
** unref() the parent page pointer when this page is no longer referenced.
** The pageDestructor() routine handles that chore.
**
** Access to all fields of this structure is controlled by the mutex
** stored in MemPage.pBt->mutex.
*/
struct MemPage {
u8 isInit; /* True if previously initialized. MUST BE FIRST! */
u8 idxShift; /* True if Cell indices have changed */
u8 nOverflow; /* Number of overflow cell bodies in aCell[] */
u8 intKey; /* True if intkey flag is set */
u8 leaf; /* True if leaf flag is set */
u8 hasData; /* True if this page stores data */
u8 hdrOffset; /* 100 for page 1. 0 otherwise */
u8 childPtrSize; /* 0 if leaf==1. 4 if leaf==0 */
u16 maxLocal; /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
u16 minLocal; /* Copy of BtShared.minLocal or BtShared.minLeaf */
u16 cellOffset; /* Index in aData of first cell pointer */
u16 idxParent; /* Index in parent of this node */
u16 nFree; /* Number of free bytes on the page */
u16 nCell; /* Number of cells on this page, local and ovfl */
u16 maskPage; /* Mask for page offset */
struct _OvflCell { /* Cells that will not fit on aData[] */
u8 *pCell; /* Pointers to the body of the overflow cell */
u16 idx; /* Insert this cell before idx-th non-overflow cell */
} aOvfl[5];
BtShared *pBt; /* Pointer to BtShared that this page is part of */
u8 *aData; /* Pointer to disk image of the page data */
DbPage *pDbPage; /* Pager page handle */
Pgno pgno; /* Page number for this page */
MemPage *pParent; /* The parent of this page. NULL for root */
};
/*
** The in-memory image of a disk page has the auxiliary information appended
** to the end. EXTRA_SIZE is the number of bytes of space needed to hold
** that extra information.
*/
#define EXTRA_SIZE sizeof(MemPage)
/* A Btree handle
**
** A database connection contains a pointer to an instance of
** this object for every database file that it has open. This structure
** is opaque to the database connection. The database connection cannot
** see the internals of this structure and only deals with pointers to
** this structure.
**
** For some database files, the same underlying database cache might be
** shared between multiple connections. In that case, each contection
** has it own pointer to this object. But each instance of this object
** points to the same BtShared object. The database cache and the
** schema associated with the database file are all contained within
** the BtShared object.
**
** All fields in this structure are accessed under sqlite3.mutex.
** The pBt pointer itself may not be changed while there exists cursors
** in the referenced BtShared that point back to this Btree since those
** cursors have to do go through this Btree to find their BtShared and
** they often do so without holding sqlite3.mutex.
*/
struct Btree {
sqlite3 *db; /* The database connection holding this btree */
BtShared *pBt; /* Sharable content of this btree */
u8 inTrans; /* TRANS_NONE, TRANS_READ or TRANS_WRITE */
u8 sharable; /* True if we can share pBt with another db */
u8 locked; /* True if db currently has pBt locked */
int wantToLock; /* Number of nested calls to sqlite3BtreeEnter() */
Btree *pNext; /* List of other sharable Btrees from the same db */
Btree *pPrev; /* Back pointer of the same list */
};
/*
** Btree.inTrans may take one of the following values.
**
** If the shared-data extension is enabled, there may be multiple users
** of the Btree structure. At most one of these may open a write transaction,
** but any number may have active read transactions.
*/
#define TRANS_NONE 0
#define TRANS_READ 1
#define TRANS_WRITE 2
/*
** An instance of this object represents a single database file.
**
** A single database file can be in use as the same time by two
** or more database connections. When two or more connections are
** sharing the same database file, each connection has it own
** private Btree object for the file and each of those Btrees points
** to this one BtShared object. BtShared.nRef is the number of
** connections currently sharing this database file.
**
** Fields in this structure are accessed under the BtShared.mutex
** mutex, except for nRef and pNext which are accessed under the
** global SQLITE_MUTEX_STATIC_MASTER mutex. The pPager field
** may not be modified once it is initially set as long as nRef>0.
** The pSchema field may be set once under BtShared.mutex and
** thereafter is unchanged as long as nRef>0.
*/
struct BtShared {
Pager *pPager; /* The page cache */
sqlite3 *db; /* Database connection currently using this Btree */
BtCursor *pCursor; /* A list of all open cursors */
MemPage *pPage1; /* First page of the database */
u8 inStmt; /* True if we are in a statement subtransaction */
u8 readOnly; /* True if the underlying file is readonly */
u8 pageSizeFixed; /* True if the page size can no longer be changed */
#ifndef SQLITE_OMIT_AUTOVACUUM
u8 autoVacuum; /* True if auto-vacuum is enabled */
u8 incrVacuum; /* True if incr-vacuum is enabled */
Pgno nTrunc; /* Non-zero if the db will be truncated (incr vacuum) */
#endif
u16 pageSize; /* Total number of bytes on a page */
u16 usableSize; /* Number of usable bytes on each page */
int maxLocal; /* Maximum local payload in non-LEAFDATA tables */
int minLocal; /* Minimum local payload in non-LEAFDATA tables */
int maxLeaf; /* Maximum local payload in a LEAFDATA table */
int minLeaf; /* Minimum local payload in a LEAFDATA table */
u8 inTransaction; /* Transaction state */
int nTransaction; /* Number of open transactions (read + write) */
void *pSchema; /* Pointer to space allocated by sqlite3BtreeSchema() */
void (*xFreeSchema)(void*); /* Destructor for BtShared.pSchema */
sqlite3_mutex *mutex; /* Non-recursive mutex required to access this struct */
BusyHandler busyHdr; /* The busy handler for this btree */
#ifndef SQLITE_OMIT_SHARED_CACHE
int nRef; /* Number of references to this structure */
BtShared *pNext; /* Next on a list of sharable BtShared structs */
BtLock *pLock; /* List of locks held on this shared-btree struct */
Btree *pExclusive; /* Btree with an EXCLUSIVE lock on the whole db */
#endif
u8 *pTmpSpace; /* BtShared.pageSize bytes of space for tmp use */
};
/*
** An instance of the following structure is used to hold information
** about a cell. The parseCellPtr() function fills in this structure
** based on information extract from the raw disk page.
*/
typedef struct CellInfo CellInfo;
struct CellInfo {
u8 *pCell; /* Pointer to the start of cell content */
i64 nKey; /* The key for INTKEY tables, or number of bytes in key */
u32 nData; /* Number of bytes of data */
u32 nPayload; /* Total amount of payload */
u16 nHeader; /* Size of the cell content header in bytes */
u16 nLocal; /* Amount of payload held locally */
u16 iOverflow; /* Offset to overflow page number. Zero if no overflow */
u16 nSize; /* Size of the cell content on the main b-tree page */
};
/*
** A cursor is a pointer to a particular entry within a particular
** b-tree within a database file.
**
** The entry is identified by its MemPage and the index in
** MemPage.aCell[] of the entry.
**
** When a single database file can shared by two more database connections,
** but cursors cannot be shared. Each cursor is associated with a
** particular database connection identified BtCursor.pBtree.db.
**
** Fields in this structure are accessed under the BtShared.mutex
** found at self->pBt->mutex.
*/
struct BtCursor {
Btree *pBtree; /* The Btree to which this cursor belongs */
BtShared *pBt; /* The BtShared this cursor points to */
BtCursor *pNext, *pPrev; /* Forms a linked list of all cursors */
struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */
Pgno pgnoRoot; /* The root page of this tree */
MemPage *pPage; /* Page that contains the entry */
int idx; /* Index of the entry in pPage->aCell[] */
CellInfo info; /* A parse of the cell we are pointing at */
u8 wrFlag; /* True if writable */
u8 atLast; /* Cursor pointing to the last entry */
u8 validNKey; /* True if info.nKey is valid */
u8 eState; /* One of the CURSOR_XXX constants (see below) */
void *pKey; /* Saved key that was cursor's last known position */
i64 nKey; /* Size of pKey, or last integer key */
int skip; /* (skip<0) -> Prev() is a no-op. (skip>0) -> Next() is */
#ifndef SQLITE_OMIT_INCRBLOB
u8 isIncrblobHandle; /* True if this cursor is an incr. io handle */
Pgno *aOverflow; /* Cache of overflow page locations */
#endif
};
/*
** Potential values for BtCursor.eState.
**
** CURSOR_VALID:
** Cursor points to a valid entry. getPayload() etc. may be called.
**
** CURSOR_INVALID:
** Cursor does not point to a valid entry. This can happen (for example)
** because the table is empty or because BtreeCursorFirst() has not been
** called.
**
** CURSOR_REQUIRESEEK:
** The table that this cursor was opened on still exists, but has been
** modified since the cursor was last used. The cursor position is saved
** in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in
** this state, restoreCursorPosition() can be called to attempt to
** seek the cursor to the saved position.
**
** CURSOR_FAULT:
** A unrecoverable error (an I/O error or a malloc failure) has occurred
** on a different connection that shares the BtShared cache with this
** cursor. The error has left the cache in an inconsistent state.
** Do nothing else with this cursor. Any attempt to use the cursor
** should return the error code stored in BtCursor.skip
*/
#define CURSOR_INVALID 0
#define CURSOR_VALID 1
#define CURSOR_REQUIRESEEK 2
#define CURSOR_FAULT 3
/* The database page the PENDING_BYTE occupies. This page is never used.
** TODO: This macro is very similary to PAGER_MJ_PGNO() in pager.c. They
** should possibly be consolidated (presumably in pager.h).
**
** If disk I/O is omitted (meaning that the database is stored purely
** in memory) then there is no pending byte.
*/
#ifdef SQLITE_OMIT_DISKIO
# define PENDING_BYTE_PAGE(pBt) 0x7fffffff
#else
# define PENDING_BYTE_PAGE(pBt) ((PENDING_BYTE/(pBt)->pageSize)+1)
#endif
/*
** A linked list of the following structures is stored at BtShared.pLock.
** Locks are added (or upgraded from READ_LOCK to WRITE_LOCK) when a cursor
** is opened on the table with root page BtShared.iTable. Locks are removed
** from this list when a transaction is committed or rolled back, or when
** a btree handle is closed.
*/
struct BtLock {
Btree *pBtree; /* Btree handle holding this lock */
Pgno iTable; /* Root page of table */
u8 eLock; /* READ_LOCK or WRITE_LOCK */
BtLock *pNext; /* Next in BtShared.pLock list */
};
/* Candidate values for BtLock.eLock */
#define READ_LOCK 1
#define WRITE_LOCK 2
/*
** These macros define the location of the pointer-map entry for a
** database page. The first argument to each is the number of usable
** bytes on each page of the database (often 1024). The second is the
** page number to look up in the pointer map.
**
** PTRMAP_PAGENO returns the database page number of the pointer-map
** page that stores the required pointer. PTRMAP_PTROFFSET returns
** the offset of the requested map entry.
**
** If the pgno argument passed to PTRMAP_PAGENO is a pointer-map page,
** then pgno is returned. So (pgno==PTRMAP_PAGENO(pgsz, pgno)) can be
** used to test if pgno is a pointer-map page. PTRMAP_ISPAGE implements
** this test.
*/
#define PTRMAP_PAGENO(pBt, pgno) ptrmapPageno(pBt, pgno)
#define PTRMAP_PTROFFSET(pgptrmap, pgno) (5*(pgno-pgptrmap-1))
#define PTRMAP_ISPAGE(pBt, pgno) (PTRMAP_PAGENO((pBt),(pgno))==(pgno))
/*
** The pointer map is a lookup table that identifies the parent page for
** each child page in the database file. The parent page is the page that
** contains a pointer to the child. Every page in the database contains
** 0 or 1 parent pages. (In this context 'database page' refers
** to any page that is not part of the pointer map itself.) Each pointer map
** entry consists of a single byte 'type' and a 4 byte parent page number.
** The PTRMAP_XXX identifiers below are the valid types.
**
** The purpose of the pointer map is to facility moving pages from one
** position in the file to another as part of autovacuum. When a page
** is moved, the pointer in its parent must be updated to point to the
** new location. The pointer map is used to locate the parent page quickly.
**
** PTRMAP_ROOTPAGE: The database page is a root-page. The page-number is not
** used in this case.
**
** PTRMAP_FREEPAGE: The database page is an unused (free) page. The page-number
** is not used in this case.
**
** PTRMAP_OVERFLOW1: The database page is the first page in a list of
** overflow pages. The page number identifies the page that
** contains the cell with a pointer to this overflow page.
**
** PTRMAP_OVERFLOW2: The database page is the second or later page in a list of
** overflow pages. The page-number identifies the previous
sqlite-amalgamation.c view on Meta::CPAN
}
/* To avoid deadlock, first release all locks with a larger
** BtShared address. Then acquire our lock. Then reacquire
** the other BtShared locks that we used to hold in ascending
** order.
*/
for(pLater=p->pNext; pLater; pLater=pLater->pNext){
assert( pLater->sharable );
assert( pLater->pNext==0 || pLater->pNext->pBt>pLater->pBt );
assert( !pLater->locked || pLater->wantToLock>0 );
if( pLater->locked ){
sqlite3_mutex_leave(pLater->pBt->mutex);
pLater->locked = 0;
}
}
sqlite3_mutex_enter(p->pBt->mutex);
p->locked = 1;
for(pLater=p->pNext; pLater; pLater=pLater->pNext){
if( pLater->wantToLock ){
sqlite3_mutex_enter(pLater->pBt->mutex);
pLater->locked = 1;
}
}
#endif /* SQLITE_MUTEX_NOOP */
}
/*
** Exit the recursive mutex on a Btree.
*/
SQLITE_PRIVATE void sqlite3BtreeLeave(Btree *p){
if( p->sharable ){
assert( p->wantToLock>0 );
p->wantToLock--;
if( p->wantToLock==0 ){
assert( p->locked );
sqlite3_mutex_leave(p->pBt->mutex);
p->locked = 0;
}
}
}
#ifndef NDEBUG
/*
** Return true if the BtShared mutex is held on the btree.
**
** This routine makes no determination one why or another if the
** database connection mutex is held.
**
** This routine is used only from within assert() statements.
*/
SQLITE_PRIVATE int sqlite3BtreeHoldsMutex(Btree *p){
return (p->sharable==0 ||
(p->locked && p->wantToLock && sqlite3_mutex_held(p->pBt->mutex)));
}
#endif
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Enter and leave a mutex on a Btree given a cursor owned by that
** Btree. These entry points are used by incremental I/O and can be
** omitted if that module is not used.
*/
SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor *pCur){
sqlite3BtreeEnter(pCur->pBtree);
}
SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor *pCur){
sqlite3BtreeLeave(pCur->pBtree);
}
#endif /* SQLITE_OMIT_INCRBLOB */
/*
** Enter the mutex on every Btree associated with a database
** connection. This is needed (for example) prior to parsing
** a statement since we will be comparing table and column names
** against all schemas and we do not want those schemas being
** reset out from under us.
**
** There is a corresponding leave-all procedures.
**
** Enter the mutexes in accending order by BtShared pointer address
** to avoid the possibility of deadlock when two threads with
** two or more btrees in common both try to lock all their btrees
** at the same instant.
*/
SQLITE_PRIVATE void sqlite3BtreeEnterAll(sqlite3 *db){
int i;
Btree *p, *pLater;
assert( sqlite3_mutex_held(db->mutex) );
for(i=0; i<db->nDb; i++){
p = db->aDb[i].pBt;
if( p && p->sharable ){
p->wantToLock++;
if( !p->locked ){
assert( p->wantToLock==1 );
while( p->pPrev ) p = p->pPrev;
while( p->locked && p->pNext ) p = p->pNext;
for(pLater = p->pNext; pLater; pLater=pLater->pNext){
if( pLater->locked ){
sqlite3_mutex_leave(pLater->pBt->mutex);
pLater->locked = 0;
}
}
while( p ){
sqlite3_mutex_enter(p->pBt->mutex);
p->locked++;
p = p->pNext;
}
}
}
}
}
SQLITE_PRIVATE void sqlite3BtreeLeaveAll(sqlite3 *db){
int i;
Btree *p;
assert( sqlite3_mutex_held(db->mutex) );
for(i=0; i<db->nDb; i++){
p = db->aDb[i].pBt;
if( p && p->sharable ){
sqlite-amalgamation.c view on Meta::CPAN
#endif
/*
** Forward declaration
*/
static int checkReadLocks(Btree*, Pgno, BtCursor*, i64);
#ifdef SQLITE_OMIT_SHARED_CACHE
/*
** The functions queryTableLock(), lockTable() and unlockAllTables()
** manipulate entries in the BtShared.pLock linked list used to store
** shared-cache table level locks. If the library is compiled with the
** shared-cache feature disabled, then there is only ever one user
** of each BtShared structure and so this locking is not necessary.
** So define the lock related functions as no-ops.
*/
#define queryTableLock(a,b,c) SQLITE_OK
#define lockTable(a,b,c) SQLITE_OK
#define unlockAllTables(a)
#endif
#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Query to see if btree handle p may obtain a lock of type eLock
** (READ_LOCK or WRITE_LOCK) on the table with root-page iTab. Return
** SQLITE_OK if the lock may be obtained (by calling lockTable()), or
** SQLITE_LOCKED if not.
*/
static int queryTableLock(Btree *p, Pgno iTab, u8 eLock){
BtShared *pBt = p->pBt;
BtLock *pIter;
assert( sqlite3BtreeHoldsMutex(p) );
assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
assert( p->db!=0 );
/* This is a no-op if the shared-cache is not enabled */
if( !p->sharable ){
return SQLITE_OK;
}
/* If some other connection is holding an exclusive lock, the
** requested lock may not be obtained.
*/
if( pBt->pExclusive && pBt->pExclusive!=p ){
return SQLITE_LOCKED;
}
/* This (along with lockTable()) is where the ReadUncommitted flag is
** dealt with. If the caller is querying for a read-lock and the flag is
** set, it is unconditionally granted - even if there are write-locks
** on the table. If a write-lock is requested, the ReadUncommitted flag
** is not considered.
**
** In function lockTable(), if a read-lock is demanded and the
** ReadUncommitted flag is set, no entry is added to the locks list
** (BtShared.pLock).
**
** To summarize: If the ReadUncommitted flag is set, then read cursors do
** not create or respect table locks. The locking procedure for a
** write-cursor does not change.
*/
if(
0==(p->db->flags&SQLITE_ReadUncommitted) ||
eLock==WRITE_LOCK ||
iTab==MASTER_ROOT
){
for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
if( pIter->pBtree!=p && pIter->iTable==iTab &&
(pIter->eLock!=eLock || eLock!=READ_LOCK) ){
return SQLITE_LOCKED;
}
}
}
return SQLITE_OK;
}
#endif /* !SQLITE_OMIT_SHARED_CACHE */
#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Add a lock on the table with root-page iTable to the shared-btree used
** by Btree handle p. Parameter eLock must be either READ_LOCK or
** WRITE_LOCK.
**
** SQLITE_OK is returned if the lock is added successfully. SQLITE_BUSY and
** SQLITE_NOMEM may also be returned.
*/
static int lockTable(Btree *p, Pgno iTable, u8 eLock){
BtShared *pBt = p->pBt;
BtLock *pLock = 0;
BtLock *pIter;
assert( sqlite3BtreeHoldsMutex(p) );
assert( eLock==READ_LOCK || eLock==WRITE_LOCK );
assert( p->db!=0 );
/* This is a no-op if the shared-cache is not enabled */
if( !p->sharable ){
return SQLITE_OK;
}
assert( SQLITE_OK==queryTableLock(p, iTable, eLock) );
/* If the read-uncommitted flag is set and a read-lock is requested,
** return early without adding an entry to the BtShared.pLock list. See
** comment in function queryTableLock() for more info on handling
** the ReadUncommitted flag.
*/
if(
(p->db->flags&SQLITE_ReadUncommitted) &&
(eLock==READ_LOCK) &&
iTable!=MASTER_ROOT
){
return SQLITE_OK;
}
/* First search the list for an existing lock on this table. */
for(pIter=pBt->pLock; pIter; pIter=pIter->pNext){
if( pIter->iTable==iTable && pIter->pBtree==p ){
pLock = pIter;
break;
sqlite-amalgamation.c view on Meta::CPAN
/* If the above search did not find a BtLock struct associating Btree p
** with table iTable, allocate one and link it into the list.
*/
if( !pLock ){
pLock = (BtLock *)sqlite3MallocZero(sizeof(BtLock));
if( !pLock ){
return SQLITE_NOMEM;
}
pLock->iTable = iTable;
pLock->pBtree = p;
pLock->pNext = pBt->pLock;
pBt->pLock = pLock;
}
/* Set the BtLock.eLock variable to the maximum of the current lock
** and the requested lock. This means if a write-lock was already held
** and a read-lock requested, we don't incorrectly downgrade the lock.
*/
assert( WRITE_LOCK>READ_LOCK );
if( eLock>pLock->eLock ){
pLock->eLock = eLock;
}
return SQLITE_OK;
}
#endif /* !SQLITE_OMIT_SHARED_CACHE */
#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Release all the table locks (locks obtained via calls to the lockTable()
** procedure) held by Btree handle p.
*/
static void unlockAllTables(Btree *p){
BtShared *pBt = p->pBt;
BtLock **ppIter = &pBt->pLock;
assert( sqlite3BtreeHoldsMutex(p) );
assert( p->sharable || 0==*ppIter );
while( *ppIter ){
BtLock *pLock = *ppIter;
assert( pBt->pExclusive==0 || pBt->pExclusive==pLock->pBtree );
if( pLock->pBtree==p ){
*ppIter = pLock->pNext;
sqlite3_free(pLock);
}else{
ppIter = &pLock->pNext;
}
}
if( pBt->pExclusive==p ){
pBt->pExclusive = 0;
}
}
#endif /* SQLITE_OMIT_SHARED_CACHE */
static void releasePage(MemPage *pPage); /* Forward reference */
/*
** Verify that the cursor holds a mutex on the BtShared
*/
#ifndef NDEBUG
static int cursorHoldsMutex(BtCursor *p){
return sqlite3_mutex_held(p->pBt->mutex);
}
#endif
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Invalidate the overflow page-list cache for cursor pCur, if any.
*/
static void invalidateOverflowCache(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
sqlite3_free(pCur->aOverflow);
pCur->aOverflow = 0;
}
/*
** Invalidate the overflow page-list cache for all cursors opened
** on the shared btree structure pBt.
*/
static void invalidateAllOverflowCache(BtShared *pBt){
BtCursor *p;
assert( sqlite3_mutex_held(pBt->mutex) );
for(p=pBt->pCursor; p; p=p->pNext){
invalidateOverflowCache(p);
}
}
#else
#define invalidateOverflowCache(x)
#define invalidateAllOverflowCache(x)
#endif
/*
** Save the current cursor position in the variables BtCursor.nKey
** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK.
*/
static int saveCursorPosition(BtCursor *pCur){
int rc;
assert( CURSOR_VALID==pCur->eState );
assert( 0==pCur->pKey );
assert( cursorHoldsMutex(pCur) );
rc = sqlite3BtreeKeySize(pCur, &pCur->nKey);
/* If this is an intKey table, then the above call to BtreeKeySize()
** stores the integer key in pCur->nKey. In this case this value is
** all that is required. Otherwise, if pCur is not open on an intKey
** table, then malloc space for and store the pCur->nKey bytes of key
** data.
*/
if( rc==SQLITE_OK && 0==pCur->pPage->intKey){
void *pKey = sqlite3Malloc(pCur->nKey);
if( pKey ){
rc = sqlite3BtreeKey(pCur, 0, pCur->nKey, pKey);
if( rc==SQLITE_OK ){
pCur->pKey = pKey;
}else{
sqlite3_free(pKey);
}
}else{
rc = SQLITE_NOMEM;
}
}
assert( !pCur->pPage->intKey || !pCur->pKey );
if( rc==SQLITE_OK ){
releasePage(pCur->pPage);
pCur->pPage = 0;
pCur->eState = CURSOR_REQUIRESEEK;
}
invalidateOverflowCache(pCur);
return rc;
}
/*
** Save the positions of all cursors except pExcept open on the table
** with root-page iRoot. Usually, this is called just before cursor
** pExcept is used to modify the table (BtreeDelete() or BtreeInsert()).
*/
static int saveAllCursors(BtShared *pBt, Pgno iRoot, BtCursor *pExcept){
BtCursor *p;
assert( sqlite3_mutex_held(pBt->mutex) );
assert( pExcept==0 || pExcept->pBt==pBt );
for(p=pBt->pCursor; p; p=p->pNext){
if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) &&
p->eState==CURSOR_VALID ){
int rc = saveCursorPosition(p);
if( SQLITE_OK!=rc ){
return rc;
}
}
}
return SQLITE_OK;
}
/*
** Clear the current cursor position.
*/
static void clearCursorPosition(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
sqlite3_free(pCur->pKey);
pCur->pKey = 0;
pCur->eState = CURSOR_INVALID;
}
/*
** Restore the cursor to the position it was in (or as close to as possible)
** when saveCursorPosition() was called. Note that this call deletes the
** saved position info stored by saveCursorPosition(), so there can be
** at most one effective restoreCursorPosition() call after each
** saveCursorPosition().
*/
SQLITE_PRIVATE int sqlite3BtreeRestoreCursorPosition(BtCursor *pCur){
int rc;
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState>=CURSOR_REQUIRESEEK );
if( pCur->eState==CURSOR_FAULT ){
return pCur->skip;
}
pCur->eState = CURSOR_INVALID;
rc = sqlite3BtreeMoveto(pCur, pCur->pKey, 0, pCur->nKey, 0, &pCur->skip);
if( rc==SQLITE_OK ){
sqlite3_free(pCur->pKey);
pCur->pKey = 0;
assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
}
return rc;
}
#define restoreCursorPosition(p) \
(p->eState>=CURSOR_REQUIRESEEK ? \
sqlite3BtreeRestoreCursorPosition(p) : \
SQLITE_OK)
/*
** Determine whether or not a cursor has moved from the position it
** was last placed at. Cursor can move when the row they are pointing
** at is deleted out from under them.
**
** This routine returns an error code if something goes wrong. The
** integer *pHasMoved is set to one if the cursor has moved and 0 if not.
*/
SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor *pCur, int *pHasMoved){
int rc;
rc = restoreCursorPosition(pCur);
if( rc ){
*pHasMoved = 1;
return rc;
}
if( pCur->eState!=CURSOR_VALID || pCur->skip!=0 ){
*pHasMoved = 1;
}else{
*pHasMoved = 0;
}
return SQLITE_OK;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Given a page number of a regular database page, return the page
** number for the pointer-map page that contains the entry for the
** input page number.
*/
static Pgno ptrmapPageno(BtShared *pBt, Pgno pgno){
int nPagesPerMapPage, iPtrMap, ret;
assert( sqlite3_mutex_held(pBt->mutex) );
nPagesPerMapPage = (pBt->usableSize/5)+1;
iPtrMap = (pgno-2)/nPagesPerMapPage;
ret = (iPtrMap*nPagesPerMapPage) + 2;
if( ret==PENDING_BYTE_PAGE(pBt) ){
ret++;
}
return ret;
}
/*
** Write an entry into the pointer map.
**
** This routine updates the pointer map entry for page number 'key'
** so that it maps to type 'eType' and parent page number 'pgno'.
** An error code is returned if something goes wrong, otherwise SQLITE_OK.
*/
static int ptrmapPut(BtShared *pBt, Pgno key, u8 eType, Pgno parent){
DbPage *pDbPage; /* The pointer map page */
u8 *pPtrmap; /* The pointer map data */
Pgno iPtrmap; /* The pointer map page number */
int offset; /* Offset in pointer map page */
int rc;
assert( sqlite3_mutex_held(pBt->mutex) );
/* The master-journal page number must never be used as a pointer map page */
assert( 0==PTRMAP_ISPAGE(pBt, PENDING_BYTE_PAGE(pBt)) );
assert( pBt->autoVacuum );
if( key==0 ){
return SQLITE_CORRUPT_BKPT;
}
iPtrmap = PTRMAP_PAGENO(pBt, key);
rc = sqlite3PagerGet(pBt->pPager, iPtrmap, &pDbPage);
if( rc!=SQLITE_OK ){
sqlite-amalgamation.c view on Meta::CPAN
/*
** Decrement the BtShared.nRef counter. When it reaches zero,
** remove the BtShared structure from the sharing list. Return
** true if the BtShared.nRef counter reaches zero and return
** false if it is still positive.
*/
static int removeFromSharingList(BtShared *pBt){
#ifndef SQLITE_OMIT_SHARED_CACHE
sqlite3_mutex *pMaster;
BtShared *pList;
int removed = 0;
assert( sqlite3_mutex_notheld(pBt->mutex) );
pMaster = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
sqlite3_mutex_enter(pMaster);
pBt->nRef--;
if( pBt->nRef<=0 ){
if( sqlite3SharedCacheList==pBt ){
sqlite3SharedCacheList = pBt->pNext;
}else{
pList = sqlite3SharedCacheList;
while( ALWAYS(pList) && pList->pNext!=pBt ){
pList=pList->pNext;
}
if( ALWAYS(pList) ){
pList->pNext = pBt->pNext;
}
}
if( SQLITE_THREADSAFE ){
sqlite3_mutex_free(pBt->mutex);
}
removed = 1;
}
sqlite3_mutex_leave(pMaster);
return removed;
#else
return 1;
#endif
}
/*
** Make sure pBt->pTmpSpace points to an allocation of
** MX_CELL_SIZE(pBt) bytes.
*/
static void allocateTempSpace(BtShared *pBt){
if( !pBt->pTmpSpace ){
pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );
}
}
/*
** Free the pBt->pTmpSpace allocation
*/
static void freeTempSpace(BtShared *pBt){
sqlite3PageFree( pBt->pTmpSpace);
pBt->pTmpSpace = 0;
}
/*
** Close an open database and invalidate all cursors.
*/
SQLITE_PRIVATE int sqlite3BtreeClose(Btree *p){
BtShared *pBt = p->pBt;
BtCursor *pCur;
/* Close all cursors opened via this handle. */
assert( sqlite3_mutex_held(p->db->mutex) );
sqlite3BtreeEnter(p);
pBt->db = p->db;
pCur = pBt->pCursor;
while( pCur ){
BtCursor *pTmp = pCur;
pCur = pCur->pNext;
if( pTmp->pBtree==p ){
sqlite3BtreeCloseCursor(pTmp);
}
}
/* Rollback any active transaction and free the handle structure.
** The call to sqlite3BtreeRollback() drops any table-locks held by
** this handle.
*/
sqlite3BtreeRollback(p);
sqlite3BtreeLeave(p);
/* If there are still other outstanding references to the shared-btree
** structure, return now. The remainder of this procedure cleans
** up the shared-btree.
*/
assert( p->wantToLock==0 && p->locked==0 );
if( !p->sharable || removeFromSharingList(pBt) ){
/* The pBt is no longer on the sharing list, so we can access
** it without having to hold the mutex.
**
** Clean out and delete the BtShared object.
*/
assert( !pBt->pCursor );
sqlite3PagerClose(pBt->pPager);
if( pBt->xFreeSchema && pBt->pSchema ){
pBt->xFreeSchema(pBt->pSchema);
}
sqlite3_free(pBt->pSchema);
freeTempSpace(pBt);
sqlite3_free(pBt);
}
#ifndef SQLITE_OMIT_SHARED_CACHE
assert( p->wantToLock==0 );
assert( p->locked==0 );
if( p->pPrev ) p->pPrev->pNext = p->pNext;
if( p->pNext ) p->pNext->pPrev = p->pPrev;
#endif
sqlite3_free(p);
return SQLITE_OK;
}
/*
** Change the limit on the number of pages allowed in the cache.
**
** The maximum number of cache pages is set to the absolute
** value of mxPage. If mxPage is negative, the pager will
** operate asynchronously - it will not stop to do fsync()s
** to insure data is written to the disk surface before
** continuing. Transactions still work if synchronous is off,
** and the database cannot be corrupted if this program
sqlite-amalgamation.c view on Meta::CPAN
}
pBt->pageSize = pageSize;
pBt->usableSize = usableSize;
#ifndef SQLITE_OMIT_AUTOVACUUM
pBt->autoVacuum = (get4byte(&page1[36 + 4*4])?1:0);
pBt->incrVacuum = (get4byte(&page1[36 + 7*4])?1:0);
#endif
}
/* maxLocal is the maximum amount of payload to store locally for
** a cell. Make sure it is small enough so that at least minFanout
** cells can will fit on one page. We assume a 10-byte page header.
** Besides the payload, the cell must store:
** 2-byte pointer to the cell
** 4-byte child pointer
** 9-byte nKey value
** 4-byte nData value
** 4-byte overflow page pointer
** So a cell consists of a 2-byte poiner, a header which is as much as
** 17 bytes long, 0 to N bytes of payload, and an optional 4 byte overflow
** page pointer.
*/
pBt->maxLocal = (pBt->usableSize-12)*64/255 - 23;
pBt->minLocal = (pBt->usableSize-12)*32/255 - 23;
pBt->maxLeaf = pBt->usableSize - 35;
pBt->minLeaf = (pBt->usableSize-12)*32/255 - 23;
assert( pBt->maxLeaf + 23 <= MX_CELL_SIZE(pBt) );
pBt->pPage1 = pPage1;
return SQLITE_OK;
page1_init_failed:
releasePage(pPage1);
pBt->pPage1 = 0;
return rc;
}
/*
** This routine works like lockBtree() except that it also invokes the
** busy callback if there is lock contention.
*/
static int lockBtreeWithRetry(Btree *pRef){
int rc = SQLITE_OK;
assert( sqlite3BtreeHoldsMutex(pRef) );
if( pRef->inTrans==TRANS_NONE ){
u8 inTransaction = pRef->pBt->inTransaction;
btreeIntegrity(pRef);
rc = sqlite3BtreeBeginTrans(pRef, 0);
pRef->pBt->inTransaction = inTransaction;
pRef->inTrans = TRANS_NONE;
if( rc==SQLITE_OK ){
pRef->pBt->nTransaction--;
}
btreeIntegrity(pRef);
}
return rc;
}
/*
** If there are no outstanding cursors and we are not in the middle
** of a transaction but there is a read lock on the database, then
** this routine unrefs the first page of the database file which
** has the effect of releasing the read lock.
**
** If there are any outstanding cursors, this routine is a no-op.
**
** If there is a transaction in progress, this routine is a no-op.
*/
static void unlockBtreeIfUnused(BtShared *pBt){
assert( sqlite3_mutex_held(pBt->mutex) );
if( pBt->inTransaction==TRANS_NONE && pBt->pCursor==0 && pBt->pPage1!=0 ){
if( sqlite3PagerRefcount(pBt->pPager)>=1 ){
assert( pBt->pPage1->aData );
#if 0
if( pBt->pPage1->aData==0 ){
MemPage *pPage = pBt->pPage1;
pPage->aData = sqlite3PagerGetData(pPage->pDbPage);
pPage->pBt = pBt;
pPage->pgno = 1;
}
#endif
releasePage(pBt->pPage1);
}
pBt->pPage1 = 0;
pBt->inStmt = 0;
}
}
/*
** Create a new database by initializing the first page of the
** file.
*/
static int newDatabase(BtShared *pBt){
MemPage *pP1;
unsigned char *data;
int rc;
int nPage;
assert( sqlite3_mutex_held(pBt->mutex) );
rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
if( rc!=SQLITE_OK || nPage>0 ){
return rc;
}
pP1 = pBt->pPage1;
assert( pP1!=0 );
data = pP1->aData;
rc = sqlite3PagerWrite(pP1->pDbPage);
if( rc ) return rc;
memcpy(data, zMagicHeader, sizeof(zMagicHeader));
assert( sizeof(zMagicHeader)==16 );
put2byte(&data[16], pBt->pageSize);
data[18] = 1;
data[19] = 1;
data[20] = pBt->pageSize - pBt->usableSize;
data[21] = 64;
data[22] = 32;
data[23] = 32;
memset(&data[24], 0, 100-24);
zeroPage(pP1, PTF_INTKEY|PTF_LEAF|PTF_LEAFDATA );
pBt->pageSizeFixed = 1;
#ifndef SQLITE_OMIT_AUTOVACUUM
assert( pBt->autoVacuum==1 || pBt->autoVacuum==0 );
assert( pBt->incrVacuum==1 || pBt->incrVacuum==0 );
put4byte(&data[36 + 4*4], pBt->autoVacuum);
put4byte(&data[36 + 7*4], pBt->incrVacuum);
sqlite-amalgamation.c view on Meta::CPAN
/*
** This routine does the first phase of a two-phase commit. This routine
** causes a rollback journal to be created (if it does not already exist)
** and populated with enough information so that if a power loss occurs
** the database can be restored to its original state by playing back
** the journal. Then the contents of the journal are flushed out to
** the disk. After the journal is safely on oxide, the changes to the
** database are written into the database file and flushed to oxide.
** At the end of this call, the rollback journal still exists on the
** disk and we are still holding all locks, so the transaction has not
** committed. See sqlite3BtreeCommit() for the second phase of the
** commit process.
**
** This call is a no-op if no write-transaction is currently active on pBt.
**
** Otherwise, sync the database file for the btree pBt. zMaster points to
** the name of a master journal file that should be written into the
** individual journal file, or is NULL, indicating no master journal file
** (single database transaction).
**
** When this is called, the master journal should already have been
** created, populated with this journal pointer and synced to disk.
**
** Once this is routine has returned, the only thing required to commit
** the write-transaction for this database file is to delete the journal.
*/
SQLITE_PRIVATE int sqlite3BtreeCommitPhaseOne(Btree *p, const char *zMaster){
int rc = SQLITE_OK;
if( p->inTrans==TRANS_WRITE ){
BtShared *pBt = p->pBt;
Pgno nTrunc = 0;
sqlite3BtreeEnter(p);
pBt->db = p->db;
#ifndef SQLITE_OMIT_AUTOVACUUM
if( pBt->autoVacuum ){
rc = autoVacuumCommit(pBt, &nTrunc);
if( rc!=SQLITE_OK ){
sqlite3BtreeLeave(p);
return rc;
}
}
#endif
rc = sqlite3PagerCommitPhaseOne(pBt->pPager, zMaster, nTrunc, 0);
sqlite3BtreeLeave(p);
}
return rc;
}
/*
** Commit the transaction currently in progress.
**
** This routine implements the second phase of a 2-phase commit. The
** sqlite3BtreeSync() routine does the first phase and should be invoked
** prior to calling this routine. The sqlite3BtreeSync() routine did
** all the work of writing information out to disk and flushing the
** contents so that they are written onto the disk platter. All this
** routine has to do is delete or truncate the rollback journal
** (which causes the transaction to commit) and drop locks.
**
** This will release the write lock on the database file. If there
** are no active cursors, it also releases the read lock.
*/
SQLITE_PRIVATE int sqlite3BtreeCommitPhaseTwo(Btree *p){
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
pBt->db = p->db;
btreeIntegrity(p);
/* If the handle has a write-transaction open, commit the shared-btrees
** transaction and set the shared state to TRANS_READ.
*/
if( p->inTrans==TRANS_WRITE ){
int rc;
assert( pBt->inTransaction==TRANS_WRITE );
assert( pBt->nTransaction>0 );
rc = sqlite3PagerCommitPhaseTwo(pBt->pPager);
if( rc!=SQLITE_OK ){
sqlite3BtreeLeave(p);
return rc;
}
pBt->inTransaction = TRANS_READ;
pBt->inStmt = 0;
}
unlockAllTables(p);
/* If the handle has any kind of transaction open, decrement the transaction
** count of the shared btree. If the transaction count reaches 0, set
** the shared state to TRANS_NONE. The unlockBtreeIfUnused() call below
** will unlock the pager.
*/
if( p->inTrans!=TRANS_NONE ){
pBt->nTransaction--;
if( 0==pBt->nTransaction ){
pBt->inTransaction = TRANS_NONE;
}
}
/* Set the handles current transaction state to TRANS_NONE and unlock
** the pager if this call closed the only read or write transaction.
*/
p->inTrans = TRANS_NONE;
unlockBtreeIfUnused(pBt);
btreeIntegrity(p);
sqlite3BtreeLeave(p);
return SQLITE_OK;
}
/*
** Do both phases of a commit.
*/
SQLITE_PRIVATE int sqlite3BtreeCommit(Btree *p){
int rc;
sqlite3BtreeEnter(p);
rc = sqlite3BtreeCommitPhaseOne(p, 0);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeCommitPhaseTwo(p);
}
sqlite3BtreeLeave(p);
return rc;
}
#ifndef NDEBUG
/*
** Return the number of write-cursors open on this handle. This is for use
** in assert() expressions, so it is only compiled if NDEBUG is not
** defined.
**
** For the purposes of this routine, a write-cursor is any cursor that
** is capable of writing to the databse. That means the cursor was
** originally opened for writing and the cursor has not be disabled
** by having its state changed to CURSOR_FAULT.
*/
static int countWriteCursors(BtShared *pBt){
BtCursor *pCur;
int r = 0;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
if( pCur->wrFlag && pCur->eState!=CURSOR_FAULT ) r++;
}
return r;
}
#endif
/*
** This routine sets the state to CURSOR_FAULT and the error
** code to errCode for every cursor on BtShared that pBtree
** references.
**
** Every cursor is tripped, including cursors that belong
** to other database connections that happen to be sharing
** the cache with pBtree.
**
** This routine gets called when a rollback occurs.
** All cursors using the same cache must be tripped
** to prevent them from trying to use the btree after
** the rollback. The rollback may have deleted tables
** or moved root pages, so it is not sufficient to
** save the state of the cursor. The cursor must be
** invalidated.
*/
SQLITE_PRIVATE void sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode){
BtCursor *p;
sqlite3BtreeEnter(pBtree);
for(p=pBtree->pBt->pCursor; p; p=p->pNext){
clearCursorPosition(p);
p->eState = CURSOR_FAULT;
p->skip = errCode;
}
sqlite3BtreeLeave(pBtree);
}
/*
** Rollback the transaction in progress. All cursors will be
** invalided by this operation. Any attempt to use a cursor
** that was open at the beginning of this operation will result
** in an error.
**
** This will release the write lock on the database file. If there
** are no active cursors, it also releases the read lock.
*/
SQLITE_PRIVATE int sqlite3BtreeRollback(Btree *p){
int rc;
BtShared *pBt = p->pBt;
MemPage *pPage1;
sqlite3BtreeEnter(p);
pBt->db = p->db;
rc = saveAllCursors(pBt, 0, 0);
#ifndef SQLITE_OMIT_SHARED_CACHE
if( rc!=SQLITE_OK ){
/* This is a horrible situation. An IO or malloc() error occured whilst
** trying to save cursor positions. If this is an automatic rollback (as
** the result of a constraint, malloc() failure or IO error) then
** the cache may be internally inconsistent (not contain valid trees) so
** we cannot simply return the error to the caller. Instead, abort
** all queries that may be using any of the cursors that failed to save.
*/
sqlite3BtreeTripAllCursors(p, rc);
}
#endif
btreeIntegrity(p);
unlockAllTables(p);
if( p->inTrans==TRANS_WRITE ){
int rc2;
#ifndef SQLITE_OMIT_AUTOVACUUM
pBt->nTrunc = 0;
#endif
assert( TRANS_WRITE==pBt->inTransaction );
rc2 = sqlite3PagerRollback(pBt->pPager);
if( rc2!=SQLITE_OK ){
rc = rc2;
}
/* The rollback may have destroyed the pPage1->aData value. So
** call sqlite3BtreeGetPage() on page 1 again to make
** sure pPage1->aData is set correctly. */
if( sqlite3BtreeGetPage(pBt, 1, &pPage1, 0)==SQLITE_OK ){
releasePage(pPage1);
}
assert( countWriteCursors(pBt)==0 );
pBt->inTransaction = TRANS_READ;
}
if( p->inTrans!=TRANS_NONE ){
assert( pBt->nTransaction>0 );
pBt->nTransaction--;
if( 0==pBt->nTransaction ){
pBt->inTransaction = TRANS_NONE;
}
}
p->inTrans = TRANS_NONE;
pBt->inStmt = 0;
unlockBtreeIfUnused(pBt);
btreeIntegrity(p);
sqlite3BtreeLeave(p);
return rc;
}
/*
** Start a statement subtransaction. The subtransaction can
** can be rolled back independently of the main transaction.
** You must start a transaction before starting a subtransaction.
** The subtransaction is ended automatically if the main transaction
** commits or rolls back.
**
** Only one subtransaction may be active at a time. It is an error to try
** to start a new subtransaction if another subtransaction is already active.
**
** Statement subtransactions are used around individual SQL statements
** that are contained within a BEGIN...COMMIT block. If a constraint
** error occurs within the statement, the effect of that one statement
** can be rolled back without having to rollback the entire transaction.
*/
SQLITE_PRIVATE int sqlite3BtreeBeginStmt(Btree *p){
int rc;
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
pBt->db = p->db;
if( (p->inTrans!=TRANS_WRITE) || pBt->inStmt ){
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}else{
assert( pBt->inTransaction==TRANS_WRITE );
rc = pBt->readOnly ? SQLITE_OK : sqlite3PagerStmtBegin(pBt->pPager);
pBt->inStmt = 1;
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** Commit the statment subtransaction currently in progress. If no
** subtransaction is active, this is a no-op.
*/
SQLITE_PRIVATE int sqlite3BtreeCommitStmt(Btree *p){
int rc;
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
pBt->db = p->db;
if( pBt->inStmt && !pBt->readOnly ){
rc = sqlite3PagerStmtCommit(pBt->pPager);
}else{
rc = SQLITE_OK;
}
pBt->inStmt = 0;
sqlite3BtreeLeave(p);
return rc;
}
/*
** Rollback the active statement subtransaction. If no subtransaction
** is active this routine is a no-op.
**
** All cursors will be invalidated by this operation. Any attempt
** to use a cursor that was open at the beginning of this operation
** will result in an error.
*/
SQLITE_PRIVATE int sqlite3BtreeRollbackStmt(Btree *p){
int rc = SQLITE_OK;
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
pBt->db = p->db;
if( pBt->inStmt && !pBt->readOnly ){
rc = sqlite3PagerStmtRollback(pBt->pPager);
pBt->inStmt = 0;
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** Create a new cursor for the BTree whose root is on the page
** iTable. The act of acquiring a cursor gets a read lock on
** the database file.
**
** If wrFlag==0, then the cursor can only be used for reading.
** If wrFlag==1, then the cursor can be used for reading or for
** writing if other conditions for writing are also met. These
** are the conditions that must be met in order for writing to
** be allowed:
**
** 1: The cursor must have been opened with wrFlag==1
**
** 2: Other database connections that share the same pager cache
** but which are not in the READ_UNCOMMITTED state may not have
** cursors open with wrFlag==0 on the same table. Otherwise
** the changes made by this write cursor would be visible to
** the read cursors in the other database connection.
**
** 3: The database must be writable (not on read-only media)
**
** 4: There must be an active transaction.
**
** No checking is done to make sure that page iTable really is the
** root page of a b-tree. If it is not, then the cursor acquired
** will not work correctly.
*/
static int btreeCursor(
Btree *p, /* The btree */
int iTable, /* Root page of table to open */
int wrFlag, /* 1 to write. 0 read-only */
struct KeyInfo *pKeyInfo, /* First arg to comparison function */
BtCursor *pCur /* Space for new cursor */
){
int rc;
BtShared *pBt = p->pBt;
assert( sqlite3BtreeHoldsMutex(p) );
if( wrFlag ){
if( pBt->readOnly ){
return SQLITE_READONLY;
}
if( checkReadLocks(p, iTable, 0, 0) ){
return SQLITE_LOCKED;
}
}
if( pBt->pPage1==0 ){
rc = lockBtreeWithRetry(p);
if( rc!=SQLITE_OK ){
return rc;
}
if( pBt->readOnly && wrFlag ){
return SQLITE_READONLY;
}
}
pCur->pgnoRoot = (Pgno)iTable;
if( iTable==1 && pagerPagecount(pBt->pPager)==0 ){
rc = SQLITE_EMPTY;
goto create_cursor_exception;
}
rc = getAndInitPage(pBt, pCur->pgnoRoot, &pCur->pPage, 0);
if( rc!=SQLITE_OK ){
goto create_cursor_exception;
}
/* Now that no other errors can occur, finish filling in the BtCursor
** variables, link the cursor into the BtShared list and set *ppCur (the
** output argument to this function).
*/
pCur->pKeyInfo = pKeyInfo;
pCur->pBtree = p;
pCur->pBt = pBt;
pCur->wrFlag = wrFlag;
pCur->pNext = pBt->pCursor;
if( pCur->pNext ){
pCur->pNext->pPrev = pCur;
}
pBt->pCursor = pCur;
pCur->eState = CURSOR_INVALID;
return SQLITE_OK;
create_cursor_exception:
releasePage(pCur->pPage);
unlockBtreeIfUnused(pBt);
return rc;
}
SQLITE_PRIVATE int sqlite3BtreeCursor(
Btree *p, /* The btree */
int iTable, /* Root page of table to open */
int wrFlag, /* 1 to write. 0 read-only */
struct KeyInfo *pKeyInfo, /* First arg to xCompare() */
BtCursor *pCur /* Write new cursor here */
){
int rc;
sqlite3BtreeEnter(p);
p->pBt->db = p->db;
rc = btreeCursor(p, iTable, wrFlag, pKeyInfo, pCur);
sqlite3BtreeLeave(p);
return rc;
}
SQLITE_PRIVATE int sqlite3BtreeCursorSize(){
return sizeof(BtCursor);
}
/*
** Close a cursor. The read lock on the database file is released
** when the last cursor is closed.
*/
SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor *pCur){
Btree *pBtree = pCur->pBtree;
if( pBtree ){
BtShared *pBt = pCur->pBt;
sqlite3BtreeEnter(pBtree);
pBt->db = pBtree->db;
clearCursorPosition(pCur);
if( pCur->pPrev ){
pCur->pPrev->pNext = pCur->pNext;
}else{
pBt->pCursor = pCur->pNext;
}
if( pCur->pNext ){
pCur->pNext->pPrev = pCur->pPrev;
}
releasePage(pCur->pPage);
unlockBtreeIfUnused(pBt);
invalidateOverflowCache(pCur);
/* sqlite3_free(pCur); */
sqlite3BtreeLeave(pBtree);
}
return SQLITE_OK;
}
/*
** Make a temporary cursor by filling in the fields of pTempCur.
** The temporary cursor is not on the cursor list for the Btree.
*/
SQLITE_PRIVATE void sqlite3BtreeGetTempCursor(BtCursor *pCur, BtCursor *pTempCur){
assert( cursorHoldsMutex(pCur) );
memcpy(pTempCur, pCur, sizeof(*pCur));
pTempCur->pNext = 0;
pTempCur->pPrev = 0;
if( pTempCur->pPage ){
sqlite3PagerRef(pTempCur->pPage->pDbPage);
}
}
/*
** Delete a temporary cursor such as was made by the CreateTemporaryCursor()
** function above.
*/
SQLITE_PRIVATE void sqlite3BtreeReleaseTempCursor(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
if( pCur->pPage ){
sqlite3PagerUnref(pCur->pPage->pDbPage);
}
}
/*
** Make sure the BtCursor* given in the argument has a valid
** BtCursor.info structure. If it is not already valid, call
** sqlite3BtreeParseCell() to fill it in.
**
** BtCursor.info is a cache of the information in the current cell.
** Using this cache reduces the number of calls to sqlite3BtreeParseCell().
**
** 2007-06-25: There is a bug in some versions of MSVC that cause the
** compiler to crash when getCellInfo() is implemented as a macro.
** But there is a measureable speed advantage to using the macro on gcc
** (when less compiler optimizations like -Os or -O0 are used and the
** compiler is not doing agressive inlining.) So we use a real function
** for MSVC and a macro for everything else. Ticket #2457.
*/
#ifndef NDEBUG
static void assertCellInfo(BtCursor *pCur){
CellInfo info;
memset(&info, 0, sizeof(info));
sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &info);
assert( memcmp(&info, &pCur->info, sizeof(info))==0 );
}
#else
#define assertCellInfo(x)
#endif
#ifdef _MSC_VER
/* Use a real function in MSVC to work around bugs in that compiler. */
static void getCellInfo(BtCursor *pCur){
if( pCur->info.nSize==0 ){
sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &pCur->info);
pCur->validNKey = 1;
}else{
assertCellInfo(pCur);
}
}
#else /* if not _MSC_VER */
/* Use a macro in all other compilers so that the function is inlined */
#define getCellInfo(pCur) \
if( pCur->info.nSize==0 ){ \
sqlite3BtreeParseCell(pCur->pPage, pCur->idx, &pCur->info); \
pCur->validNKey = 1; \
}else{ \
assertCellInfo(pCur); \
}
#endif /* _MSC_VER */
/*
** Set *pSize to the size of the buffer needed to hold the value of
** the key for the current entry. If the cursor is not pointing
** to a valid entry, *pSize is set to 0.
**
** For a table with the INTKEY flag set, this routine returns the key
** itself, not the number of bytes in the key.
*/
SQLITE_PRIVATE int sqlite3BtreeKeySize(BtCursor *pCur, i64 *pSize){
int rc;
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
if( pCur->eState==CURSOR_INVALID ){
*pSize = 0;
}else{
getCellInfo(pCur);
*pSize = pCur->info.nKey;
}
}
return rc;
}
/*
** Set *pSize to the number of bytes of data in the entry the
** cursor currently points to. Always return SQLITE_OK.
** Failure is not possible. If the cursor is not currently
** pointing to an entry (which can happen, for example, if
** the database is empty) then *pSize is set to 0.
*/
SQLITE_PRIVATE int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){
int rc;
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_INVALID || pCur->eState==CURSOR_VALID );
if( pCur->eState==CURSOR_INVALID ){
/* Not pointing at a valid entry - set *pSize to 0. */
*pSize = 0;
}else{
getCellInfo(pCur);
*pSize = pCur->info.nData;
}
}
return rc;
}
/*
** Given the page number of an overflow page in the database (parameter
** ovfl), this function finds the page number of the next page in the
** linked list of overflow pages. If possible, it uses the auto-vacuum
** pointer-map data instead of reading the content of page ovfl to do so.
**
** If an error occurs an SQLite error code is returned. Otherwise:
**
** Unless pPgnoNext is NULL, the page number of the next overflow
** page in the linked list is written to *pPgnoNext. If page ovfl
** is the last page in its linked list, *pPgnoNext is set to zero.
**
** If ppPage is not NULL, *ppPage is set to the MemPage* handle
** for page ovfl. The underlying pager page may have been requested
** with the noContent flag set, so the page data accessable via
** this handle may not be trusted.
*/
static int getOverflowPage(
BtShared *pBt,
Pgno ovfl, /* Overflow page */
MemPage **ppPage, /* OUT: MemPage handle */
Pgno *pPgnoNext /* OUT: Next overflow page number */
){
Pgno next = 0;
int rc;
assert( sqlite3_mutex_held(pBt->mutex) );
/* One of these must not be NULL. Otherwise, why call this function? */
assert(ppPage || pPgnoNext);
/* If pPgnoNext is NULL, then this function is being called to obtain
** a MemPage* reference only. No page-data is required in this case.
*/
if( !pPgnoNext ){
return sqlite3BtreeGetPage(pBt, ovfl, ppPage, 1);
}
#ifndef SQLITE_OMIT_AUTOVACUUM
/* Try to find the next page in the overflow list using the
** autovacuum pointer-map pages. Guess that the next page in
** the overflow list is page number (ovfl+1). If that guess turns
** out to be wrong, fall back to loading the data of page
** number ovfl to determine the next page number.
*/
if( pBt->autoVacuum ){
Pgno pgno;
sqlite-amalgamation.c view on Meta::CPAN
next = iGuess;
}
}
}
#endif
if( next==0 || ppPage ){
MemPage *pPage = 0;
rc = sqlite3BtreeGetPage(pBt, ovfl, &pPage, next!=0);
assert(rc==SQLITE_OK || pPage==0);
if( next==0 && rc==SQLITE_OK ){
next = get4byte(pPage->aData);
}
if( ppPage ){
*ppPage = pPage;
}else{
releasePage(pPage);
}
}
*pPgnoNext = next;
return rc;
}
/*
** Copy data from a buffer to a page, or from a page to a buffer.
**
** pPayload is a pointer to data stored on database page pDbPage.
** If argument eOp is false, then nByte bytes of data are copied
** from pPayload to the buffer pointed at by pBuf. If eOp is true,
** then sqlite3PagerWrite() is called on pDbPage and nByte bytes
** of data are copied from the buffer pBuf to pPayload.
**
** SQLITE_OK is returned on success, otherwise an error code.
*/
static int copyPayload(
void *pPayload, /* Pointer to page data */
void *pBuf, /* Pointer to buffer */
int nByte, /* Number of bytes to copy */
int eOp, /* 0 -> copy from page, 1 -> copy to page */
DbPage *pDbPage /* Page containing pPayload */
){
if( eOp ){
/* Copy data from buffer to page (a write operation) */
int rc = sqlite3PagerWrite(pDbPage);
if( rc!=SQLITE_OK ){
return rc;
}
memcpy(pPayload, pBuf, nByte);
}else{
/* Copy data from page to buffer (a read operation) */
memcpy(pBuf, pPayload, nByte);
}
return SQLITE_OK;
}
/*
** This function is used to read or overwrite payload information
** for the entry that the pCur cursor is pointing to. If the eOp
** parameter is 0, this is a read operation (data copied into
** buffer pBuf). If it is non-zero, a write (data copied from
** buffer pBuf).
**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
**
** This routine does not make a distinction between key and data.
** It just reads or writes bytes from the payload area. Data might
** appear on the main page or be scattered out on multiple overflow
** pages.
**
** If the BtCursor.isIncrblobHandle flag is set, and the current
** cursor entry uses one or more overflow pages, this function
** allocates space for and lazily popluates the overflow page-list
** cache array (BtCursor.aOverflow). Subsequent calls use this
** cache to make seeking to the supplied offset more efficient.
**
** Once an overflow page-list cache has been allocated, it may be
** invalidated if some other cursor writes to the same table, or if
** the cursor is moved to a different row. Additionally, in auto-vacuum
** mode, the following events may invalidate an overflow page-list cache.
**
** * An incremental vacuum,
** * A commit in auto_vacuum="full" mode,
** * Creating a table (may require moving an overflow page).
*/
static int accessPayload(
BtCursor *pCur, /* Cursor pointing to entry to read from */
int offset, /* Begin reading this far into payload */
int amt, /* Read this many bytes */
unsigned char *pBuf, /* Write the bytes into this buffer */
int skipKey, /* offset begins at data if this is true */
int eOp /* zero to read. non-zero to write. */
){
unsigned char *aPayload;
int rc = SQLITE_OK;
u32 nKey;
int iIdx = 0;
MemPage *pPage = pCur->pPage; /* Btree page of current cursor entry */
BtShared *pBt; /* Btree this cursor belongs to */
assert( pPage );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
assert( offset>=0 );
assert( cursorHoldsMutex(pCur) );
getCellInfo(pCur);
aPayload = pCur->info.pCell + pCur->info.nHeader;
nKey = (pPage->intKey ? 0 : pCur->info.nKey);
if( skipKey ){
offset += nKey;
}
if( offset+amt > nKey+pCur->info.nData ){
/* Trying to read or write past the end of the data is an error */
return SQLITE_ERROR;
}
/* Check if data must be read/written to/from the btree page itself. */
if( offset<pCur->info.nLocal ){
int a = amt;
if( a+offset>pCur->info.nLocal ){
a = pCur->info.nLocal - offset;
}
rc = copyPayload(&aPayload[offset], pBuf, a, eOp, pPage->pDbPage);
offset = 0;
pBuf += a;
amt -= a;
}else{
offset -= pCur->info.nLocal;
}
pBt = pCur->pBt;
if( rc==SQLITE_OK && amt>0 ){
const int ovflSize = pBt->usableSize - 4; /* Bytes content per ovfl page */
Pgno nextPage;
nextPage = get4byte(&aPayload[pCur->info.nLocal]);
#ifndef SQLITE_OMIT_INCRBLOB
/* If the isIncrblobHandle flag is set and the BtCursor.aOverflow[]
** has not been allocated, allocate it now. The array is sized at
** one entry for each overflow page in the overflow chain. The
** page number of the first overflow page is stored in aOverflow[0],
** etc. A value of 0 in the aOverflow[] array means "not yet known"
** (the cache is lazily populated).
*/
if( pCur->isIncrblobHandle && !pCur->aOverflow ){
int nOvfl = (pCur->info.nPayload-pCur->info.nLocal+ovflSize-1)/ovflSize;
pCur->aOverflow = (Pgno *)sqlite3MallocZero(sizeof(Pgno)*nOvfl);
if( nOvfl && !pCur->aOverflow ){
rc = SQLITE_NOMEM;
}
}
/* If the overflow page-list cache has been allocated and the
** entry for the first required overflow page is valid, skip
** directly to it.
*/
if( pCur->aOverflow && pCur->aOverflow[offset/ovflSize] ){
iIdx = (offset/ovflSize);
nextPage = pCur->aOverflow[iIdx];
offset = (offset%ovflSize);
}
#endif
for( ; rc==SQLITE_OK && amt>0 && nextPage; iIdx++){
#ifndef SQLITE_OMIT_INCRBLOB
/* If required, populate the overflow page-list cache. */
if( pCur->aOverflow ){
assert(!pCur->aOverflow[iIdx] || pCur->aOverflow[iIdx]==nextPage);
pCur->aOverflow[iIdx] = nextPage;
}
#endif
if( offset>=ovflSize ){
/* The only reason to read this page is to obtain the page
** number for the next page in the overflow chain. The page
** data is not required. So first try to lookup the overflow
** page-list cache, if any, then fall back to the getOverflowPage()
** function.
*/
#ifndef SQLITE_OMIT_INCRBLOB
if( pCur->aOverflow && pCur->aOverflow[iIdx+1] ){
nextPage = pCur->aOverflow[iIdx+1];
} else
#endif
rc = getOverflowPage(pBt, nextPage, 0, &nextPage);
offset -= ovflSize;
}else{
/* Need to read this page properly. It contains some of the
** range of data that is being read (eOp==0) or written (eOp!=0).
*/
DbPage *pDbPage;
int a = amt;
rc = sqlite3PagerGet(pBt->pPager, nextPage, &pDbPage);
if( rc==SQLITE_OK ){
aPayload = sqlite3PagerGetData(pDbPage);
nextPage = get4byte(aPayload);
if( a + offset > ovflSize ){
a = ovflSize - offset;
}
rc = copyPayload(&aPayload[offset+4], pBuf, a, eOp, pDbPage);
sqlite3PagerUnref(pDbPage);
offset = 0;
amt -= a;
pBuf += a;
}
}
}
}
if( rc==SQLITE_OK && amt>0 ){
return SQLITE_CORRUPT_BKPT;
}
return rc;
}
/*
** Read part of the key associated with cursor pCur. Exactly
** "amt" bytes will be transfered into pBuf[]. The transfer
** begins at "offset".
**
** Return SQLITE_OK on success or an error code if anything goes
** wrong. An error is returned if "offset+amt" is larger than
** the available payload.
*/
SQLITE_PRIVATE int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
int rc;
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
assert( pCur->pPage!=0 );
if( pCur->pPage->intKey ){
return SQLITE_CORRUPT_BKPT;
}
assert( pCur->pPage->intKey==0 );
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
rc = accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0, 0);
}
return rc;
}
/*
** Read part of the data associated with cursor pCur. Exactly
** "amt" bytes will be transfered into pBuf[]. The transfer
** begins at "offset".
**
** Return SQLITE_OK on success or an error code if anything goes
** wrong. An error is returned if "offset+amt" is larger than
** the available payload.
*/
SQLITE_PRIVATE int sqlite3BtreeData(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
int rc;
#ifndef SQLITE_OMIT_INCRBLOB
if ( pCur->eState==CURSOR_INVALID ){
return SQLITE_ABORT;
}
#endif
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
assert( pCur->pPage!=0 );
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
rc = accessPayload(pCur, offset, amt, pBuf, 1, 0);
}
return rc;
}
/*
** Return a pointer to payload information from the entry that the
** pCur cursor is pointing to. The pointer is to the beginning of
** the key if skipKey==0 and it points to the beginning of data if
** skipKey==1. The number of bytes of available key/data is written
** into *pAmt. If *pAmt==0, then the value returned will not be
** a valid pointer.
**
** This routine is an optimization. It is common for the entire key
** and data to fit on the local page and for there to be no overflow
** pages. When that is so, this routine can be used to access the
** key and data without making a copy. If the key and/or data spills
** onto overflow pages, then accessPayload() must be used to reassembly
** the key/data and copy it into a preallocated buffer.
**
** The pointer returned by this routine looks directly into the cached
** page of the database. The data might change or move the next time
** any btree routine is called.
*/
static const unsigned char *fetchPayload(
BtCursor *pCur, /* Cursor pointing to entry to read from */
int *pAmt, /* Write the number of available bytes here */
int skipKey /* read beginning at data if this is true */
){
unsigned char *aPayload;
MemPage *pPage;
u32 nKey;
int nLocal;
assert( pCur!=0 && pCur->pPage!=0 );
assert( pCur->eState==CURSOR_VALID );
assert( cursorHoldsMutex(pCur) );
pPage = pCur->pPage;
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
getCellInfo(pCur);
aPayload = pCur->info.pCell;
aPayload += pCur->info.nHeader;
if( pPage->intKey ){
nKey = 0;
}else{
nKey = pCur->info.nKey;
}
if( skipKey ){
aPayload += nKey;
nLocal = pCur->info.nLocal - nKey;
}else{
nLocal = pCur->info.nLocal;
if( nLocal>nKey ){
nLocal = nKey;
}
}
*pAmt = nLocal;
return aPayload;
}
/*
** For the entry that cursor pCur is point to, return as
** many bytes of the key or data as are available on the local
** b-tree page. Write the number of available bytes into *pAmt.
**
** The pointer returned is ephemeral. The key/data may move
** or be destroyed on the next call to any Btree routine,
** including calls from other threads against the same cache.
** Hence, a mutex on the BtShared should be held prior to calling
** this routine.
**
** These routines is used to get quick access to key and data
** in the common case where no overflow pages are used.
*/
SQLITE_PRIVATE const void *sqlite3BtreeKeyFetch(BtCursor *pCur, int *pAmt){
assert( cursorHoldsMutex(pCur) );
if( pCur->eState==CURSOR_VALID ){
return (const void*)fetchPayload(pCur, pAmt, 0);
}
return 0;
}
SQLITE_PRIVATE const void *sqlite3BtreeDataFetch(BtCursor *pCur, int *pAmt){
assert( cursorHoldsMutex(pCur) );
if( pCur->eState==CURSOR_VALID ){
return (const void*)fetchPayload(pCur, pAmt, 1);
}
return 0;
}
/*
** Move the cursor down to a new child page. The newPgno argument is the
** page number of the child page to move to.
*/
static int moveToChild(BtCursor *pCur, u32 newPgno){
int rc;
MemPage *pNewPage;
MemPage *pOldPage;
BtShared *pBt = pCur->pBt;
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
rc = getAndInitPage(pBt, newPgno, &pNewPage, pCur->pPage);
if( rc ) return rc;
pNewPage->idxParent = pCur->idx;
pOldPage = pCur->pPage;
pOldPage->idxShift = 0;
releasePage(pOldPage);
pCur->pPage = pNewPage;
pCur->idx = 0;
pCur->info.nSize = 0;
pCur->validNKey = 0;
if( pNewPage->nCell<1 ){
return SQLITE_CORRUPT_BKPT;
}
return SQLITE_OK;
}
/*
** Return true if the page is the virtual root of its table.
**
** The virtual root page is the root page for most tables. But
** for the table rooted on page 1, sometime the real root page
** is empty except for the right-pointer. In such cases the
** virtual root page is the page that the right-pointer of page
** 1 is pointing to.
*/
SQLITE_PRIVATE int sqlite3BtreeIsRootPage(MemPage *pPage){
MemPage *pParent;
assert( sqlite3_mutex_held(pPage->pBt->mutex) );
pParent = pPage->pParent;
if( pParent==0 ) return 1;
if( pParent->pgno>1 ) return 0;
if( get2byte(&pParent->aData[pParent->hdrOffset+3])==0 ) return 1;
return 0;
}
/*
** Move the cursor up to the parent page.
**
** pCur->idx is set to the cell index that contains the pointer
** to the page we are coming from. If we are coming from the
** right-most child page then pCur->idx is set to one more than
** the largest cell index.
*/
SQLITE_PRIVATE void sqlite3BtreeMoveToParent(BtCursor *pCur){
MemPage *pParent;
MemPage *pPage;
int idxParent;
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
pPage = pCur->pPage;
assert( pPage!=0 );
assert( !sqlite3BtreeIsRootPage(pPage) );
pParent = pPage->pParent;
assert( pParent!=0 );
idxParent = pPage->idxParent;
sqlite3PagerRef(pParent->pDbPage);
releasePage(pPage);
pCur->pPage = pParent;
pCur->info.nSize = 0;
pCur->validNKey = 0;
assert( pParent->idxShift==0 );
pCur->idx = idxParent;
}
/*
** Move the cursor to the root page
*/
static int moveToRoot(BtCursor *pCur){
MemPage *pRoot;
int rc = SQLITE_OK;
Btree *p = pCur->pBtree;
BtShared *pBt = p->pBt;
assert( cursorHoldsMutex(pCur) );
assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
assert( CURSOR_VALID < CURSOR_REQUIRESEEK );
assert( CURSOR_FAULT > CURSOR_REQUIRESEEK );
if( pCur->eState>=CURSOR_REQUIRESEEK ){
if( pCur->eState==CURSOR_FAULT ){
return pCur->skip;
}
clearCursorPosition(pCur);
}
pRoot = pCur->pPage;
if( pRoot && pRoot->pgno==pCur->pgnoRoot ){
assert( pRoot->isInit );
}else{
if(
SQLITE_OK!=(rc = getAndInitPage(pBt, pCur->pgnoRoot, &pRoot, 0))
){
pCur->eState = CURSOR_INVALID;
return rc;
}
releasePage(pCur->pPage);
pCur->pPage = pRoot;
}
pCur->idx = 0;
pCur->info.nSize = 0;
pCur->atLast = 0;
pCur->validNKey = 0;
if( pRoot->nCell==0 && !pRoot->leaf ){
Pgno subpage;
assert( pRoot->pgno==1 );
subpage = get4byte(&pRoot->aData[pRoot->hdrOffset+8]);
assert( subpage>0 );
pCur->eState = CURSOR_VALID;
rc = moveToChild(pCur, subpage);
}
pCur->eState = ((pCur->pPage->nCell>0)?CURSOR_VALID:CURSOR_INVALID);
return rc;
}
/*
** Move the cursor down to the left-most leaf entry beneath the
** entry to which it is currently pointing.
**
** The left-most leaf is the one with the smallest key - the first
** in ascending order.
*/
static int moveToLeftmost(BtCursor *pCur){
Pgno pgno;
int rc = SQLITE_OK;
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
pgno = get4byte(findCell(pPage, pCur->idx));
rc = moveToChild(pCur, pgno);
}
return rc;
}
/*
** Move the cursor down to the right-most leaf entry beneath the
** page to which it is currently pointing. Notice the difference
** between moveToLeftmost() and moveToRightmost(). moveToLeftmost()
** finds the left-most entry beneath the *entry* whereas moveToRightmost()
** finds the right-most entry beneath the *page*.
**
** The right-most entry is the one with the largest key - the last
** key in ascending order.
*/
static int moveToRightmost(BtCursor *pCur){
Pgno pgno;
int rc = SQLITE_OK;
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
pCur->idx = pPage->nCell;
rc = moveToChild(pCur, pgno);
}
if( rc==SQLITE_OK ){
pCur->idx = pPage->nCell - 1;
pCur->info.nSize = 0;
pCur->validNKey = 0;
}
return SQLITE_OK;
}
/* Move the cursor to the first entry in the table. Return SQLITE_OK
** on success. Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeFirst(BtCursor *pCur, int *pRes){
int rc;
assert( cursorHoldsMutex(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
rc = moveToRoot(pCur);
if( rc==SQLITE_OK ){
if( pCur->eState==CURSOR_INVALID ){
assert( pCur->pPage->nCell==0 );
*pRes = 1;
rc = SQLITE_OK;
}else{
assert( pCur->pPage->nCell>0 );
*pRes = 0;
rc = moveToLeftmost(pCur);
}
}
return rc;
}
/* Move the cursor to the last entry in the table. Return SQLITE_OK
** on success. Set *pRes to 0 if the cursor actually points to something
** or set *pRes to 1 if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
int rc;
assert( cursorHoldsMutex(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
rc = moveToRoot(pCur);
if( rc==SQLITE_OK ){
if( CURSOR_INVALID==pCur->eState ){
assert( pCur->pPage->nCell==0 );
*pRes = 1;
}else{
assert( pCur->eState==CURSOR_VALID );
*pRes = 0;
rc = moveToRightmost(pCur);
getCellInfo(pCur);
pCur->atLast = rc==SQLITE_OK;
}
}
return rc;
}
/* Move the cursor so that it points to an entry near the key
** specified by pKey/nKey/pUnKey. Return a success code.
**
** For INTKEY tables, only the nKey parameter is used. pKey
** and pUnKey must be NULL. For index tables, either pUnKey
** must point to a key that has already been unpacked, or else
** pKey/nKey describes a blob containing the key.
**
** If an exact match is not found, then the cursor is always
** left pointing at a leaf page which would hold the entry if it
** were present. The cursor might point to an entry that comes
** before or after the key.
**
** The result of comparing the key with the entry to which the
** cursor is written to *pRes if pRes!=NULL. The meaning of
** this value is as follows:
**
** *pRes<0 The cursor is left pointing at an entry that
** is smaller than pKey or if the table is empty
** and the cursor is therefore left point to nothing.
**
** *pRes==0 The cursor is left pointing at an entry that
** exactly matches pKey.
**
** *pRes>0 The cursor is left pointing at an entry that
** is larger than pKey.
**
*/
SQLITE_PRIVATE int sqlite3BtreeMoveto(
BtCursor *pCur, /* The cursor to be moved */
const void *pKey, /* The key content for indices. Not used by tables */
UnpackedRecord *pUnKey,/* Unpacked version of pKey */
i64 nKey, /* Size of pKey. Or the key for tables */
int biasRight, /* If true, bias the search to the high end */
int *pRes /* Search result flag */
){
int rc;
char aSpace[200];
assert( cursorHoldsMutex(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
/* If the cursor is already positioned at the point we are trying
** to move to, then just return without doing any work */
if( pCur->eState==CURSOR_VALID && pCur->validNKey && pCur->pPage->intKey ){
if( pCur->info.nKey==nKey ){
*pRes = 0;
return SQLITE_OK;
}
if( pCur->atLast && pCur->info.nKey<nKey ){
*pRes = -1;
return SQLITE_OK;
}
}
rc = moveToRoot(pCur);
if( rc ){
return rc;
}
assert( pCur->pPage );
assert( pCur->pPage->isInit );
if( pCur->eState==CURSOR_INVALID ){
*pRes = -1;
assert( pCur->pPage->nCell==0 );
return SQLITE_OK;
}
if( pCur->pPage->intKey ){
/* We are given an SQL table to search. The key is the integer
** rowid contained in nKey. pKey and pUnKey should both be NULL */
assert( pUnKey==0 );
assert( pKey==0 );
}else if( pUnKey==0 ){
/* We are to search an SQL index using a key encoded as a blob.
** The blob is found at pKey and is nKey bytes in length. Unpack
** this key so that we can use it. */
assert( pKey!=0 );
pUnKey = sqlite3VdbeRecordUnpack(pCur->pKeyInfo, nKey, pKey,
aSpace, sizeof(aSpace));
if( pUnKey==0 ) return SQLITE_NOMEM;
}else{
/* We are to search an SQL index using a key that is already unpacked
** and handed to us in pUnKey. */
assert( pKey==0 );
}
for(;;){
int lwr, upr;
Pgno chldPg;
MemPage *pPage = pCur->pPage;
int c = -1; /* pRes return if table is empty must be -1 */
lwr = 0;
upr = pPage->nCell-1;
if( !pPage->intKey && pUnKey==0 ){
rc = SQLITE_CORRUPT_BKPT;
goto moveto_finish;
}
if( biasRight ){
pCur->idx = upr;
}else{
pCur->idx = (upr+lwr)/2;
}
if( lwr<=upr ) for(;;){
void *pCellKey;
sqlite-amalgamation.c view on Meta::CPAN
c = sqlite3VdbeRecordCompare(nCellKey, pCellKey, pUnKey);
sqlite3_free(pCellKey);
if( rc ) goto moveto_finish;
}
}
if( c==0 ){
pCur->info.nKey = nCellKey;
if( pPage->intKey && !pPage->leaf ){
lwr = pCur->idx;
upr = lwr - 1;
break;
}else{
if( pRes ) *pRes = 0;
rc = SQLITE_OK;
goto moveto_finish;
}
}
if( c<0 ){
lwr = pCur->idx+1;
}else{
upr = pCur->idx-1;
}
if( lwr>upr ){
pCur->info.nKey = nCellKey;
break;
}
pCur->idx = (lwr+upr)/2;
}
assert( lwr==upr+1 );
assert( pPage->isInit );
if( pPage->leaf ){
chldPg = 0;
}else if( lwr>=pPage->nCell ){
chldPg = get4byte(&pPage->aData[pPage->hdrOffset+8]);
}else{
chldPg = get4byte(findCell(pPage, lwr));
}
if( chldPg==0 ){
assert( pCur->idx>=0 && pCur->idx<pCur->pPage->nCell );
if( pRes ) *pRes = c;
rc = SQLITE_OK;
goto moveto_finish;
}
pCur->idx = lwr;
pCur->info.nSize = 0;
pCur->validNKey = 0;
rc = moveToChild(pCur, chldPg);
if( rc ) goto moveto_finish;
}
moveto_finish:
if( pKey ){
/* If we created our own unpacked key at the top of this
** procedure, then destroy that key before returning. */
sqlite3VdbeDeleteUnpackedRecord(pUnKey);
}
return rc;
}
/*
** Return TRUE if the cursor is not pointing at an entry of the table.
**
** TRUE will be returned after a call to sqlite3BtreeNext() moves
** past the last entry in the table or sqlite3BtreePrev() moves past
** the first entry. TRUE is also returned if the table is empty.
*/
SQLITE_PRIVATE int sqlite3BtreeEof(BtCursor *pCur){
/* TODO: What if the cursor is in CURSOR_REQUIRESEEK but all table entries
** have been deleted? This API will need to change to return an error code
** as well as the boolean result value.
*/
return (CURSOR_VALID!=pCur->eState);
}
/*
** Return the database connection handle for a cursor.
*/
SQLITE_PRIVATE sqlite3 *sqlite3BtreeCursorDb(const BtCursor *pCur){
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
return pCur->pBtree->db;
}
/*
** Advance the cursor to the next entry in the database. If
** successful then set *pRes=0. If the cursor
** was already pointing to the last entry in the database before
** this routine was called, then set *pRes=1.
*/
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
int rc;
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
assert( pRes!=0 );
pPage = pCur->pPage;
if( CURSOR_INVALID==pCur->eState ){
*pRes = 1;
return SQLITE_OK;
}
if( pCur->skip>0 ){
pCur->skip = 0;
*pRes = 0;
return SQLITE_OK;
}
pCur->skip = 0;
assert( pPage->isInit );
assert( pCur->idx<pPage->nCell );
pCur->idx++;
pCur->info.nSize = 0;
pCur->validNKey = 0;
if( pCur->idx>=pPage->nCell ){
if( !pPage->leaf ){
rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
if( rc ) return rc;
rc = moveToLeftmost(pCur);
*pRes = 0;
return rc;
}
do{
if( sqlite3BtreeIsRootPage(pPage) ){
*pRes = 1;
pCur->eState = CURSOR_INVALID;
return SQLITE_OK;
}
sqlite3BtreeMoveToParent(pCur);
pPage = pCur->pPage;
}while( pCur->idx>=pPage->nCell );
*pRes = 0;
if( pPage->intKey ){
rc = sqlite3BtreeNext(pCur, pRes);
}else{
rc = SQLITE_OK;
}
return rc;
}
*pRes = 0;
if( pPage->leaf ){
return SQLITE_OK;
}
rc = moveToLeftmost(pCur);
return rc;
}
/*
** Step the cursor to the back to the previous entry in the database. If
** successful then set *pRes=0. If the cursor
** was already pointing to the first entry in the database before
** this routine was called, then set *pRes=1.
*/
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
int rc;
Pgno pgno;
MemPage *pPage;
assert( cursorHoldsMutex(pCur) );
rc = restoreCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
pCur->atLast = 0;
if( CURSOR_INVALID==pCur->eState ){
*pRes = 1;
return SQLITE_OK;
}
if( pCur->skip<0 ){
pCur->skip = 0;
*pRes = 0;
return SQLITE_OK;
}
pCur->skip = 0;
pPage = pCur->pPage;
assert( pPage->isInit );
assert( pCur->idx>=0 );
if( !pPage->leaf ){
pgno = get4byte( findCell(pPage, pCur->idx) );
rc = moveToChild(pCur, pgno);
if( rc ){
return rc;
}
rc = moveToRightmost(pCur);
}else{
while( pCur->idx==0 ){
if( sqlite3BtreeIsRootPage(pPage) ){
pCur->eState = CURSOR_INVALID;
*pRes = 1;
return SQLITE_OK;
}
sqlite3BtreeMoveToParent(pCur);
pPage = pCur->pPage;
}
pCur->idx--;
pCur->info.nSize = 0;
pCur->validNKey = 0;
if( pPage->intKey && !pPage->leaf ){
rc = sqlite3BtreePrevious(pCur, pRes);
}else{
rc = SQLITE_OK;
}
}
*pRes = 0;
return rc;
}
/*
** Allocate a new page from the database file.
**
** The new page is marked as dirty. (In other words, sqlite3PagerWrite()
** has already been called on the new page.) The new page has also
** been referenced and the calling routine is responsible for calling
** sqlite3PagerUnref() on the new page when it is done.
**
** SQLITE_OK is returned on success. Any other return value indicates
** an error. *ppPage and *pPgno are undefined in the event of an error.
** Do not invoke sqlite3PagerUnref() on *ppPage if an error is returned.
sqlite-amalgamation.c view on Meta::CPAN
memcpy(cdata, &data[hdr], pPage->cellOffset+2*pPage->nCell-hdr);
memcpy(&cdata[brk], &data[brk], usableSize-brk);
if( pChild->isInit ) return SQLITE_CORRUPT;
rc = sqlite3BtreeInitPage(pChild, pPage);
if( rc ) goto balancedeeper_out;
memcpy(pChild->aOvfl, pPage->aOvfl, pPage->nOverflow*sizeof(pPage->aOvfl[0]));
pChild->nOverflow = pPage->nOverflow;
if( pChild->nOverflow ){
pChild->nFree = 0;
}
assert( pChild->nCell==pPage->nCell );
zeroPage(pPage, pChild->aData[0] & ~PTF_LEAF);
put4byte(&pPage->aData[pPage->hdrOffset+8], pgnoChild);
TRACE(("BALANCE: copy root %d into %d\n", pPage->pgno, pChild->pgno));
if( ISAUTOVACUUM ){
int i;
rc = ptrmapPut(pBt, pChild->pgno, PTRMAP_BTREE, pPage->pgno);
if( rc ) goto balancedeeper_out;
for(i=0; i<pChild->nCell; i++){
rc = ptrmapPutOvfl(pChild, i);
if( rc!=SQLITE_OK ){
goto balancedeeper_out;
}
}
rc = reparentChildPages(pChild, 1);
}
if( rc==SQLITE_OK ){
rc = balance_nonroot(pChild);
}
balancedeeper_out:
releasePage(pChild);
return rc;
}
/*
** Decide if the page pPage needs to be balanced. If balancing is
** required, call the appropriate balancing routine.
*/
static int balance(MemPage *pPage, int insert){
int rc = SQLITE_OK;
assert( sqlite3_mutex_held(pPage->pBt->mutex) );
if( pPage->pParent==0 ){
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc==SQLITE_OK && pPage->nOverflow>0 ){
rc = balance_deeper(pPage);
}
if( rc==SQLITE_OK && pPage->nCell==0 ){
rc = balance_shallower(pPage);
}
}else{
if( pPage->nOverflow>0 ||
(!insert && pPage->nFree>pPage->pBt->usableSize*2/3) ){
rc = balance_nonroot(pPage);
}
}
return rc;
}
/*
** This routine checks all cursors that point to table pgnoRoot.
** If any of those cursors were opened with wrFlag==0 in a different
** database connection (a database connection that shares the pager
** cache with the current connection) and that other connection
** is not in the ReadUncommmitted state, then this routine returns
** SQLITE_LOCKED.
**
** As well as cursors with wrFlag==0, cursors with wrFlag==1 and
** isIncrblobHandle==1 are also considered 'read' cursors. Incremental
** blob cursors are used for both reading and writing.
**
** When pgnoRoot is the root page of an intkey table, this function is also
** responsible for invalidating incremental blob cursors when the table row
** on which they are opened is deleted or modified. Cursors are invalidated
** according to the following rules:
**
** 1) When BtreeClearTable() is called to completely delete the contents
** of a B-Tree table, pExclude is set to zero and parameter iRow is
** set to non-zero. In this case all incremental blob cursors open
** on the table rooted at pgnoRoot are invalidated.
**
** 2) When BtreeInsert(), BtreeDelete() or BtreePutData() is called to
** modify a table row via an SQL statement, pExclude is set to the
** write cursor used to do the modification and parameter iRow is set
** to the integer row id of the B-Tree entry being modified. Unless
** pExclude is itself an incremental blob cursor, then all incremental
** blob cursors open on row iRow of the B-Tree are invalidated.
**
** 3) If both pExclude and iRow are set to zero, no incremental blob
** cursors are invalidated.
*/
static int checkReadLocks(
Btree *pBtree,
Pgno pgnoRoot,
BtCursor *pExclude,
i64 iRow
){
BtCursor *p;
BtShared *pBt = pBtree->pBt;
sqlite3 *db = pBtree->db;
assert( sqlite3BtreeHoldsMutex(pBtree) );
for(p=pBt->pCursor; p; p=p->pNext){
if( p==pExclude ) continue;
if( p->pgnoRoot!=pgnoRoot ) continue;
#ifndef SQLITE_OMIT_INCRBLOB
if( p->isIncrblobHandle && (
(!pExclude && iRow)
|| (pExclude && !pExclude->isIncrblobHandle && p->info.nKey==iRow)
)){
p->eState = CURSOR_INVALID;
}
#endif
if( p->eState!=CURSOR_VALID ) continue;
if( p->wrFlag==0
#ifndef SQLITE_OMIT_INCRBLOB
|| p->isIncrblobHandle
#endif
){
sqlite3 *dbOther = p->pBtree->db;
if( dbOther==0 ||
(dbOther!=db && (dbOther->flags & SQLITE_ReadUncommitted)==0) ){
return SQLITE_LOCKED;
}
}
}
return SQLITE_OK;
}
/*
** Insert a new record into the BTree. The key is given by (pKey,nKey)
** and the data is given by (pData,nData). The cursor is used only to
** define what table the record should be inserted into. The cursor
** is left pointing at a random location.
**
** For an INTKEY table, only the nKey value of the key is used. pKey is
** ignored. For a ZERODATA table, the pData and nData are both ignored.
*/
SQLITE_PRIVATE int sqlite3BtreeInsert(
BtCursor *pCur, /* Insert data into the table of this cursor */
const void *pKey, i64 nKey, /* The key of the new record */
const void *pData, int nData, /* The data of the new record */
int nZero, /* Number of extra 0 bytes to append to data */
int appendBias /* True if this is likely an append */
){
int rc;
int loc;
int szNew;
MemPage *pPage;
Btree *p = pCur->pBtree;
BtShared *pBt = p->pBt;
unsigned char *oldCell;
unsigned char *newCell = 0;
assert( cursorHoldsMutex(pCur) );
if( pBt->inTransaction!=TRANS_WRITE ){
/* Must start a transaction before doing an insert */
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
return rc;
}
assert( !pBt->readOnly );
if( !pCur->wrFlag ){
return SQLITE_PERM; /* Cursor not open for writing */
}
if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur, nKey) ){
return SQLITE_LOCKED; /* The table pCur points to has a read lock */
}
if( pCur->eState==CURSOR_FAULT ){
return pCur->skip;
}
/* Save the positions of any other cursors open on this table */
clearCursorPosition(pCur);
if(
SQLITE_OK!=(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur)) ||
SQLITE_OK!=(rc = sqlite3BtreeMoveto(pCur, pKey, 0, nKey, appendBias, &loc))
){
return rc;
}
pPage = pCur->pPage;
assert( pPage->intKey || nKey>=0 );
assert( pPage->leaf || !pPage->intKey );
TRACE(("INSERT: table=%d nkey=%lld ndata=%d page=%d %s\n",
pCur->pgnoRoot, nKey, nData, pPage->pgno,
loc==0 ? "overwrite" : "new entry"));
assert( pPage->isInit );
allocateTempSpace(pBt);
newCell = pBt->pTmpSpace;
if( newCell==0 ) return SQLITE_NOMEM;
rc = fillInCell(pPage, newCell, pKey, nKey, pData, nData, nZero, &szNew);
if( rc ) goto end_insert;
assert( szNew==cellSizePtr(pPage, newCell) );
assert( szNew<=MX_CELL_SIZE(pBt) );
if( loc==0 && CURSOR_VALID==pCur->eState ){
u16 szOld;
assert( pCur->idx>=0 && pCur->idx<pPage->nCell );
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ){
goto end_insert;
}
oldCell = findCell(pPage, pCur->idx);
if( !pPage->leaf ){
memcpy(newCell, oldCell, 4);
}
szOld = cellSizePtr(pPage, oldCell);
rc = clearCell(pPage, oldCell);
if( rc ) goto end_insert;
dropCell(pPage, pCur->idx, szOld);
}else if( loc<0 && pPage->nCell>0 ){
assert( pPage->leaf );
pCur->idx++;
pCur->info.nSize = 0;
pCur->validNKey = 0;
}else{
assert( pPage->leaf );
}
rc = insertCell(pPage, pCur->idx, newCell, szNew, 0, 0);
if( rc!=SQLITE_OK ) goto end_insert;
rc = balance(pPage, 1);
if( rc==SQLITE_OK ){
moveToRoot(pCur);
}
end_insert:
return rc;
}
/*
** Delete the entry that the cursor is pointing to. The cursor
** is left pointing at a random location.
*/
SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor *pCur){
MemPage *pPage = pCur->pPage;
unsigned char *pCell;
int rc;
Pgno pgnoChild = 0;
Btree *p = pCur->pBtree;
BtShared *pBt = p->pBt;
assert( cursorHoldsMutex(pCur) );
assert( pPage->isInit );
if( pBt->inTransaction!=TRANS_WRITE ){
/* Must start a transaction before doing a delete */
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
return rc;
}
assert( !pBt->readOnly );
if( pCur->eState==CURSOR_FAULT ){
return pCur->skip;
}
if( pCur->idx >= pPage->nCell ){
return SQLITE_ERROR; /* The cursor is not pointing to anything */
}
if( !pCur->wrFlag ){
return SQLITE_PERM; /* Did not open this cursor for writing */
}
if( checkReadLocks(pCur->pBtree, pCur->pgnoRoot, pCur, pCur->info.nKey) ){
return SQLITE_LOCKED; /* The table pCur points to has a read lock */
}
/* Restore the current cursor position (a no-op if the cursor is not in
** CURSOR_REQUIRESEEK state) and save the positions of any other cursors
** open on the same table. Then call sqlite3PagerWrite() on the page
** that the entry will be deleted from.
*/
if(
(rc = restoreCursorPosition(pCur))!=0 ||
(rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur))!=0 ||
(rc = sqlite3PagerWrite(pPage->pDbPage))!=0
){
return rc;
}
/* Locate the cell within its page and leave pCell pointing to the
** data. The clearCell() call frees any overflow pages associated with the
** cell. The cell itself is still intact.
*/
pCell = findCell(pPage, pCur->idx);
if( !pPage->leaf ){
pgnoChild = get4byte(pCell);
}
rc = clearCell(pPage, pCell);
if( rc ){
return rc;
}
if( !pPage->leaf ){
/*
** The entry we are about to delete is not a leaf so if we do not
** do something we will leave a hole on an internal page.
** We have to fill the hole by moving in a cell from a leaf. The
** next Cell after the one to be deleted is guaranteed to exist and
** to be a leaf so we can use it.
*/
BtCursor leafCur;
unsigned char *pNext;
int notUsed;
unsigned char *tempCell = 0;
assert( !pPage->intKey );
sqlite3BtreeGetTempCursor(pCur, &leafCur);
rc = sqlite3BtreeNext(&leafCur, ¬Used);
if( rc==SQLITE_OK ){
rc = sqlite3PagerWrite(leafCur.pPage->pDbPage);
}
if( rc==SQLITE_OK ){
u16 szNext;
TRACE(("DELETE: table=%d delete internal from %d replace from leaf %d\n",
pCur->pgnoRoot, pPage->pgno, leafCur.pPage->pgno));
dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
pNext = findCell(leafCur.pPage, leafCur.idx);
szNext = cellSizePtr(leafCur.pPage, pNext);
assert( MX_CELL_SIZE(pBt)>=szNext+4 );
allocateTempSpace(pBt);
tempCell = pBt->pTmpSpace;
if( tempCell==0 ){
rc = SQLITE_NOMEM;
}
if( rc==SQLITE_OK ){
rc = insertCell(pPage, pCur->idx, pNext-4, szNext+4, tempCell, 0);
}
if( rc==SQLITE_OK ){
put4byte(findOverflowCell(pPage, pCur->idx), pgnoChild);
rc = balance(pPage, 0);
}
if( rc==SQLITE_OK ){
dropCell(leafCur.pPage, leafCur.idx, szNext);
rc = balance(leafCur.pPage, 0);
}
}
sqlite3BtreeReleaseTempCursor(&leafCur);
}else{
TRACE(("DELETE: table=%d delete from leaf %d\n",
pCur->pgnoRoot, pPage->pgno));
dropCell(pPage, pCur->idx, cellSizePtr(pPage, pCell));
rc = balance(pPage, 0);
}
if( rc==SQLITE_OK ){
moveToRoot(pCur);
}
return rc;
}
/*
** Create a new BTree table. Write into *piTable the page
** number for the root page of the new table.
**
** The type of type is determined by the flags parameter. Only the
** following values of flags are currently in use. Other values for
** flags might not work:
**
** BTREE_INTKEY|BTREE_LEAFDATA Used for SQL tables with rowid keys
** BTREE_ZERODATA Used for SQL indices
*/
static int btreeCreateTable(Btree *p, int *piTable, int flags){
BtShared *pBt = p->pBt;
MemPage *pRoot;
Pgno pgnoRoot;
int rc;
assert( sqlite3BtreeHoldsMutex(p) );
if( pBt->inTransaction!=TRANS_WRITE ){
/* Must start a transaction first */
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
return rc;
}
assert( !pBt->readOnly );
#ifdef SQLITE_OMIT_AUTOVACUUM
rc = allocateBtreePage(pBt, &pRoot, &pgnoRoot, 1, 0);
if( rc ){
return rc;
}
#else
if( pBt->autoVacuum ){
Pgno pgnoMove; /* Move a page here to make room for the root-page */
MemPage *pPageMove; /* The page to move to. */
/* Creating a new table may probably require moving an existing database
** to make room for the new tables root page. In case this page turns
** out to be an overflow page, delete all overflow page-map caches
** held by open cursors.
*/
invalidateAllOverflowCache(pBt);
/* Read the value of meta[3] from the database to determine where the
** root page of the new table should go. meta[3] is the largest root-page
** created so far, so the new root-page is (meta[3]+1).
*/
rc = sqlite3BtreeGetMeta(p, 4, &pgnoRoot);
if( rc!=SQLITE_OK ){
return rc;
}
pgnoRoot++;
/* The new root-page may not be allocated on a pointer-map page, or the
** PENDING_BYTE page.
*/
while( pgnoRoot==PTRMAP_PAGENO(pBt, pgnoRoot) ||
pgnoRoot==PENDING_BYTE_PAGE(pBt) ){
pgnoRoot++;
}
assert( pgnoRoot>=3 );
/* Allocate a page. The page that currently resides at pgnoRoot will
** be moved to the allocated page (unless the allocated page happens
** to reside at pgnoRoot).
*/
rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
if( rc!=SQLITE_OK ){
return rc;
}
if( pgnoMove!=pgnoRoot ){
/* pgnoRoot is the page that will be used for the root-page of
** the new table (assuming an error did not occur). But we were
** allocated pgnoMove. If required (i.e. if it was not allocated
** by extending the file), the current page at position pgnoMove
** is already journaled.
*/
u8 eType;
Pgno iPtrPage;
releasePage(pPageMove);
/* Move the page currently at pgnoRoot to pgnoMove. */
rc = sqlite3BtreeGetPage(pBt, pgnoRoot, &pRoot, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = ptrmapGet(pBt, pgnoRoot, &eType, &iPtrPage);
if( rc!=SQLITE_OK || eType==PTRMAP_ROOTPAGE || eType==PTRMAP_FREEPAGE ){
releasePage(pRoot);
return rc;
}
assert( eType!=PTRMAP_ROOTPAGE );
assert( eType!=PTRMAP_FREEPAGE );
rc = sqlite3PagerWrite(pRoot->pDbPage);
if( rc!=SQLITE_OK ){
releasePage(pRoot);
return rc;
}
sqlite-amalgamation.c view on Meta::CPAN
int rc;
sqlite3BtreeEnter(p);
p->pBt->db = p->db;
rc = btreeCreateTable(p, piTable, flags);
sqlite3BtreeLeave(p);
return rc;
}
/*
** Erase the given database page and all its children. Return
** the page to the freelist.
*/
static int clearDatabasePage(
BtShared *pBt, /* The BTree that contains the table */
Pgno pgno, /* Page number to clear */
MemPage *pParent, /* Parent page. NULL for the root */
int freePageFlag /* Deallocate page if true */
){
MemPage *pPage = 0;
int rc;
unsigned char *pCell;
int i;
assert( sqlite3_mutex_held(pBt->mutex) );
if( pgno>pagerPagecount(pBt->pPager) ){
return SQLITE_CORRUPT_BKPT;
}
rc = getAndInitPage(pBt, pgno, &pPage, pParent);
if( rc ) goto cleardatabasepage_out;
for(i=0; i<pPage->nCell; i++){
pCell = findCell(pPage, i);
if( !pPage->leaf ){
rc = clearDatabasePage(pBt, get4byte(pCell), pPage->pParent, 1);
if( rc ) goto cleardatabasepage_out;
}
rc = clearCell(pPage, pCell);
if( rc ) goto cleardatabasepage_out;
}
if( !pPage->leaf ){
rc = clearDatabasePage(pBt, get4byte(&pPage->aData[8]), pPage->pParent, 1);
if( rc ) goto cleardatabasepage_out;
}
if( freePageFlag ){
rc = freePage(pPage);
}else if( (rc = sqlite3PagerWrite(pPage->pDbPage))==0 ){
zeroPage(pPage, pPage->aData[0] | PTF_LEAF);
}
cleardatabasepage_out:
releasePage(pPage);
return rc;
}
/*
** Delete all information from a single table in the database. iTable is
** the page number of the root of the table. After this routine returns,
** the root page is empty, but still exists.
**
** This routine will fail with SQLITE_LOCKED if there are any open
** read cursors on the table. Open write cursors are moved to the
** root of the table.
*/
SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree *p, int iTable){
int rc;
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
pBt->db = p->db;
if( p->inTrans!=TRANS_WRITE ){
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}else if( (rc = checkReadLocks(p, iTable, 0, 1))!=SQLITE_OK ){
/* nothing to do */
}else if( SQLITE_OK!=(rc = saveAllCursors(pBt, iTable, 0)) ){
/* nothing to do */
}else{
rc = clearDatabasePage(pBt, (Pgno)iTable, 0, 0);
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** Erase all information in a table and add the root of the table to
** the freelist. Except, the root of the principle table (the one on
** page 1) is never added to the freelist.
**
** This routine will fail with SQLITE_LOCKED if there are any open
** cursors on the table.
**
** If AUTOVACUUM is enabled and the page at iTable is not the last
** root page in the database file, then the last root page
** in the database file is moved into the slot formerly occupied by
** iTable and that last slot formerly occupied by the last root page
** is added to the freelist instead of iTable. In this say, all
** root pages are kept at the beginning of the database file, which
** is necessary for AUTOVACUUM to work right. *piMoved is set to the
** page number that used to be the last root page in the file before
** the move. If no page gets moved, *piMoved is set to 0.
** The last root page is recorded in meta[3] and the value of
** meta[3] is updated by this procedure.
*/
static int btreeDropTable(Btree *p, int iTable, int *piMoved){
int rc;
MemPage *pPage = 0;
BtShared *pBt = p->pBt;
assert( sqlite3BtreeHoldsMutex(p) );
if( p->inTrans!=TRANS_WRITE ){
return pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}
/* It is illegal to drop a table if any cursors are open on the
** database. This is because in auto-vacuum mode the backend may
** need to move another root-page to fill a gap left by the deleted
** root page. If an open cursor was using this page a problem would
** occur.
*/
if( pBt->pCursor ){
return SQLITE_LOCKED;
}
rc = sqlite3BtreeGetPage(pBt, (Pgno)iTable, &pPage, 0);
if( rc ) return rc;
rc = sqlite3BtreeClearTable(p, iTable);
if( rc ){
releasePage(pPage);
return rc;
}
*piMoved = 0;
if( iTable>1 ){
#ifdef SQLITE_OMIT_AUTOVACUUM
rc = freePage(pPage);
releasePage(pPage);
#else
if( pBt->autoVacuum ){
Pgno maxRootPgno;
rc = sqlite3BtreeGetMeta(p, 4, &maxRootPgno);
if( rc!=SQLITE_OK ){
releasePage(pPage);
return rc;
}
if( iTable==maxRootPgno ){
/* If the table being dropped is the table with the largest root-page
** number in the database, put the root page on the free list.
*/
rc = freePage(pPage);
releasePage(pPage);
if( rc!=SQLITE_OK ){
return rc;
}
}else{
/* The table being dropped does not have the largest root-page
** number in the database. So move the page that does into the
** gap left by the deleted root-page.
*/
MemPage *pMove;
releasePage(pPage);
rc = sqlite3BtreeGetPage(pBt, maxRootPgno, &pMove, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = relocatePage(pBt, pMove, PTRMAP_ROOTPAGE, 0, iTable, 0);
releasePage(pMove);
if( rc!=SQLITE_OK ){
return rc;
}
rc = sqlite3BtreeGetPage(pBt, maxRootPgno, &pMove, 0);
if( rc!=SQLITE_OK ){
return rc;
}
rc = freePage(pMove);
releasePage(pMove);
sqlite-amalgamation.c view on Meta::CPAN
sqlite3BtreeLeave(p);
return rc;
}
assert( idx>=0 && idx<=15 );
rc = sqlite3PagerGet(pBt->pPager, 1, &pDbPage);
if( rc ){
sqlite3BtreeLeave(p);
return rc;
}
pP1 = (unsigned char *)sqlite3PagerGetData(pDbPage);
*pMeta = get4byte(&pP1[36 + idx*4]);
sqlite3PagerUnref(pDbPage);
/* If autovacuumed is disabled in this build but we are trying to
** access an autovacuumed database, then make the database readonly.
*/
#ifdef SQLITE_OMIT_AUTOVACUUM
if( idx==4 && *pMeta>0 ) pBt->readOnly = 1;
#endif
/* Grab the read-lock on page 1. */
rc = lockTable(p, 1, READ_LOCK);
sqlite3BtreeLeave(p);
return rc;
}
/*
** Write meta-information back into the database. Meta[0] is
** read-only and may not be written.
*/
SQLITE_PRIVATE int sqlite3BtreeUpdateMeta(Btree *p, int idx, u32 iMeta){
BtShared *pBt = p->pBt;
unsigned char *pP1;
int rc;
assert( idx>=1 && idx<=15 );
sqlite3BtreeEnter(p);
pBt->db = p->db;
if( p->inTrans!=TRANS_WRITE ){
rc = pBt->readOnly ? SQLITE_READONLY : SQLITE_ERROR;
}else{
assert( pBt->pPage1!=0 );
pP1 = pBt->pPage1->aData;
rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
if( rc==SQLITE_OK ){
put4byte(&pP1[36 + idx*4], iMeta);
#ifndef SQLITE_OMIT_AUTOVACUUM
if( idx==7 ){
assert( pBt->autoVacuum || iMeta==0 );
assert( iMeta==0 || iMeta==1 );
pBt->incrVacuum = iMeta;
}
#endif
}
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** Return the flag byte at the beginning of the page that the cursor
** is currently pointing to.
*/
SQLITE_PRIVATE int sqlite3BtreeFlags(BtCursor *pCur){
/* TODO: What about CURSOR_REQUIRESEEK state? Probably need to call
** restoreCursorPosition() here.
*/
MemPage *pPage;
restoreCursorPosition(pCur);
pPage = pCur->pPage;
assert( cursorHoldsMutex(pCur) );
assert( pPage->pBt==pCur->pBt );
return pPage ? pPage->aData[pPage->hdrOffset] : 0;
}
/*
** Return the pager associated with a BTree. This routine is used for
** testing and debugging only.
*/
SQLITE_PRIVATE Pager *sqlite3BtreePager(Btree *p){
return p->pBt->pPager;
}
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Append a message to the error message string.
*/
static void checkAppendMsg(
IntegrityCk *pCheck,
char *zMsg1,
const char *zFormat,
...
){
va_list ap;
if( !pCheck->mxErr ) return;
pCheck->mxErr--;
pCheck->nErr++;
va_start(ap, zFormat);
if( pCheck->errMsg.nChar ){
sqlite3StrAccumAppend(&pCheck->errMsg, "\n", 1);
}
if( zMsg1 ){
sqlite3StrAccumAppend(&pCheck->errMsg, zMsg1, -1);
}
sqlite3VXPrintf(&pCheck->errMsg, 1, zFormat, ap);
va_end(ap);
if( pCheck->errMsg.mallocFailed ){
pCheck->mallocFailed = 1;
}
}
#endif /* SQLITE_OMIT_INTEGRITY_CHECK */
#ifndef SQLITE_OMIT_INTEGRITY_CHECK
/*
** Add 1 to the reference count for page iPage. If this is the second
** reference to the page, add an error message to pCheck->zErrMsg.
** Return 1 if there are 2 ore more references to the page and 0 if
** if this is the first reference to the page.
**
** Also check that the page number is in bounds.
*/
static int checkRef(IntegrityCk *pCheck, int iPage, char *zContext){
if( iPage==0 ) return 1;
if( iPage>pCheck->nPage || iPage<0 ){
checkAppendMsg(pCheck, zContext, "invalid page number %d", iPage);
return 1;
}
if( pCheck->anRef[iPage]==1 ){
checkAppendMsg(pCheck, zContext, "2nd reference to page %d", iPage);
return 1;
sqlite-amalgamation.c view on Meta::CPAN
**
** If the nBytes parameter is 0 and the blob of memory has not yet been
** allocated, a null pointer is returned. If the blob has already been
** allocated, it is returned as normal.
**
** Just before the shared-btree is closed, the function passed as the
** xFree argument when the memory allocation was made is invoked on the
** blob of allocated memory. This function should not call sqlite3_free()
** on the memory, the btree layer does that.
*/
SQLITE_PRIVATE void *sqlite3BtreeSchema(Btree *p, int nBytes, void(*xFree)(void *)){
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
if( !pBt->pSchema && nBytes ){
pBt->pSchema = sqlite3MallocZero(nBytes);
pBt->xFreeSchema = xFree;
}
sqlite3BtreeLeave(p);
return pBt->pSchema;
}
/*
** Return true if another user of the same shared btree as the argument
** handle holds an exclusive lock on the sqlite_master table.
*/
SQLITE_PRIVATE int sqlite3BtreeSchemaLocked(Btree *p){
int rc;
assert( sqlite3_mutex_held(p->db->mutex) );
sqlite3BtreeEnter(p);
rc = (queryTableLock(p, MASTER_ROOT, READ_LOCK)!=SQLITE_OK);
sqlite3BtreeLeave(p);
return rc;
}
#ifndef SQLITE_OMIT_SHARED_CACHE
/*
** Obtain a lock on the table whose root page is iTab. The
** lock is a write lock if isWritelock is true or a read lock
** if it is false.
*/
SQLITE_PRIVATE int sqlite3BtreeLockTable(Btree *p, int iTab, u8 isWriteLock){
int rc = SQLITE_OK;
if( p->sharable ){
u8 lockType = READ_LOCK + isWriteLock;
assert( READ_LOCK+1==WRITE_LOCK );
assert( isWriteLock==0 || isWriteLock==1 );
sqlite3BtreeEnter(p);
rc = queryTableLock(p, iTab, lockType);
if( rc==SQLITE_OK ){
rc = lockTable(p, iTab, lockType);
}
sqlite3BtreeLeave(p);
}
return rc;
}
#endif
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Argument pCsr must be a cursor opened for writing on an
** INTKEY table currently pointing at a valid table entry.
** This function modifies the data stored as part of that entry.
** Only the data content may only be modified, it is not possible
** to change the length of the data stored.
*/
SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
assert( cursorHoldsMutex(pCsr) );
assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
assert(pCsr->isIncrblobHandle);
restoreCursorPosition(pCsr);
assert( pCsr->eState!=CURSOR_REQUIRESEEK );
if( pCsr->eState!=CURSOR_VALID ){
return SQLITE_ABORT;
}
/* Check some preconditions:
** (a) the cursor is open for writing,
** (b) there is no read-lock on the table being modified and
** (c) the cursor points at a valid row of an intKey table.
*/
if( !pCsr->wrFlag ){
return SQLITE_READONLY;
}
assert( !pCsr->pBt->readOnly
&& pCsr->pBt->inTransaction==TRANS_WRITE );
if( checkReadLocks(pCsr->pBtree, pCsr->pgnoRoot, pCsr, 0) ){
return SQLITE_LOCKED; /* The table pCur points to has a read lock */
}
if( pCsr->eState==CURSOR_INVALID || !pCsr->pPage->intKey ){
return SQLITE_ERROR;
}
return accessPayload(pCsr, offset, amt, (unsigned char *)z, 0, 1);
}
/*
** Set a flag on this cursor to cache the locations of pages from the
** overflow list for the current row. This is used by cursors opened
** for incremental blob IO only.
**
** This function sets a flag only. The actual page location cache
** (stored in BtCursor.aOverflow[]) is allocated and used by function
** accessPayload() (the worker function for sqlite3BtreeData() and
** sqlite3BtreePutData()).
*/
SQLITE_PRIVATE void sqlite3BtreeCacheOverflow(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert(!pCur->isIncrblobHandle);
assert(!pCur->aOverflow);
pCur->isIncrblobHandle = 1;
}
#endif
/************** End of btree.c ***********************************************/
/************** Begin file vdbefifo.c ****************************************/
/*
** 2005 June 16
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file implements a FIFO queue of rowids used for processing
** UPDATE and DELETE statements.
**
** $Id: vdbefifo.c,v 1.8 2008/07/28 19:34:54 drh Exp $
*/
/*
** Constants FIFOSIZE_FIRST and FIFOSIZE_MAX are the initial
** number of entries in a fifo page and the maximum number of
** entries in a fifo page.
*/
#define FIFOSIZE_FIRST (((128-sizeof(FifoPage))/8)+1)
#ifdef SQLITE_MALLOC_SOFT_LIMIT
# define FIFOSIZE_MAX (((SQLITE_MALLOC_SOFT_LIMIT-sizeof(FifoPage))/8)+1)
#else
# define FIFOSIZE_MAX (((262144-sizeof(FifoPage))/8)+1)
#endif
/*
** Allocate a new FifoPage and return a pointer to it. Return NULL if
** we run out of memory. Leave space on the page for nEntry entries.
*/
static FifoPage *allocateFifoPage(sqlite3 *db, int nEntry){
FifoPage *pPage;
if( nEntry>FIFOSIZE_MAX ){
nEntry = FIFOSIZE_MAX;
}
pPage = sqlite3DbMallocRaw(db, sizeof(FifoPage) + sizeof(i64)*(nEntry-1) );
if( pPage ){
pPage->nSlot = nEntry;
pPage->iWrite = 0;
pPage->iRead = 0;
pPage->pNext = 0;
}
return pPage;
}
/*
** Initialize a Fifo structure.
*/
sqlite-amalgamation.c view on Meta::CPAN
/*
** Print the SQL that was used to generate a VDBE program.
*/
SQLITE_PRIVATE void sqlite3VdbePrintSql(Vdbe *p){
int nOp = p->nOp;
VdbeOp *pOp;
if( nOp<1 ) return;
pOp = &p->aOp[0];
if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
const char *z = pOp->p4.z;
while( isspace(*(u8*)z) ) z++;
printf("SQL: [%s]\n", z);
}
}
#endif
#if !defined(SQLITE_OMIT_TRACE) && defined(SQLITE_ENABLE_IOTRACE)
/*
** Print an IOTRACE message showing SQL content.
*/
SQLITE_PRIVATE void sqlite3VdbeIOTraceSql(Vdbe *p){
int nOp = p->nOp;
VdbeOp *pOp;
if( sqlite3IoTrace==0 ) return;
if( nOp<1 ) return;
pOp = &p->aOp[0];
if( pOp->opcode==OP_Trace && pOp->p4.z!=0 ){
int i, j;
char z[1000];
sqlite3_snprintf(sizeof(z), z, "%s", pOp->p4.z);
for(i=0; isspace((unsigned char)z[i]); i++){}
for(j=0; z[i]; i++){
if( isspace((unsigned char)z[i]) ){
if( z[i-1]!=' ' ){
z[j++] = ' ';
}
}else{
z[j++] = z[i];
}
}
z[j] = 0;
sqlite3IoTrace("SQL %s\n", z);
}
}
#endif /* !SQLITE_OMIT_TRACE && SQLITE_ENABLE_IOTRACE */
/*
** Prepare a virtual machine for execution. This involves things such
** as allocating stack space and initializing the program counter.
** After the VDBE has be prepped, it can be executed by one or more
** calls to sqlite3VdbeExec().
**
** This is the only way to move a VDBE from VDBE_MAGIC_INIT to
** VDBE_MAGIC_RUN.
*/
SQLITE_PRIVATE void sqlite3VdbeMakeReady(
Vdbe *p, /* The VDBE */
int nVar, /* Number of '?' see in the SQL statement */
int nMem, /* Number of memory cells to allocate */
int nCursor, /* Number of cursors to allocate */
int isExplain /* True if the EXPLAIN keywords is present */
){
int n;
sqlite3 *db = p->db;
assert( p!=0 );
assert( p->magic==VDBE_MAGIC_INIT );
/* There should be at least one opcode.
*/
assert( p->nOp>0 );
/* Set the magic to VDBE_MAGIC_RUN sooner rather than later. This
* is because the call to resizeOpArray() below may shrink the
* p->aOp[] array to save memory if called when in VDBE_MAGIC_RUN
* state.
*/
p->magic = VDBE_MAGIC_RUN;
/* For each cursor required, also allocate a memory cell. Memory
** cells (nMem+1-nCursor)..nMem, inclusive, will never be used by
** the vdbe program. Instead they are used to allocate space for
** Cursor/BtCursor structures. The blob of memory associated with
** cursor 0 is stored in memory cell nMem. Memory cell (nMem-1)
** stores the blob of memory associated with cursor 1, etc.
**
** See also: allocateCursor().
*/
nMem += nCursor;
/*
** Allocation space for registers.
*/
if( p->aMem==0 ){
int nArg; /* Maximum number of args passed to a user function. */
resolveP2Values(p, &nArg);
/*resizeOpArray(p, p->nOp);*/
assert( nVar>=0 );
if( isExplain && nMem<10 ){
p->nMem = nMem = 10;
}
p->aMem = sqlite3DbMallocZero(db,
nMem*sizeof(Mem) /* aMem */
+ nVar*sizeof(Mem) /* aVar */
+ nArg*sizeof(Mem*) /* apArg */
+ nVar*sizeof(char*) /* azVar */
+ nCursor*sizeof(Cursor*) + 1 /* apCsr */
);
if( !db->mallocFailed ){
p->aMem--; /* aMem[] goes from 1..nMem */
p->nMem = nMem; /* not from 0..nMem-1 */
p->aVar = &p->aMem[nMem+1];
p->nVar = nVar;
p->okVar = 0;
p->apArg = (Mem**)&p->aVar[nVar];
p->azVar = (char**)&p->apArg[nArg];
p->apCsr = (Cursor**)&p->azVar[nVar];
p->nCursor = nCursor;
for(n=0; n<nVar; n++){
p->aVar[n].flags = MEM_Null;
p->aVar[n].db = db;
}
for(n=1; n<=nMem; n++){
p->aMem[n].flags = MEM_Null;
p->aMem[n].db = db;
}
}
}
#ifdef SQLITE_DEBUG
for(n=1; n<p->nMem; n++){
assert( p->aMem[n].db==db );
}
#endif
p->pc = -1;
p->rc = SQLITE_OK;
p->uniqueCnt = 0;
p->errorAction = OE_Abort;
p->explain |= isExplain;
p->magic = VDBE_MAGIC_RUN;
p->nChange = 0;
p->cacheCtr = 1;
p->minWriteFileFormat = 255;
p->openedStatement = 0;
#ifdef VDBE_PROFILE
{
int i;
for(i=0; i<p->nOp; i++){
p->aOp[i].cnt = 0;
p->aOp[i].cycles = 0;
}
}
#endif
}
/*
** Close a VDBE cursor and release all the resources that cursor
** happens to hold.
*/
SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *p, Cursor *pCx){
if( pCx==0 ){
return;
}
if( pCx->pBt ){
sqlite3BtreeClose(pCx->pBt);
/* The pCx->pCursor will be close automatically, if it exists, by
** the call above. */
}else if( pCx->pCursor ){
sqlite3BtreeCloseCursor(pCx->pCursor);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pCx->pVtabCursor ){
sqlite3_vtab_cursor *pVtabCursor = pCx->pVtabCursor;
const sqlite3_module *pModule = pCx->pModule;
p->inVtabMethod = 1;
(void)sqlite3SafetyOff(p->db);
pModule->xClose(pVtabCursor);
(void)sqlite3SafetyOn(p->db);
p->inVtabMethod = 0;
}
#endif
if( !pCx->ephemPseudoTable ){
sqlite3DbFree(p->db, pCx->pData);
}
}
/*
** Close all cursors except for VTab cursors that are currently
** in use.
*/
static void closeAllCursorsExceptActiveVtabs(Vdbe *p){
int i;
if( p->apCsr==0 ) return;
for(i=0; i<p->nCursor; i++){
Cursor *pC = p->apCsr[i];
if( pC && (!p->inVtabMethod || !pC->pVtabCursor) ){
sqlite3VdbeFreeCursor(p, pC);
p->apCsr[i] = 0;
}
}
}
/*
** Clean up the VM after execution.
**
** This routine will automatically close any cursors, lists, and/or
** sorters that were left open. It also deletes the values of
** variables in the aVar[] array.
*/
static void Cleanup(Vdbe *p){
int i;
sqlite3 *db = p->db;
closeAllCursorsExceptActiveVtabs(p);
for(i=1; i<=p->nMem; i++){
MemSetTypeFlag(&p->aMem[i], MEM_Null);
}
releaseMemArray(&p->aMem[1], p->nMem);
sqlite3VdbeFifoClear(&p->sFifo);
if( p->contextStack ){
for(i=0; i<p->contextStackTop; i++){
sqlite3VdbeFifoClear(&p->contextStack[i].sFifo);
}
sqlite3DbFree(db, p->contextStack);
}
p->contextStack = 0;
p->contextStackDepth = 0;
p->contextStackTop = 0;
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = 0;
p->pResultSet = 0;
}
/*
** Set the number of result columns that will be returned by this SQL
** statement. This is now set at compile time, rather than during
** execution of the vdbe program so that sqlite3_column_count() can
** be called on an SQL statement before sqlite3_step().
*/
SQLITE_PRIVATE void sqlite3VdbeSetNumCols(Vdbe *p, int nResColumn){
Mem *pColName;
int n;
sqlite3 *db = p->db;
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqlite3DbFree(db, p->aColName);
n = nResColumn*COLNAME_N;
p->nResColumn = nResColumn;
p->aColName = pColName = (Mem*)sqlite3DbMallocZero(db, sizeof(Mem)*n );
if( p->aColName==0 ) return;
while( n-- > 0 ){
pColName->flags = MEM_Null;
pColName->db = p->db;
pColName++;
}
}
/*
** Set the name of the idx'th column to be returned by the SQL statement.
** zName must be a pointer to a nul terminated string.
**
** This call must be made after a call to sqlite3VdbeSetNumCols().
**
** If N==P4_STATIC it means that zName is a pointer to a constant static
** string and we can just copy the pointer. If it is P4_DYNAMIC, then
** the string is freed using sqlite3DbFree(db, ) when the vdbe is finished with
** it. Otherwise, N bytes of zName are copied.
sqlite-amalgamation.c view on Meta::CPAN
rc = sqlite3OsDelete(pVfs, zMaster, 1);
sqlite3DbFree(db, zMaster);
zMaster = 0;
if( rc ){
return rc;
}
/* All files and directories have already been synced, so the following
** calls to sqlite3BtreeCommitPhaseTwo() are only closing files and
** deleting or truncating journals. If something goes wrong while
** this is happening we don't really care. The integrity of the
** transaction is already guaranteed, but some stray 'cold' journals
** may be lying around. Returning an error code won't help matters.
*/
disable_simulated_io_errors();
sqlite3BeginBenignMalloc();
for(i=0; i<db->nDb; i++){
Btree *pBt = db->aDb[i].pBt;
if( pBt ){
sqlite3BtreeCommitPhaseTwo(pBt);
}
}
sqlite3EndBenignMalloc();
enable_simulated_io_errors();
sqlite3VtabCommit(db);
}
#endif
return rc;
}
/*
** This routine checks that the sqlite3.activeVdbeCnt count variable
** matches the number of vdbe's in the list sqlite3.pVdbe that are
** currently active. An assertion fails if the two counts do not match.
** This is an internal self-check only - it is not an essential processing
** step.
**
** This is a no-op if NDEBUG is defined.
*/
#ifndef NDEBUG
static void checkActiveVdbeCnt(sqlite3 *db){
Vdbe *p;
int cnt = 0;
p = db->pVdbe;
while( p ){
if( p->magic==VDBE_MAGIC_RUN && p->pc>=0 ){
cnt++;
}
p = p->pNext;
}
assert( cnt==db->activeVdbeCnt );
}
#else
#define checkActiveVdbeCnt(x)
#endif
/*
** For every Btree that in database connection db which
** has been modified, "trip" or invalidate each cursor in
** that Btree might have been modified so that the cursor
** can never be used again. This happens when a rollback
*** occurs. We have to trip all the other cursors, even
** cursor from other VMs in different database connections,
** so that none of them try to use the data at which they
** were pointing and which now may have been changed due
** to the rollback.
**
** Remember that a rollback can delete tables complete and
** reorder rootpages. So it is not sufficient just to save
** the state of the cursor. We have to invalidate the cursor
** so that it is never used again.
*/
static void invalidateCursorsOnModifiedBtrees(sqlite3 *db){
int i;
for(i=0; i<db->nDb; i++){
Btree *p = db->aDb[i].pBt;
if( p && sqlite3BtreeIsInTrans(p) ){
sqlite3BtreeTripAllCursors(p, SQLITE_ABORT);
}
}
}
/*
** This routine is called the when a VDBE tries to halt. If the VDBE
** has made changes and is in autocommit mode, then commit those
** changes. If a rollback is needed, then do the rollback.
**
** This routine is the only way to move the state of a VM from
** SQLITE_MAGIC_RUN to SQLITE_MAGIC_HALT. It is harmless to
** call this on a VM that is in the SQLITE_MAGIC_HALT state.
**
** Return an error code. If the commit could not complete because of
** lock contention, return SQLITE_BUSY. If SQLITE_BUSY is returned, it
** means the close did not happen and needs to be repeated.
*/
SQLITE_PRIVATE int sqlite3VdbeHalt(Vdbe *p){
sqlite3 *db = p->db;
int i;
int (*xFunc)(Btree *pBt) = 0; /* Function to call on each btree backend */
int isSpecialError; /* Set to true if SQLITE_NOMEM or IOERR */
/* This function contains the logic that determines if a statement or
** transaction will be committed or rolled back as a result of the
** execution of this virtual machine.
**
** If any of the following errors occur:
**
** SQLITE_NOMEM
** SQLITE_IOERR
** SQLITE_FULL
** SQLITE_INTERRUPT
**
** Then the internal cache might have been left in an inconsistent
** state. We need to rollback the statement transaction, if there is
** one, or the complete transaction if there is no statement transaction.
*/
if( p->db->mallocFailed ){
p->rc = SQLITE_NOMEM;
}
closeAllCursorsExceptActiveVtabs(p);
if( p->magic!=VDBE_MAGIC_RUN ){
return SQLITE_OK;
}
checkActiveVdbeCnt(db);
/* No commit or rollback needed if the program never started */
if( p->pc>=0 ){
int mrc; /* Primary error code from p->rc */
sqlite-amalgamation.c view on Meta::CPAN
/*
** Call the destructor for each auxdata entry in pVdbeFunc for which
** the corresponding bit in mask is clear. Auxdata entries beyond 31
** are always destroyed. To destroy all auxdata entries, call this
** routine with mask==0.
*/
SQLITE_PRIVATE void sqlite3VdbeDeleteAuxData(VdbeFunc *pVdbeFunc, int mask){
int i;
for(i=0; i<pVdbeFunc->nAux; i++){
struct AuxData *pAux = &pVdbeFunc->apAux[i];
if( (i>31 || !(mask&(1<<i))) && pAux->pAux ){
if( pAux->xDelete ){
pAux->xDelete(pAux->pAux);
}
pAux->pAux = 0;
}
}
}
/*
** Delete an entire VDBE.
*/
SQLITE_PRIVATE void sqlite3VdbeDelete(Vdbe *p){
int i;
sqlite3 *db;
if( p==0 ) return;
db = p->db;
if( p->pPrev ){
p->pPrev->pNext = p->pNext;
}else{
assert( db->pVdbe==p );
db->pVdbe = p->pNext;
}
if( p->pNext ){
p->pNext->pPrev = p->pPrev;
}
if( p->aOp ){
Op *pOp = p->aOp;
for(i=0; i<p->nOp; i++, pOp++){
freeP4(db, pOp->p4type, pOp->p4.p);
#ifdef SQLITE_DEBUG
sqlite3DbFree(db, pOp->zComment);
#endif
}
sqlite3DbFree(db, p->aOp);
}
releaseMemArray(p->aVar, p->nVar);
sqlite3DbFree(db, p->aLabel);
if( p->aMem ){
sqlite3DbFree(db, &p->aMem[1]);
}
releaseMemArray(p->aColName, p->nResColumn*COLNAME_N);
sqlite3DbFree(db, p->aColName);
sqlite3DbFree(db, p->zSql);
p->magic = VDBE_MAGIC_DEAD;
sqlite3DbFree(db, p);
}
/*
** If a MoveTo operation is pending on the given cursor, then do that
** MoveTo now. Return an error code. If no MoveTo is pending, this
** routine does nothing and returns SQLITE_OK.
*/
SQLITE_PRIVATE int sqlite3VdbeCursorMoveto(Cursor *p){
if( p->deferredMoveto ){
int res, rc;
#ifdef SQLITE_TEST
extern int sqlite3_search_count;
#endif
assert( p->isTable );
rc = sqlite3BtreeMoveto(p->pCursor, 0, 0, p->movetoTarget, 0, &res);
if( rc ) return rc;
*p->pIncrKey = 0;
p->lastRowid = keyToInt(p->movetoTarget);
p->rowidIsValid = res==0;
if( res<0 ){
rc = sqlite3BtreeNext(p->pCursor, &res);
if( rc ) return rc;
}
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
p->deferredMoveto = 0;
p->cacheStatus = CACHE_STALE;
}else if( p->pCursor ){
int hasMoved;
int rc = sqlite3BtreeCursorHasMoved(p->pCursor, &hasMoved);
if( rc ) return rc;
if( hasMoved ){
p->cacheStatus = CACHE_STALE;
p->nullRow = 1;
}
}
return SQLITE_OK;
}
/*
** The following functions:
**
** sqlite3VdbeSerialType()
** sqlite3VdbeSerialTypeLen()
** sqlite3VdbeSerialLen()
** sqlite3VdbeSerialPut()
** sqlite3VdbeSerialGet()
**
** encapsulate the code that serializes values for storage in SQLite
** data and index records. Each serialized value consists of a
** 'serial-type' and a blob of data. The serial type is an 8-byte unsigned
** integer, stored as a varint.
**
** In an SQLite index record, the serial type is stored directly before
** the blob of data that it corresponds to. In a table record, all serial
** types are stored at the start of the record, and the blobs of data at
** the end. Hence these functions allow the caller to handle the
** serial-type and data blob seperately.
**
** The following table describes the various storage classes for data:
**
** serial type bytes of data type
** -------------- --------------- ---------------
sqlite-amalgamation.c view on Meta::CPAN
rc = -rc;
}
return rc;
}
/*
** The argument is an index entry composed using the OP_MakeRecord opcode.
** The last entry in this record should be an integer (specifically
** an integer rowid). This routine returns the number of bytes in
** that integer.
*/
SQLITE_PRIVATE int sqlite3VdbeIdxRowidLen(const u8 *aKey, int nKey, int *pRowidLen){
u32 szHdr; /* Size of the header */
u32 typeRowid; /* Serial type of the rowid */
(void)getVarint32(aKey, szHdr);
if( szHdr>nKey ){
return SQLITE_CORRUPT_BKPT;
}
(void)getVarint32(&aKey[szHdr-1], typeRowid);
*pRowidLen = sqlite3VdbeSerialTypeLen(typeRowid);
return SQLITE_OK;
}
/*
** pCur points at an index entry created using the OP_MakeRecord opcode.
** Read the rowid (the last field in the record) and store it in *rowid.
** Return SQLITE_OK if everything works, or an error code otherwise.
*/
SQLITE_PRIVATE int sqlite3VdbeIdxRowid(BtCursor *pCur, i64 *rowid){
i64 nCellKey = 0;
int rc;
u32 szHdr; /* Size of the header */
u32 typeRowid; /* Serial type of the rowid */
u32 lenRowid; /* Size of the rowid */
Mem m, v;
sqlite3BtreeKeySize(pCur, &nCellKey);
if( nCellKey<=0 ){
return SQLITE_CORRUPT_BKPT;
}
m.flags = 0;
m.db = 0;
m.zMalloc = 0;
rc = sqlite3VdbeMemFromBtree(pCur, 0, nCellKey, 1, &m);
if( rc ){
return rc;
}
(void)getVarint32((u8*)m.z, szHdr);
(void)getVarint32((u8*)&m.z[szHdr-1], typeRowid);
lenRowid = sqlite3VdbeSerialTypeLen(typeRowid);
sqlite3VdbeSerialGet((u8*)&m.z[m.n-lenRowid], typeRowid, &v);
*rowid = v.u.i;
sqlite3VdbeMemRelease(&m);
return SQLITE_OK;
}
/*
** Compare the key of the index entry that cursor pC is point to against
** the key string in pKey (of length nKey). Write into *pRes a number
** that is negative, zero, or positive if pC is less than, equal to,
** or greater than pKey. Return SQLITE_OK on success.
**
** pKey is either created without a rowid or is truncated so that it
** omits the rowid at the end. The rowid at the end of the index entry
** is ignored as well.
*/
SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(
Cursor *pC, /* The cursor to compare against */
UnpackedRecord *pUnpacked,
int nKey, const u8 *pKey, /* The key to compare */
int *res /* Write the comparison result here */
){
i64 nCellKey = 0;
int rc;
BtCursor *pCur = pC->pCursor;
int lenRowid;
Mem m;
UnpackedRecord *pRec;
char zSpace[200];
sqlite3BtreeKeySize(pCur, &nCellKey);
if( nCellKey<=0 ){
*res = 0;
return SQLITE_OK;
}
m.db = 0;
m.flags = 0;
m.zMalloc = 0;
if( (rc = sqlite3VdbeMemFromBtree(pC->pCursor, 0, nCellKey, 1, &m))
|| (rc = sqlite3VdbeIdxRowidLen((u8*)m.z, m.n, &lenRowid))
){
return rc;
}
if( !pUnpacked ){
pRec = sqlite3VdbeRecordUnpack(pC->pKeyInfo, nKey, pKey,
zSpace, sizeof(zSpace));
}else{
pRec = pUnpacked;
}
if( pRec==0 ){
return SQLITE_NOMEM;
}
*res = sqlite3VdbeRecordCompare(m.n-lenRowid, m.z, pRec);
if( !pUnpacked ){
sqlite3VdbeDeleteUnpackedRecord(pRec);
}
sqlite3VdbeMemRelease(&m);
return SQLITE_OK;
}
/*
** This routine sets the value to be returned by subsequent calls to
** sqlite3_changes() on the database handle 'db'.
*/
SQLITE_PRIVATE void sqlite3VdbeSetChanges(sqlite3 *db, int nChange){
assert( sqlite3_mutex_held(db->mutex) );
db->nChange = nChange;
db->nTotalChange += nChange;
}
/*
** Set a flag in the vdbe to update the change counter when it is finalised
** or reset.
*/
SQLITE_PRIVATE void sqlite3VdbeCountChanges(Vdbe *v){
v->changeCntOn = 1;
}
sqlite-amalgamation.c view on Meta::CPAN
if( pStmt==0 ){
pNext = (sqlite3_stmt*)pDb->pVdbe;
}else{
pNext = (sqlite3_stmt*)((Vdbe*)pStmt)->pNext;
}
sqlite3_mutex_leave(pDb->mutex);
return pNext;
}
/************** End of vdbeapi.c *********************************************/
/************** Begin file vdbe.c ********************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** The code in this file implements execution method of the
** Virtual Database Engine (VDBE). A separate file ("vdbeaux.c")
** handles housekeeping details such as creating and deleting
** VDBE instances. This file is solely interested in executing
** the VDBE program.
**
** In the external interface, an "sqlite3_stmt*" is an opaque pointer
** to a VDBE.
**
** The SQL parser generates a program which is then executed by
** the VDBE to do the work of the SQL statement. VDBE programs are
** similar in form to assembly language. The program consists of
** a linear sequence of operations. Each operation has an opcode
** and 5 operands. Operands P1, P2, and P3 are integers. Operand P4
** is a null-terminated string. Operand P5 is an unsigned character.
** Few opcodes use all 5 operands.
**
** Computation results are stored on a set of registers numbered beginning
** with 1 and going up to Vdbe.nMem. Each register can store
** either an integer, a null-terminated string, a floating point
** number, or the SQL "NULL" value. An implicit conversion from one
** type to the other occurs as necessary.
**
** Most of the code in this file is taken up by the sqlite3VdbeExec()
** function which does the work of interpreting a VDBE program.
** But other routines are also provided to help in building up
** a program instruction by instruction.
**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files. The formatting
** of the code in this file is, therefore, important. See other comments
** in this file for details. If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.772 2008/08/02 15:10:09 danielk1977 Exp $
*/
/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_MoveXX, OP_Next, or OP_Prev opcodes. The test
** procedures use this information to make sure that indices are
** working correctly. This variable has no function other than to
** help verify the correct operation of the library.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_search_count = 0;
#endif
/*
** When this global variable is positive, it gets decremented once before
** each instruction in the VDBE. When reaches zero, the u1.isInterrupted
** field of the sqlite3 structure is set in order to simulate and interrupt.
**
** This facility is used for testing purposes only. It does not function
** in an ordinary build.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_interrupt_count = 0;
#endif
/*
** The next global variable is incremented each type the OP_Sort opcode
** is executed. The test procedures use this information to make sure that
** sorting is occurring or not occurring at appropriate times. This variable
** has no function other than to help verify the correct operation of the
** library.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_sort_count = 0;
#endif
/*
** The next global variable records the size of the largest MEM_Blob
** or MEM_Str that has been used by a VDBE opcode. The test procedures
** use this information to make sure that the zero-blob functionality
** is working correctly. This variable has no function other than to
** help verify the correct operation of the library.
*/
#ifdef SQLITE_TEST
SQLITE_API int sqlite3_max_blobsize = 0;
static void updateMaxBlobsize(Mem *p){
if( (p->flags & (MEM_Str|MEM_Blob))!=0 && p->n>sqlite3_max_blobsize ){
sqlite3_max_blobsize = p->n;
}
}
#endif
/*
** Test a register to see if it exceeds the current maximum blob size.
** If it does, record the new maximum blob size.
*/
#if defined(SQLITE_TEST) && !defined(SQLITE_OMIT_BUILTIN_TEST)
# define UPDATE_MAX_BLOBSIZE(P) updateMaxBlobsize(P)
#else
# define UPDATE_MAX_BLOBSIZE(P)
#endif
/*
** Release the memory associated with a register. This
sqlite-amalgamation.c view on Meta::CPAN
** knowing it.
**
** This routine converts an ephemeral string into a dynamically allocated
** string that the register itself controls. In other words, it
** converts an MEM_Ephem string into an MEM_Dyn string.
*/
#define Deephemeralize(P) \
if( ((P)->flags&MEM_Ephem)!=0 \
&& sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
/*
** Call sqlite3VdbeMemExpandBlob() on the supplied value (type Mem*)
** P if required.
*/
#define ExpandBlob(P) (((P)->flags&MEM_Zero)?sqlite3VdbeMemExpandBlob(P):0)
/*
** Argument pMem points at a register that will be passed to a
** user-defined function or returned to the user as the result of a query.
** The second argument, 'db_enc' is the text encoding used by the vdbe for
** register variables. This routine sets the pMem->enc and pMem->type
** variables used by the sqlite3_value_*() routines.
*/
#define storeTypeInfo(A,B) _storeTypeInfo(A)
static void _storeTypeInfo(Mem *pMem){
int flags = pMem->flags;
if( flags & MEM_Null ){
pMem->type = SQLITE_NULL;
}
else if( flags & MEM_Int ){
pMem->type = SQLITE_INTEGER;
}
else if( flags & MEM_Real ){
pMem->type = SQLITE_FLOAT;
}
else if( flags & MEM_Str ){
pMem->type = SQLITE_TEXT;
}else{
pMem->type = SQLITE_BLOB;
}
}
/*
** Properties of opcodes. The OPFLG_INITIALIZER macro is
** created by mkopcodeh.awk during compilation. Data is obtained
** from the comments following the "case OP_xxxx:" statements in
** this file.
*/
static unsigned char opcodeProperty[] = OPFLG_INITIALIZER;
/*
** Return true if an opcode has any of the OPFLG_xxx properties
** specified by mask.
*/
SQLITE_PRIVATE int sqlite3VdbeOpcodeHasProperty(int opcode, int mask){
assert( opcode>0 && opcode<sizeof(opcodeProperty) );
return (opcodeProperty[opcode]&mask)!=0;
}
/*
** Allocate cursor number iCur. Return a pointer to it. Return NULL
** if we run out of memory.
*/
static Cursor *allocateCursor(
Vdbe *p,
int iCur,
Op *pOp,
int iDb,
int isBtreeCursor
){
/* Find the memory cell that will be used to store the blob of memory
** required for this Cursor structure. It is convenient to use a
** vdbe memory cell to manage the memory allocation required for a
** Cursor structure for the following reasons:
**
** * Sometimes cursor numbers are used for a couple of different
** purposes in a vdbe program. The different uses might require
** different sized allocations. Memory cells provide growable
** allocations.
**
** * When using ENABLE_MEMORY_MANAGEMENT, memory cell buffers can
** be freed lazily via the sqlite3_release_memory() API. This
** minimizes the number of malloc calls made by the system.
**
** Memory cells for cursors are allocated at the top of the address
** space. Memory cell (p->nMem) corresponds to cursor 0. Space for
** cursor 1 is managed by memory cell (p->nMem-1), etc.
*/
Mem *pMem = &p->aMem[p->nMem-iCur];
int nByte;
Cursor *pCx = 0;
/* If the opcode of pOp is OP_SetNumColumns, then pOp->p2 contains
** the number of fields in the records contained in the table or
** index being opened. Use this to reserve space for the
** Cursor.aType[] array.
*/
int nField = 0;
if( pOp->opcode==OP_SetNumColumns || pOp->opcode==OP_OpenEphemeral ){
nField = pOp->p2;
}
nByte =
sizeof(Cursor) +
(isBtreeCursor?sqlite3BtreeCursorSize():0) +
2*nField*sizeof(u32);
assert( iCur<p->nCursor );
if( p->apCsr[iCur] ){
sqlite3VdbeFreeCursor(p, p->apCsr[iCur]);
p->apCsr[iCur] = 0;
}
if( SQLITE_OK==sqlite3VdbeMemGrow(pMem, nByte, 0) ){
p->apCsr[iCur] = pCx = (Cursor *)pMem->z;
memset(pMem->z, 0, nByte);
pCx->iDb = iDb;
pCx->nField = nField;
if( nField ){
pCx->aType = (u32 *)&pMem->z[sizeof(Cursor)];
}
if( isBtreeCursor ){
pCx->pCursor = (BtCursor *)&pMem->z[sizeof(Cursor)+2*nField*sizeof(u32)];
}
}
return pCx;
}
/*
** Try to convert a value into a numeric representation if we can
** do so without loss of information. In other words, if the string
** looks like a number, convert it into a number. If it does not
** look like a number, leave it alone.
*/
static void applyNumericAffinity(Mem *pRec){
if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
int realnum;
sqlite3VdbeMemNulTerminate(pRec);
if( (pRec->flags&MEM_Str)
&& sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
i64 value;
sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
if( !realnum && sqlite3Atoi64(pRec->z, &value) ){
pRec->u.i = value;
MemSetTypeFlag(pRec, MEM_Int);
}else{
sqlite3VdbeMemRealify(pRec);
}
}
sqlite-amalgamation.c view on Meta::CPAN
**
** An unconditional jump to address P2.
** The next instruction executed will be
** the one at index P2 from the beginning of
** the program.
*/
case OP_Goto: { /* jump */
CHECK_FOR_INTERRUPT;
pc = pOp->p2 - 1;
break;
}
/* Opcode: Gosub P1 P2 * * *
**
** Write the current address onto register P1
** and then jump to address P2.
*/
case OP_Gosub: { /* jump */
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
assert( (pIn1->flags & MEM_Dyn)==0 );
pIn1->flags = MEM_Int;
pIn1->u.i = pc;
REGISTER_TRACE(pOp->p1, pIn1);
pc = pOp->p2 - 1;
break;
}
/* Opcode: Return P1 * * * *
**
** Jump to the next instruction after the address in register P1.
*/
case OP_Return: { /* in1 */
assert( pIn1->flags & MEM_Int );
pc = pIn1->u.i;
break;
}
/* Opcode: Yield P1 * * * *
**
** Swap the program counter with the value in register P1.
*/
case OP_Yield: {
int pcDest;
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
assert( (pIn1->flags & MEM_Dyn)==0 );
pIn1->flags = MEM_Int;
pcDest = pIn1->u.i;
pIn1->u.i = pc;
REGISTER_TRACE(pOp->p1, pIn1);
pc = pcDest;
break;
}
/* Opcode: Halt P1 P2 * P4 *
**
** Exit immediately. All open cursors, Fifos, etc are closed
** automatically.
**
** P1 is the result code returned by sqlite3_exec(), sqlite3_reset(),
** or sqlite3_finalize(). For a normal halt, this should be SQLITE_OK (0).
** For errors, it can be some other value. If P1!=0 then P2 will determine
** whether or not to rollback the current transaction. Do not rollback
** if P2==OE_Fail. Do the rollback if P2==OE_Rollback. If P2==OE_Abort,
** then back out all changes that have occurred during this execution of the
** VDBE, but do not rollback the transaction.
**
** If P4 is not null then it is an error message string.
**
** There is an implied "Halt 0 0 0" instruction inserted at the very end of
** every program. So a jump past the last instruction of the program
** is the same as executing Halt.
*/
case OP_Halt: {
p->rc = pOp->p1;
p->pc = pc;
p->errorAction = pOp->p2;
if( pOp->p4.z ){
sqlite3SetString(&p->zErrMsg, db, "%s", pOp->p4.z);
}
rc = sqlite3VdbeHalt(p);
assert( rc==SQLITE_BUSY || rc==SQLITE_OK );
if( rc==SQLITE_BUSY ){
p->rc = rc = SQLITE_BUSY;
}else{
rc = p->rc ? SQLITE_ERROR : SQLITE_DONE;
}
goto vdbe_return;
}
/* Opcode: Integer P1 P2 * * *
**
** The 32-bit integer value P1 is written into register P2.
*/
case OP_Integer: { /* out2-prerelease */
pOut->flags = MEM_Int;
pOut->u.i = pOp->p1;
break;
}
/* Opcode: Int64 * P2 * P4 *
**
** P4 is a pointer to a 64-bit integer value.
** Write that value into register P2.
*/
case OP_Int64: { /* out2-prerelease */
assert( pOp->p4.pI64!=0 );
pOut->flags = MEM_Int;
pOut->u.i = *pOp->p4.pI64;
break;
}
/* Opcode: Real * P2 * P4 *
**
** P4 is a pointer to a 64-bit floating point value.
** Write that value into register P2.
*/
sqlite-amalgamation.c view on Meta::CPAN
** Make a copy of register P1 into register P2.
**
** This instruction makes a deep copy of the value. A duplicate
** is made of any string or blob constant. See also OP_SCopy.
*/
case OP_Copy: {
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
assert( pOut!=pIn1 );
sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
Deephemeralize(pOut);
REGISTER_TRACE(pOp->p2, pOut);
break;
}
/* Opcode: SCopy P1 P2 * * *
**
** Make a shallow copy of register P1 into register P2.
**
** This instruction makes a shallow copy of the value. If the value
** is a string or blob, then the copy is only a pointer to the
** original and hence if the original changes so will the copy.
** Worse, if the original is deallocated, the copy becomes invalid.
** Thus the program must guarantee that the original will not change
** during the lifetime of the copy. Use OP_Copy to make a complete
** copy.
*/
case OP_SCopy: {
assert( pOp->p1>0 );
assert( pOp->p1<=p->nMem );
pIn1 = &p->aMem[pOp->p1];
REGISTER_TRACE(pOp->p1, pIn1);
assert( pOp->p2>0 );
assert( pOp->p2<=p->nMem );
pOut = &p->aMem[pOp->p2];
assert( pOut!=pIn1 );
sqlite3VdbeMemShallowCopy(pOut, pIn1, MEM_Ephem);
REGISTER_TRACE(pOp->p2, pOut);
break;
}
/* Opcode: ResultRow P1 P2 * * *
**
** The registers P1 through P1+P2-1 contain a single row of
** results. This opcode causes the sqlite3_step() call to terminate
** with an SQLITE_ROW return code and it sets up the sqlite3_stmt
** structure to provide access to the top P1 values as the result
** row.
*/
case OP_ResultRow: {
Mem *pMem;
int i;
assert( p->nResColumn==pOp->p2 );
assert( pOp->p1>0 );
assert( pOp->p1+pOp->p2<=p->nMem );
/* Invalidate all ephemeral cursor row caches */
p->cacheCtr = (p->cacheCtr + 2)|1;
/* Make sure the results of the current row are \000 terminated
** and have an assigned type. The results are de-ephemeralized as
** as side effect.
*/
pMem = p->pResultSet = &p->aMem[pOp->p1];
for(i=0; i<pOp->p2; i++){
sqlite3VdbeMemNulTerminate(&pMem[i]);
storeTypeInfo(&pMem[i], encoding);
REGISTER_TRACE(pOp->p1+i, &pMem[i]);
}
if( db->mallocFailed ) goto no_mem;
/* Return SQLITE_ROW
*/
p->nCallback++;
p->pc = pc + 1;
rc = SQLITE_ROW;
goto vdbe_return;
}
/* Opcode: Concat P1 P2 P3 * *
**
** Add the text in register P1 onto the end of the text in
** register P2 and store the result in register P3.
** If either the P1 or P2 text are NULL then store NULL in P3.
**
** P3 = P2 || P1
**
** It is illegal for P1 and P3 to be the same register. Sometimes,
** if P3 is the same register as P2, the implementation is able
** to avoid a memcpy().
*/
case OP_Concat: { /* same as TK_CONCAT, in1, in2, out3 */
i64 nByte;
assert( pIn1!=pOut );
if( (pIn1->flags | pIn2->flags) & MEM_Null ){
sqlite3VdbeMemSetNull(pOut);
break;
}
ExpandBlob(pIn1);
Stringify(pIn1, encoding);
ExpandBlob(pIn2);
Stringify(pIn2, encoding);
nByte = pIn1->n + pIn2->n;
if( nByte>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
MemSetTypeFlag(pOut, MEM_Str);
if( sqlite3VdbeMemGrow(pOut, nByte+2, pOut==pIn2) ){
goto no_mem;
}
if( pOut!=pIn2 ){
memcpy(pOut->z, pIn2->z, pIn2->n);
}
memcpy(&pOut->z[pIn2->n], pIn1->z, pIn1->n);
pOut->z[nByte] = 0;
pOut->z[nByte+1] = 0;
sqlite-amalgamation.c view on Meta::CPAN
** is considered true if it is numeric and non-zero. If the value
** in P1 is NULL then take the jump if P3 is true.
*/
/* Opcode: IfNot P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is False. The value is
** is considered true if it has a numeric value of zero. If the value
** in P1 is NULL then take the jump if P3 is true.
*/
case OP_If: /* jump, in1 */
case OP_IfNot: { /* jump, in1 */
int c;
if( pIn1->flags & MEM_Null ){
c = pOp->p3;
}else{
#ifdef SQLITE_OMIT_FLOATING_POINT
c = sqlite3VdbeIntValue(pIn1);
#else
c = sqlite3VdbeRealValue(pIn1)!=0.0;
#endif
if( pOp->opcode==OP_IfNot ) c = !c;
}
if( c ){
pc = pOp->p2-1;
}
break;
}
/* Opcode: IsNull P1 P2 P3 * *
**
** Jump to P2 if the value in register P1 is NULL. If P3 is greater
** than zero, then check all values reg(P1), reg(P1+1),
** reg(P1+2), ..., reg(P1+P3-1).
*/
case OP_IsNull: { /* same as TK_ISNULL, jump, in1 */
int n = pOp->p3;
assert( pOp->p3==0 || pOp->p1>0 );
do{
if( (pIn1->flags & MEM_Null)!=0 ){
pc = pOp->p2 - 1;
break;
}
pIn1++;
}while( --n > 0 );
break;
}
/* Opcode: NotNull P1 P2 * * *
**
** Jump to P2 if the value in register P1 is not NULL.
*/
case OP_NotNull: { /* same as TK_NOTNULL, jump, in1 */
if( (pIn1->flags & MEM_Null)==0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: SetNumColumns * P2 * * *
**
** This opcode sets the number of columns for the cursor opened by the
** following instruction to P2.
**
** An OP_SetNumColumns is only useful if it occurs immediately before
** one of the following opcodes:
**
** OpenRead
** OpenWrite
** OpenPseudo
**
** If the OP_Column opcode is to be executed on a cursor, then
** this opcode must be present immediately before the opcode that
** opens the cursor.
*/
case OP_SetNumColumns: {
break;
}
/* Opcode: Column P1 P2 P3 P4 *
**
** Interpret the data that cursor P1 points to as a structure built using
** the MakeRecord instruction. (See the MakeRecord opcode for additional
** information about the format of the data.) Extract the P2-th column
** from this record. If there are less that (P2+1)
** values in the record, extract a NULL.
**
** The value extracted is stored in register P3.
**
** If the KeyAsData opcode has previously executed on this cursor, then the
** field might be extracted from the key rather than the data.
**
** If the column contains fewer than P2 fields, then extract a NULL. Or,
** if the P4 argument is a P4_MEM use the value of the P4 argument as
** the result.
*/
case OP_Column: {
u32 payloadSize; /* Number of bytes in the record */
int p1 = pOp->p1; /* P1 value of the opcode */
int p2 = pOp->p2; /* column number to retrieve */
Cursor *pC = 0; /* The VDBE cursor */
char *zRec; /* Pointer to complete record-data */
BtCursor *pCrsr; /* The BTree cursor */
u32 *aType; /* aType[i] holds the numeric type of the i-th column */
u32 *aOffset; /* aOffset[i] is offset to start of data for i-th column */
u32 nField; /* number of fields in the record */
int len; /* The length of the serialized data for the column */
int i; /* Loop counter */
char *zData; /* Part of the record being decoded */
Mem *pDest; /* Where to write the extracted value */
Mem sMem; /* For storing the record being decoded */
sMem.flags = 0;
sMem.db = 0;
sMem.zMalloc = 0;
assert( p1<p->nCursor );
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pDest = &p->aMem[pOp->p3];
MemSetTypeFlag(pDest, MEM_Null);
/* This block sets the variable payloadSize to be the total number of
** bytes in the record.
**
** zRec is set to be the complete text of the record if it is available.
** The complete record text is always available for pseudo-tables
** If the record is stored in a cursor, the complete record text
** might be available in the pC->aRow cache. Or it might not be.
** If the data is unavailable, zRec is set to NULL.
**
** We also compute the number of columns in the record. For cursors,
** the number of columns is stored in the Cursor.nField element.
*/
pC = p->apCsr[p1];
assert( pC!=0 );
#ifndef SQLITE_OMIT_VIRTUALTABLE
assert( pC->pVtabCursor==0 );
#endif
if( pC->pCursor!=0 ){
/* The record is stored in a B-Tree */
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
zRec = 0;
pCrsr = pC->pCursor;
if( pC->nullRow ){
payloadSize = 0;
}else if( pC->cacheStatus==p->cacheCtr ){
payloadSize = pC->payloadSize;
zRec = (char*)pC->aRow;
}else if( pC->isIndex ){
i64 payloadSize64;
sqlite3BtreeKeySize(pCrsr, &payloadSize64);
payloadSize = payloadSize64;
}else{
sqlite3BtreeDataSize(pCrsr, &payloadSize);
}
nField = pC->nField;
}else{
assert( pC->pseudoTable );
/* The record is the sole entry of a pseudo-table */
payloadSize = pC->nData;
zRec = pC->pData;
pC->cacheStatus = CACHE_STALE;
assert( payloadSize==0 || zRec!=0 );
nField = pC->nField;
pCrsr = 0;
}
/* If payloadSize is 0, then just store a NULL */
if( payloadSize==0 ){
assert( pDest->flags&MEM_Null );
goto op_column_out;
}
if( payloadSize>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
assert( p2<nField );
/* Read and parse the table header. Store the results of the parse
** into the record header cache fields of the cursor.
*/
aType = pC->aType;
if( pC->cacheStatus==p->cacheCtr ){
aOffset = pC->aOffset;
}else{
u8 *zIdx; /* Index into header */
u8 *zEndHdr; /* Pointer to first byte after the header */
u32 offset; /* Offset into the data */
int szHdrSz; /* Size of the header size field at start of record */
int avail; /* Number of bytes of available data */
assert(aType);
pC->aOffset = aOffset = &aType[nField];
pC->payloadSize = payloadSize;
pC->cacheStatus = p->cacheCtr;
/* Figure out how many bytes are in the header */
if( zRec ){
zData = zRec;
}else{
if( pC->isIndex ){
zData = (char*)sqlite3BtreeKeyFetch(pCrsr, &avail);
}else{
zData = (char*)sqlite3BtreeDataFetch(pCrsr, &avail);
}
/* If KeyFetch()/DataFetch() managed to get the entire payload,
** save the payload in the pC->aRow cache. That will save us from
** having to make additional calls to fetch the content portion of
** the record.
*/
if( avail>=payloadSize ){
zRec = zData;
pC->aRow = (u8*)zData;
}else{
pC->aRow = 0;
}
}
/* The following assert is true in all cases accept when
** the database file has been corrupted externally.
** assert( zRec!=0 || avail>=payloadSize || avail>=9 ); */
szHdrSz = getVarint32((u8*)zData, offset);
/* The KeyFetch() or DataFetch() above are fast and will get the entire
** record header in most cases. But they will fail to get the complete
** record header if the record header does not fit on a single page
** in the B-Tree. When that happens, use sqlite3VdbeMemFromBtree() to
** acquire the complete header text.
*/
if( !zRec && avail<offset ){
sMem.flags = 0;
sMem.db = 0;
rc = sqlite3VdbeMemFromBtree(pCrsr, 0, offset, pC->isIndex, &sMem);
if( rc!=SQLITE_OK ){
goto op_column_out;
}
zData = sMem.z;
}
zEndHdr = (u8 *)&zData[offset];
zIdx = (u8 *)&zData[szHdrSz];
sqlite-amalgamation.c view on Meta::CPAN
break;
}
/* Opcode: Transaction P1 P2 * * *
**
** Begin a transaction. The transaction ends when a Commit or Rollback
** opcode is encountered. Depending on the ON CONFLICT setting, the
** transaction might also be rolled back if an error is encountered.
**
** P1 is the index of the database file on which the transaction is
** started. Index 0 is the main database file and index 1 is the
** file used for temporary tables. Indices of 2 or more are used for
** attached databases.
**
** If P2 is non-zero, then a write-transaction is started. A RESERVED lock is
** obtained on the database file when a write-transaction is started. No
** other process can start another write transaction while this transaction is
** underway. Starting a write transaction also creates a rollback journal. A
** write transaction must be started before any changes can be made to the
** database. If P2 is 2 or greater then an EXCLUSIVE lock is also obtained
** on the file.
**
** If P2 is zero, then a read-lock is obtained on the database file.
*/
case OP_Transaction: {
int i = pOp->p1;
Btree *pBt;
assert( i>=0 && i<db->nDb );
assert( (p->btreeMask & (1<<i))!=0 );
pBt = db->aDb[i].pBt;
if( pBt ){
rc = sqlite3BtreeBeginTrans(pBt, pOp->p2);
if( rc==SQLITE_BUSY ){
p->pc = pc;
p->rc = rc = SQLITE_BUSY;
goto vdbe_return;
}
if( rc!=SQLITE_OK && rc!=SQLITE_READONLY /* && rc!=SQLITE_BUSY */ ){
goto abort_due_to_error;
}
}
break;
}
/* Opcode: ReadCookie P1 P2 P3 * *
**
** Read cookie number P3 from database P1 and write it into register P2.
** P3==0 is the schema version. P3==1 is the database format.
** P3==2 is the recommended pager cache size, and so forth. P1==0 is
** the main database file and P1==1 is the database file used to store
** temporary tables.
**
** If P1 is negative, then this is a request to read the size of a
** databases free-list. P3 must be set to 1 in this case. The actual
** database accessed is ((P1+1)*-1). For example, a P1 parameter of -1
** corresponds to database 0 ("main"), a P1 of -2 is database 1 ("temp").
**
** There must be a read-lock on the database (either a transaction
** must be started or there must be an open cursor) before
** executing this instruction.
*/
case OP_ReadCookie: { /* out2-prerelease */
int iMeta;
int iDb = pOp->p1;
int iCookie = pOp->p3;
assert( pOp->p3<SQLITE_N_BTREE_META );
if( iDb<0 ){
iDb = (-1*(iDb+1));
iCookie *= -1;
}
assert( iDb>=0 && iDb<db->nDb );
assert( db->aDb[iDb].pBt!=0 );
assert( (p->btreeMask & (1<<iDb))!=0 );
/* The indexing of meta values at the schema layer is off by one from
** the indexing in the btree layer. The btree considers meta[0] to
** be the number of free pages in the database (a read-only value)
** and meta[1] to be the schema cookie. The schema layer considers
** meta[1] to be the schema cookie. So we have to shift the index
** by one in the following statement.
*/
rc = sqlite3BtreeGetMeta(db->aDb[iDb].pBt, 1 + iCookie, (u32 *)&iMeta);
pOut->u.i = iMeta;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: SetCookie P1 P2 P3 * *
**
** Write the content of register P3 (interpreted as an integer)
** into cookie number P2 of database P1.
** P2==0 is the schema version. P2==1 is the database format.
** P2==2 is the recommended pager cache size, and so forth. P1==0 is
** the main database file and P1==1 is the database file used to store
** temporary tables.
**
** A transaction must be started before executing this opcode.
*/
case OP_SetCookie: { /* in3 */
Db *pDb;
assert( pOp->p2<SQLITE_N_BTREE_META );
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pDb = &db->aDb[pOp->p1];
assert( pDb->pBt!=0 );
sqlite3VdbeMemIntegerify(pIn3);
/* See note about index shifting on OP_ReadCookie */
rc = sqlite3BtreeUpdateMeta(pDb->pBt, 1+pOp->p2, (int)pIn3->u.i);
if( pOp->p2==0 ){
/* When the schema cookie changes, record the new cookie internally */
pDb->pSchema->schema_cookie = pIn3->u.i;
db->flags |= SQLITE_InternChanges;
}else if( pOp->p2==1 ){
/* Record changes in the file format */
pDb->pSchema->file_format = pIn3->u.i;
}
if( pOp->p1==1 ){
/* Invalidate all prepared statements whenever the TEMP database
** schema is changed. Ticket #1644 */
sqlite-amalgamation.c view on Meta::CPAN
}
break;
}
/* Opcode: VerifyCookie P1 P2 *
**
** Check the value of global database parameter number 0 (the
** schema version) and make sure it is equal to P2.
** P1 is the database number which is 0 for the main database file
** and 1 for the file holding temporary tables and some higher number
** for auxiliary databases.
**
** The cookie changes its value whenever the database schema changes.
** This operation is used to detect when that the cookie has changed
** and that the current process needs to reread the schema.
**
** Either a transaction needs to have been started or an OP_Open needs
** to be executed (to establish a read lock) before this opcode is
** invoked.
*/
case OP_VerifyCookie: {
int iMeta;
Btree *pBt;
assert( pOp->p1>=0 && pOp->p1<db->nDb );
assert( (p->btreeMask & (1<<pOp->p1))!=0 );
pBt = db->aDb[pOp->p1].pBt;
if( pBt ){
rc = sqlite3BtreeGetMeta(pBt, 1, (u32 *)&iMeta);
}else{
rc = SQLITE_OK;
iMeta = 0;
}
if( rc==SQLITE_OK && iMeta!=pOp->p2 ){
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = sqlite3DbStrDup(db, "database schema has changed");
/* If the schema-cookie from the database file matches the cookie
** stored with the in-memory representation of the schema, do
** not reload the schema from the database file.
**
** If virtual-tables are in use, this is not just an optimization.
** Often, v-tables store their data in other SQLite tables, which
** are queried from within xNext() and other v-table methods using
** prepared queries. If such a query is out-of-date, we do not want to
** discard the database schema, as the user code implementing the
** v-table would have to be ready for the sqlite3_vtab structure itself
** to be invalidated whenever sqlite3_step() is called from within
** a v-table method.
*/
if( db->aDb[pOp->p1].pSchema->schema_cookie!=iMeta ){
sqlite3ResetInternalSchema(db, pOp->p1);
}
sqlite3ExpirePreparedStatements(db);
rc = SQLITE_SCHEMA;
}
break;
}
/* Opcode: OpenRead P1 P2 P3 P4 P5
**
** Open a read-only cursor for the database table whose root page is
** P2 in a database file. The database file is determined by P3.
** P3==0 means the main database, P3==1 means the database used for
** temporary tables, and P3>1 means used the corresponding attached
** database. Give the new cursor an identifier of P1. The P1
** values need not be contiguous but all P1 values should be small integers.
** It is an error for P1 to be negative.
**
** If P5!=0 then use the content of register P2 as the root page, not
** the value of P2 itself.
**
** There will be a read lock on the database whenever there is an
** open cursor. If the database was unlocked prior to this instruction
** then a read lock is acquired as part of this instruction. A read
** lock allows other processes to read the database but prohibits
** any other process from modifying the database. The read lock is
** released when all cursors are closed. If this instruction attempts
** to get a read lock but fails, the script terminates with an
** SQLITE_BUSY error code.
**
** The P4 value is a pointer to a KeyInfo structure that defines the
** content and collating sequence of indices. P4 is NULL for cursors
** that are not pointing to indices.
**
** See also OpenWrite.
*/
/* Opcode: OpenWrite P1 P2 P3 P4 P5
**
** Open a read/write cursor named P1 on the table or index whose root
** page is P2. Or if P5!=0 use the content of register P2 to find the
** root page.
**
** The P4 value is a pointer to a KeyInfo structure that defines the
** content and collating sequence of indices. P4 is NULL for cursors
** that are not pointing to indices.
**
** This instruction works just like OpenRead except that it opens the cursor
** in read/write mode. For a given table, there can be one or more read-only
** cursors or a single read/write cursor but not both.
**
** See also OpenRead.
*/
case OP_OpenRead:
case OP_OpenWrite: {
int i = pOp->p1;
int p2 = pOp->p2;
int iDb = pOp->p3;
int wrFlag;
Btree *pX;
Cursor *pCur;
Db *pDb;
assert( iDb>=0 && iDb<db->nDb );
assert( (p->btreeMask & (1<<iDb))!=0 );
pDb = &db->aDb[iDb];
pX = pDb->pBt;
assert( pX!=0 );
if( pOp->opcode==OP_OpenWrite ){
wrFlag = 1;
if( pDb->pSchema->file_format < p->minWriteFileFormat ){
p->minWriteFileFormat = pDb->pSchema->file_format;
}
}else{
wrFlag = 0;
}
if( pOp->p5 ){
assert( p2>0 );
assert( p2<=p->nMem );
pIn2 = &p->aMem[p2];
sqlite3VdbeMemIntegerify(pIn2);
p2 = pIn2->u.i;
assert( p2>=2 );
}
assert( i>=0 );
pCur = allocateCursor(p, i, &pOp[-1], iDb, 1);
if( pCur==0 ) goto no_mem;
pCur->nullRow = 1;
rc = sqlite3BtreeCursor(pX, p2, wrFlag, pOp->p4.p, pCur->pCursor);
if( pOp->p4type==P4_KEYINFO ){
pCur->pKeyInfo = pOp->p4.pKeyInfo;
pCur->pIncrKey = &pCur->pKeyInfo->incrKey;
pCur->pKeyInfo->enc = ENC(p->db);
}else{
pCur->pKeyInfo = 0;
pCur->pIncrKey = &pCur->bogusIncrKey;
}
switch( rc ){
case SQLITE_BUSY: {
p->pc = pc;
p->rc = rc = SQLITE_BUSY;
goto vdbe_return;
}
case SQLITE_OK: {
int flags = sqlite3BtreeFlags(pCur->pCursor);
/* Sanity checking. Only the lower four bits of the flags byte should
** be used. Bit 3 (mask 0x08) is unpredictable. The lower 3 bits
** (mask 0x07) should be either 5 (intkey+leafdata for tables) or
** 2 (zerodata for indices). If these conditions are not met it can
** only mean that we are dealing with a corrupt database file
*/
if( (flags & 0xf0)!=0 || ((flags & 0x07)!=5 && (flags & 0x07)!=2) ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
pCur->isTable = (flags & BTREE_INTKEY)!=0;
pCur->isIndex = (flags & BTREE_ZERODATA)!=0;
/* If P4==0 it means we are expected to open a table. If P4!=0 then
** we expect to be opening an index. If this is not what happened,
** then the database is corrupt
*/
if( (pCur->isTable && pOp->p4type==P4_KEYINFO)
|| (pCur->isIndex && pOp->p4type!=P4_KEYINFO) ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
break;
}
case SQLITE_EMPTY: {
pCur->isTable = pOp->p4type!=P4_KEYINFO;
pCur->isIndex = !pCur->isTable;
pCur->pCursor = 0;
rc = SQLITE_OK;
break;
}
default: {
goto abort_due_to_error;
}
}
break;
}
/* Opcode: OpenEphemeral P1 P2 * P4 *
**
** Open a new cursor P1 to a transient table.
** The cursor is always opened read/write even if
** the main database is read-only. The transient or virtual
** table is deleted automatically when the cursor is closed.
**
** P2 is the number of columns in the virtual table.
** The cursor points to a BTree table if P4==0 and to a BTree index
** if P4 is not 0. If P4 is not NULL, it points to a KeyInfo structure
** that defines the format of keys in the index.
**
** This opcode was once called OpenTemp. But that created
** confusion because the term "temp table", might refer either
** to a TEMP table at the SQL level, or to a table opened by
** this opcode. Then this opcode was call OpenVirtual. But
** that created confusion with the whole virtual-table idea.
*/
case OP_OpenEphemeral: {
int i = pOp->p1;
Cursor *pCx;
static const int openFlags =
SQLITE_OPEN_READWRITE |
SQLITE_OPEN_CREATE |
SQLITE_OPEN_EXCLUSIVE |
SQLITE_OPEN_DELETEONCLOSE |
SQLITE_OPEN_TRANSIENT_DB;
assert( i>=0 );
pCx = allocateCursor(p, i, pOp, -1, 1);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
rc = sqlite3BtreeFactory(db, 0, 1, SQLITE_DEFAULT_TEMP_CACHE_SIZE, openFlags,
&pCx->pBt);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeBeginTrans(pCx->pBt, 1);
}
if( rc==SQLITE_OK ){
/* If a transient index is required, create it by calling
** sqlite3BtreeCreateTable() with the BTREE_ZERODATA flag before
** opening it. If a transient table is required, just use the
** automatically created table with root-page 1 (an INTKEY table).
*/
if( pOp->p4.pKeyInfo ){
int pgno;
assert( pOp->p4type==P4_KEYINFO );
rc = sqlite3BtreeCreateTable(pCx->pBt, &pgno, BTREE_ZERODATA);
if( rc==SQLITE_OK ){
assert( pgno==MASTER_ROOT+1 );
rc = sqlite3BtreeCursor(pCx->pBt, pgno, 1,
(KeyInfo*)pOp->p4.z, pCx->pCursor);
pCx->pKeyInfo = pOp->p4.pKeyInfo;
pCx->pKeyInfo->enc = ENC(p->db);
pCx->pIncrKey = &pCx->pKeyInfo->incrKey;
}
pCx->isTable = 0;
}else{
rc = sqlite3BtreeCursor(pCx->pBt, MASTER_ROOT, 1, 0, pCx->pCursor);
pCx->isTable = 1;
pCx->pIncrKey = &pCx->bogusIncrKey;
}
}
pCx->isIndex = !pCx->isTable;
break;
}
/* Opcode: OpenPseudo P1 P2 * * *
**
** Open a new cursor that points to a fake table that contains a single
** row of data. Any attempt to write a second row of data causes the
** first row to be deleted. All data is deleted when the cursor is
** closed.
**
** A pseudo-table created by this opcode is useful for holding the
** NEW or OLD tables in a trigger. Also used to hold the a single
** row output from the sorter so that the row can be decomposed into
** individual columns using the OP_Column opcode.
**
** When OP_Insert is executed to insert a row in to the pseudo table,
** the pseudo-table cursor may or may not make it's own copy of the
** original row data. If P2 is 0, then the pseudo-table will copy the
** original row data. Otherwise, a pointer to the original memory cell
** is stored. In this case, the vdbe program must ensure that the
** memory cell containing the row data is not overwritten until the
** pseudo table is closed (or a new row is inserted into it).
*/
case OP_OpenPseudo: {
int i = pOp->p1;
Cursor *pCx;
assert( i>=0 );
pCx = allocateCursor(p, i, &pOp[-1], -1, 0);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->pseudoTable = 1;
pCx->ephemPseudoTable = pOp->p2;
pCx->pIncrKey = &pCx->bogusIncrKey;
pCx->isTable = 1;
pCx->isIndex = 0;
break;
}
/* Opcode: Close P1 * * * *
**
** Close a cursor previously opened as P1. If P1 is not
** currently open, this instruction is a no-op.
*/
case OP_Close: {
int i = pOp->p1;
assert( i>=0 && i<p->nCursor );
sqlite3VdbeFreeCursor(p, p->apCsr[i]);
p->apCsr[i] = 0;
break;
}
/* Opcode: MoveGe P1 P2 P3 P4 *
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the integer value in register P3 as a key. If cursor P1 refers
** to an SQL index, then P3 is the first in an array of P4 registers
** that are used as an unpacked index key.
**
** Reposition cursor P1 so that it points to the smallest entry that
** is greater than or equal to the key value. If there are no records
** greater than or equal to the key and P2 is not zero, then jump to P2.
**
** A special feature of this opcode (and different from the
** related OP_MoveGt, OP_MoveLt, and OP_MoveLe) is that if P2 is
** zero and P1 is an SQL table (a b-tree with integer keys) then
** the seek is deferred until it is actually needed. It might be
** the case that the cursor is never accessed. By deferring the
** seek, we avoid unnecessary seeks.
**
** See also: Found, NotFound, Distinct, MoveLt, MoveGt, MoveLe
*/
/* Opcode: MoveGt P1 P2 P3 P4 *
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the integer value in register P3 as a key. If cursor P1 refers
** to an SQL index, then P3 is the first in an array of P4 registers
** that are used as an unpacked index key.
**
** Reposition cursor P1 so that it points to the smallest entry that
** is greater than the key value. If there are no records greater than
** the key and P2 is not zero, then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveLt, MoveGe, MoveLe
*/
/* Opcode: MoveLt P1 P2 P3 P4 *
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the integer value in register P3 as a key. If cursor P1 refers
** to an SQL index, then P3 is the first in an array of P4 registers
** that are used as an unpacked index key.
**
** Reposition cursor P1 so that it points to the largest entry that
** is less than the key value. If there are no records less than
** the key and P2 is not zero, then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLe
*/
/* Opcode: MoveLe P1 P2 P3 P4 *
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the integer value in register P3 as a key. If cursor P1 refers
** to an SQL index, then P3 is the first in an array of P4 registers
** that are used as an unpacked index key.
**
** Reposition cursor P1 so that it points to the largest entry that
** is less than or equal to the key value. If there are no records
** less than or equal to the key and P2 is not zero, then jump to P2.
**
** See also: Found, NotFound, Distinct, MoveGt, MoveGe, MoveLt
*/
case OP_MoveLt: /* jump, in3 */
case OP_MoveLe: /* jump, in3 */
case OP_MoveGe: /* jump, in3 */
case OP_MoveGt: { /* jump, in3 */
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
if( pC->pCursor!=0 ){
int res, oc;
oc = pOp->opcode;
pC->nullRow = 0;
*pC->pIncrKey = oc==OP_MoveGt || oc==OP_MoveLe;
if( pC->isTable ){
i64 iKey = sqlite3VdbeIntValue(pIn3);
if( pOp->p2==0 ){
assert( pOp->opcode==OP_MoveGe );
pC->movetoTarget = iKey;
pC->rowidIsValid = 0;
pC->deferredMoveto = 1;
break;
}
rc = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)iKey, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
pC->lastRowid = iKey;
pC->rowidIsValid = res==0;
}else{
UnpackedRecord r;
int nField = pOp->p4.i;
assert( pOp->p4type==P4_INT32 );
assert( nField>0 );
r.pKeyInfo = pC->pKeyInfo;
r.nField = nField;
r.needFree = 0;
r.needDestroy = 0;
r.aMem = &p->aMem[pOp->p3];
rc = sqlite3BtreeMoveto(pC->pCursor, 0, &r, 0, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
pC->rowidIsValid = 0;
}
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
*pC->pIncrKey = 0;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
if( oc==OP_MoveGe || oc==OP_MoveGt ){
if( res<0 ){
rc = sqlite3BtreeNext(pC->pCursor, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
pC->rowidIsValid = 0;
}else{
res = 0;
}
}else{
assert( oc==OP_MoveLt || oc==OP_MoveLe );
if( res>=0 ){
rc = sqlite3BtreePrevious(pC->pCursor, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
pC->rowidIsValid = 0;
}else{
/* res might be negative because the table is empty. Check to
** see if this is the case.
*/
res = sqlite3BtreeEof(pC->pCursor);
}
}
assert( pOp->p2>0 );
if( res ){
pc = pOp->p2 - 1;
}
}else if( !pC->pseudoTable ){
/* This happens when attempting to open the sqlite3_master table
** for read access returns SQLITE_EMPTY. In this case always
** take the jump (since there are no records in the table).
*/
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: Found P1 P2 P3 * *
**
** Register P3 holds a blob constructed by MakeRecord. P1 is an index.
** If an entry that matches the value in register p3 exists in P1 then
** jump to P2. If the P3 value does not match any entry in P1
** then fall thru. The P1 cursor is left pointing at the matching entry
** if it exists.
**
** This instruction is used to implement the IN operator where the
** left-hand side is a SELECT statement. P1 may be a true index, or it
** may be a temporary index that holds the results of the SELECT
** statement. This instruction is also used to implement the
** DISTINCT keyword in SELECT statements.
**
** This instruction checks if index P1 contains a record for which
** the first N serialized values exactly match the N serialized values
** in the record in register P3, where N is the total number of values in
** the P3 record (the P3 record is a prefix of the P1 record).
**
** See also: NotFound, MoveTo, IsUnique, NotExists
*/
/* Opcode: NotFound P1 P2 P3 * *
**
** Register P3 holds a blob constructed by MakeRecord. P1 is
** an index. If no entry exists in P1 that matches the blob then jump
** to P2. If an entry does existing, fall through. The cursor is left
** pointing to the entry that matches.
**
** See also: Found, MoveTo, NotExists, IsUnique
*/
case OP_NotFound: /* jump, in3 */
case OP_Found: { /* jump, in3 */
int i = pOp->p1;
int alreadyExists = 0;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor!=0 ){
int res;
assert( pC->isTable==0 );
assert( pIn3->flags & MEM_Blob );
if( pOp->opcode==OP_Found ){
pC->pKeyInfo->prefixIsEqual = 1;
}
rc = sqlite3BtreeMoveto(pC->pCursor, pIn3->z, 0, pIn3->n, 0, &res);
pC->pKeyInfo->prefixIsEqual = 0;
if( rc!=SQLITE_OK ){
break;
}
alreadyExists = (res==0);
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}
if( pOp->opcode==OP_Found ){
if( alreadyExists ) pc = pOp->p2 - 1;
}else{
if( !alreadyExists ) pc = pOp->p2 - 1;
}
break;
}
/* Opcode: IsUnique P1 P2 P3 P4 *
**
** The P3 register contains an integer record number. Call this
** record number R. The P4 register contains an index key created
** using MakeIdxRec. Call it K.
**
** P1 is an index. So it has no data and its key consists of a
** record generated by OP_MakeRecord where the last field is the
** rowid of the entry that the index refers to.
**
** This instruction asks if there is an entry in P1 where the
** fields matches K but the rowid is different from R.
** If there is no such entry, then there is an immediate
** jump to P2. If any entry does exist where the index string
** matches K but the record number is not R, then the record
** number for that entry is written into P3 and control
** falls through to the next instruction.
**
** See also: NotFound, NotExists, Found
*/
case OP_IsUnique: { /* jump, in3 */
int i = pOp->p1;
Cursor *pCx;
BtCursor *pCrsr;
Mem *pK;
sqlite-amalgamation.c view on Meta::CPAN
** record passed as an argument corrupt. Since the record in this case
** has just been created by an OP_MakeRecord instruction, and not loaded
** from the database file, it is not possible for it to be corrupt.
** Therefore, assert(rc==SQLITE_OK).
*/
rc = sqlite3VdbeIdxRowidLen((u8*)zKey, nKey, &szRowid);
assert(rc==SQLITE_OK);
len = nKey-szRowid;
/* Search for an entry in P1 where all but the last four bytes match K.
** If there is no such entry, jump immediately to P2.
*/
assert( pCx->deferredMoveto==0 );
pCx->cacheStatus = CACHE_STALE;
rc = sqlite3BtreeMoveto(pCrsr, zKey, 0, len, 0, &res);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
if( res<0 ){
rc = sqlite3BtreeNext(pCrsr, &res);
if( res ){
pc = pOp->p2 - 1;
break;
}
}
rc = sqlite3VdbeIdxKeyCompare(pCx, 0, len, (u8*)zKey, &res);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
if( res>0 ){
pc = pOp->p2 - 1;
break;
}
/* At this point, pCrsr is pointing to an entry in P1 where all but
** the final entry (the rowid) matches K. Check to see if the
** final rowid column is different from R. If it equals R then jump
** immediately to P2.
*/
rc = sqlite3VdbeIdxRowid(pCrsr, &v);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
if( v==R ){
pc = pOp->p2 - 1;
break;
}
/* The final varint of the key is different from R. Store it back
** into register R3. (The record number of an entry that violates
** a UNIQUE constraint.)
*/
pIn3->u.i = v;
assert( pIn3->flags&MEM_Int );
}
break;
}
/* Opcode: NotExists P1 P2 P3 * *
**
** Use the content of register P3 as a integer key. If a record
** with that key does not exist in table of P1, then jump to P2.
** If the record does exist, then fall thru. The cursor is left
** pointing to the record if it exists.
**
** The difference between this operation and NotFound is that this
** operation assumes the key is an integer and that P1 is a table whereas
** NotFound assumes key is a blob constructed from MakeRecord and
** P1 is an index.
**
** See also: Found, MoveTo, NotFound, IsUnique
*/
case OP_NotExists: { /* jump, in3 */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
int res;
u64 iKey;
assert( pIn3->flags & MEM_Int );
assert( p->apCsr[i]->isTable );
iKey = intToKey(pIn3->u.i);
rc = sqlite3BtreeMoveto(pCrsr, 0, 0, iKey, 0,&res);
pC->lastRowid = pIn3->u.i;
pC->rowidIsValid = res==0;
pC->nullRow = 0;
pC->cacheStatus = CACHE_STALE;
/* res might be uninitialized if rc!=SQLITE_OK. But if rc!=SQLITE_OK
** processing is about to abort so we really do not care whether or not
** the following jump is taken. (In other words, do not stress over
** the error that valgrind sometimes shows on the next statement when
** running ioerr.test and similar failure-recovery test scripts.) */
if( res!=0 ){
pc = pOp->p2 - 1;
assert( pC->rowidIsValid==0 );
}
}else if( !pC->pseudoTable ){
/* This happens when an attempt to open a read cursor on the
** sqlite_master table returns SQLITE_EMPTY.
*/
assert( pC->isTable );
pc = pOp->p2 - 1;
assert( pC->rowidIsValid==0 );
}
break;
}
/* Opcode: Sequence P1 P2 * * *
**
** Find the next available sequence number for cursor P1.
** Write the sequence number into register P2.
** The sequence number on the cursor is incremented after this
** instruction.
*/
case OP_Sequence: { /* out2-prerelease */
int i = pOp->p1;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
pOut->u.i = p->apCsr[i]->seqCount++;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: NewRowid P1 P2 P3 * *
**
** Get a new integer record number (a.k.a "rowid") used as the key to a table.
** The record number is not previously used as a key in the database
** table that cursor P1 points to. The new record number is written
** written to register P2.
**
** If P3>0 then P3 is a register that holds the largest previously
** generated record number. No new record numbers are allowed to be less
** than this value. When this value reaches its maximum, a SQLITE_FULL
** error is generated. The P3 register is updated with the generated
** record number. This P3 mechanism is used to help implement the
** AUTOINCREMENT feature.
*/
case OP_NewRowid: { /* out2-prerelease */
int i = pOp->p1;
i64 v = 0;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor==0 ){
/* The zero initialization above is all that is needed */
}else{
/* The next rowid or record number (different terms for the same
** thing) is obtained in a two-step algorithm.
**
** First we attempt to find the largest existing rowid and add one
** to that. But if the largest existing rowid is already the maximum
** positive integer, we have to fall through to the second
** probabilistic algorithm
**
** The second algorithm is to select a rowid at random and see if
** it already exists in the table. If it does not exist, we have
** succeeded. If the random rowid does exist, we select a new one
** and try again, up to 1000 times.
**
** For a table with less than 2 billion entries, the probability
** of not finding a unused rowid is about 1.0e-300. This is a
** non-zero probability, but it is still vanishingly small and should
** never cause a problem. You are much, much more likely to have a
** hardware failure than for this algorithm to fail.
**
** The analysis in the previous paragraph assumes that you have a good
** source of random numbers. Is a library function like lrand48()
** good enough? Maybe. Maybe not. It's hard to know whether there
** might be subtle bugs is some implementations of lrand48() that
** could cause problems. To avoid uncertainty, SQLite uses its own
** random number generator based on the RC4 algorithm.
**
** To promote locality of reference for repetitive inserts, the
** first few attempts at choosing a random rowid pick values just a little
** larger than the previous rowid. This has been shown experimentally
** to double the speed of the COPY operation.
*/
int res, rx=SQLITE_OK, cnt;
i64 x;
cnt = 0;
if( (sqlite3BtreeFlags(pC->pCursor)&(BTREE_INTKEY|BTREE_ZERODATA)) !=
BTREE_INTKEY ){
rc = SQLITE_CORRUPT_BKPT;
goto abort_due_to_error;
}
assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_INTKEY)!=0 );
assert( (sqlite3BtreeFlags(pC->pCursor) & BTREE_ZERODATA)==0 );
sqlite-amalgamation.c view on Meta::CPAN
#ifndef SQLITE_OMIT_AUTOINCREMENT
if( pOp->p3 ){
Mem *pMem;
assert( pOp->p3>0 && pOp->p3<=p->nMem ); /* P3 is a valid memory cell */
pMem = &p->aMem[pOp->p3];
REGISTER_TRACE(pOp->p3, pMem);
sqlite3VdbeMemIntegerify(pMem);
assert( (pMem->flags & MEM_Int)!=0 ); /* mem(P3) holds an integer */
if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){
rc = SQLITE_FULL;
goto abort_due_to_error;
}
if( v<pMem->u.i+1 ){
v = pMem->u.i + 1;
}
pMem->u.i = v;
}
#endif
if( v<MAX_ROWID ){
pC->nextRowidValid = 1;
pC->nextRowid = v+1;
}else{
pC->nextRowidValid = 0;
}
}
if( pC->useRandomRowid ){
assert( pOp->p3==0 ); /* SQLITE_FULL must have occurred prior to this */
v = db->priorNewRowid;
cnt = 0;
do{
if( cnt==0 && (v&0xffffff)==v ){
v++;
}else{
sqlite3_randomness(sizeof(v), &v);
if( cnt<5 ) v &= 0xffffff;
}
if( v==0 ) continue;
x = intToKey(v);
rx = sqlite3BtreeMoveto(pC->pCursor, 0, 0, (u64)x, 0, &res);
cnt++;
}while( cnt<100 && rx==SQLITE_OK && res==0 );
db->priorNewRowid = v;
if( rx==SQLITE_OK && res==0 ){
rc = SQLITE_FULL;
goto abort_due_to_error;
}
}
pC->rowidIsValid = 0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = v;
break;
}
/* Opcode: Insert P1 P2 P3 P4 P5
**
** Write an entry into the table of cursor P1. A new entry is
** created if it doesn't already exist or the data for an existing
** entry is overwritten. The data is the value stored register
** number P2. The key is stored in register P3. The key must
** be an integer.
**
** If the OPFLAG_NCHANGE flag of P5 is set, then the row change count is
** incremented (otherwise not). If the OPFLAG_LASTROWID flag of P5 is set,
** then rowid is stored for subsequent return by the
** sqlite3_last_insert_rowid() function (otherwise it is unmodified).
**
** Parameter P4 may point to a string containing the table-name, or
** may be NULL. If it is not NULL, then the update-hook
** (sqlite3.xUpdateCallback) is invoked following a successful insert.
**
** (WARNING/TODO: If P1 is a pseudo-cursor and P2 is dynamically
** allocated, then ownership of P2 is transferred to the pseudo-cursor
** and register P2 becomes ephemeral. If the cursor is changed, the
** value of register P2 will then change. Make sure this does not
** cause any problems.)
**
** This instruction only works on tables. The equivalent instruction
** for indices is OP_IdxInsert.
*/
case OP_Insert: {
Mem *pData = &p->aMem[pOp->p2];
Mem *pKey = &p->aMem[pOp->p3];
i64 iKey; /* The integer ROWID or key for the record to be inserted */
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
assert( pC->pCursor!=0 || pC->pseudoTable );
assert( pKey->flags & MEM_Int );
assert( pC->isTable );
REGISTER_TRACE(pOp->p2, pData);
REGISTER_TRACE(pOp->p3, pKey);
iKey = intToKey(pKey->u.i);
if( pOp->p5 & OPFLAG_NCHANGE ) p->nChange++;
if( pOp->p5 & OPFLAG_LASTROWID ) db->lastRowid = pKey->u.i;
if( pC->nextRowidValid && pKey->u.i>=pC->nextRowid ){
pC->nextRowidValid = 0;
}
if( pData->flags & MEM_Null ){
pData->z = 0;
pData->n = 0;
}else{
assert( pData->flags & (MEM_Blob|MEM_Str) );
}
if( pC->pseudoTable ){
if( !pC->ephemPseudoTable ){
sqlite3DbFree(db, pC->pData);
}
pC->iKey = iKey;
pC->nData = pData->n;
if( pData->z==pData->zMalloc || pC->ephemPseudoTable ){
pC->pData = pData->z;
if( !pC->ephemPseudoTable ){
pData->flags &= ~MEM_Dyn;
pData->flags |= MEM_Ephem;
pData->zMalloc = 0;
}
}else{
pC->pData = sqlite3Malloc( pC->nData+2 );
if( !pC->pData ) goto no_mem;
memcpy(pC->pData, pData->z, pC->nData);
pC->pData[pC->nData] = 0;
pC->pData[pC->nData+1] = 0;
}
pC->nullRow = 0;
}else{
int nZero;
if( pData->flags & MEM_Zero ){
nZero = pData->u.i;
}else{
nZero = 0;
}
rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey,
pData->z, pData->n, nZero,
pOp->p5 & OPFLAG_APPEND);
}
pC->rowidIsValid = 0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
/* Invoke the update-hook if required. */
if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
const char *zDb = db->aDb[pC->iDb].zName;
const char *zTbl = pOp->p4.z;
int op = ((pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT);
assert( pC->isTable );
db->xUpdateCallback(db->pUpdateArg, op, zDb, zTbl, iKey);
assert( pC->iDb>=0 );
}
break;
}
/* Opcode: Delete P1 P2 * P4 *
**
** Delete the record at which the P1 cursor is currently pointing.
**
** The cursor will be left pointing at either the next or the previous
** record in the table. If it is left pointing at the next record, then
** the next Next instruction will be a no-op. Hence it is OK to delete
** a record from within an Next loop.
**
** If the OPFLAG_NCHANGE flag of P2 is set, then the row change count is
** incremented (otherwise not).
**
** P1 must not be pseudo-table. It has to be a real table with
** multiple rows.
**
** If P4 is not NULL, then it is the name of the table that P1 is
** pointing to. The update hook will be invoked, if it exists.
** If P4 is not NULL then the P1 cursor must have been positioned
** using OP_NotFound prior to invoking this opcode.
*/
case OP_Delete: {
int i = pOp->p1;
i64 iKey;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
assert( pC->pCursor!=0 ); /* Only valid for real tables, no pseudotables */
/* If the update-hook will be invoked, set iKey to the rowid of the
** row being deleted.
*/
if( db->xUpdateCallback && pOp->p4.z ){
assert( pC->isTable );
assert( pC->rowidIsValid ); /* lastRowid set by previous OP_NotFound */
iKey = pC->lastRowid;
}
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
rc = sqlite3BtreeDelete(pC->pCursor);
pC->nextRowidValid = 0;
pC->cacheStatus = CACHE_STALE;
/* Invoke the update-hook if required. */
if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z ){
const char *zDb = db->aDb[pC->iDb].zName;
const char *zTbl = pOp->p4.z;
db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, zDb, zTbl, iKey);
assert( pC->iDb>=0 );
}
if( pOp->p2 & OPFLAG_NCHANGE ) p->nChange++;
break;
}
/* Opcode: ResetCount P1 * *
**
** This opcode resets the VMs internal change counter to 0. If P1 is true,
** then the value of the change counter is copied to the database handle
** change counter (returned by subsequent calls to sqlite3_changes())
** before it is reset. This is used by trigger programs.
*/
case OP_ResetCount: {
if( pOp->p1 ){
sqlite3VdbeSetChanges(db, p->nChange);
}
p->nChange = 0;
break;
}
/* Opcode: RowData P1 P2 * * *
**
** Write into register P2 the complete row data for cursor P1.
** There is no interpretation of the data.
** It is just copied onto the P2 register exactly as
** it is found in the database file.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/
/* Opcode: RowKey P1 P2 * * *
**
** Write into register P2 the complete row key for cursor P1.
** There is no interpretation of the data.
** The key is copied onto the P3 register exactly as
** it is found in the database file.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
*/
case OP_RowKey:
case OP_RowData: {
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
u32 n;
pOut = &p->aMem[pOp->p2];
/* Note that RowKey and RowData are really exactly the same instruction */
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC->isTable || pOp->opcode==OP_RowKey );
assert( pC->isIndex || pOp->opcode==OP_RowData );
assert( pC!=0 );
assert( pC->nullRow==0 );
assert( pC->pseudoTable==0 );
assert( pC->pCursor!=0 );
pCrsr = pC->pCursor;
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
if( pC->isIndex ){
i64 n64;
assert( !pC->isTable );
sqlite3BtreeKeySize(pCrsr, &n64);
if( n64>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
n = n64;
}else{
sqlite3BtreeDataSize(pCrsr, &n);
if( n>db->aLimit[SQLITE_LIMIT_LENGTH] ){
goto too_big;
}
}
if( sqlite3VdbeMemGrow(pOut, n, 0) ){
goto no_mem;
}
pOut->n = n;
MemSetTypeFlag(pOut, MEM_Blob);
if( pC->isIndex ){
rc = sqlite3BtreeKey(pCrsr, 0, n, pOut->z);
}else{
rc = sqlite3BtreeData(pCrsr, 0, n, pOut->z);
}
pOut->enc = SQLITE_UTF8; /* In case the blob is ever cast to text */
UPDATE_MAX_BLOBSIZE(pOut);
break;
}
/* Opcode: Rowid P1 P2 * * *
**
** Store in register P2 an integer which is the key of the table entry that
** P1 is currently point to.
*/
case OP_Rowid: { /* out2-prerelease */
int i = pOp->p1;
Cursor *pC;
i64 v;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
rc = sqlite3VdbeCursorMoveto(pC);
if( rc ) goto abort_due_to_error;
if( pC->rowidIsValid ){
v = pC->lastRowid;
}else if( pC->pseudoTable ){
v = keyToInt(pC->iKey);
}else if( pC->nullRow ){
/* Leave the rowid set to a NULL */
break;
}else{
assert( pC->pCursor!=0 );
sqlite3BtreeKeySize(pC->pCursor, &v);
v = keyToInt(v);
}
pOut->u.i = v;
MemSetTypeFlag(pOut, MEM_Int);
break;
}
/* Opcode: NullRow P1 * * * *
**
** Move the cursor P1 to a null row. Any OP_Column operations
** that occur while the cursor is on the null row will always
** write a NULL.
*/
case OP_NullRow: {
int i = pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
pC->nullRow = 1;
pC->rowidIsValid = 0;
break;
}
/* Opcode: Last P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1
** will refer to the last entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Last: { /* jump */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
int res;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
pCrsr = pC->pCursor;
assert( pCrsr!=0 );
rc = sqlite3BtreeLast(pCrsr, &res);
pC->nullRow = res;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
if( res && pOp->p2>0 ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: Sort P1 P2 * * *
**
** This opcode does exactly the same thing as OP_Rewind except that
** it increments an undocumented global variable used for testing.
**
** Sorting is accomplished by writing records into a sorting index,
** then rewinding that index and playing it back from beginning to
** end. We use the OP_Sort opcode instead of OP_Rewind to do the
** rewinding so that the global variable will be incremented and
** regression tests can determine whether or not the optimizer is
** correctly optimizing out sorts.
*/
case OP_Sort: { /* jump */
#ifdef SQLITE_TEST
sqlite3_sort_count++;
sqlite3_search_count--;
#endif
/* Fall through into OP_Rewind */
}
/* Opcode: Rewind P1 P2 * * *
**
** The next use of the Rowid or Column or Next instruction for P1
** will refer to the first entry in the database table or index.
** If the table or index is empty and P2>0, then jump immediately to P2.
** If P2 is 0 or if the table or index is not empty, fall through
** to the following instruction.
*/
case OP_Rewind: { /* jump */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
int res;
assert( i>=0 && i<p->nCursor );
pC = p->apCsr[i];
assert( pC!=0 );
if( (pCrsr = pC->pCursor)!=0 ){
rc = sqlite3BtreeFirst(pCrsr, &res);
pC->atFirst = res==0;
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}else{
res = 1;
}
pC->nullRow = res;
assert( pOp->p2>0 && pOp->p2<p->nOp );
if( res ){
pc = pOp->p2 - 1;
}
break;
}
/* Opcode: Next P1 P2 * * *
**
** Advance cursor P1 so that it points to the next key/data pair in its
** table or index. If there are no more key/value pairs then fall through
** to the following instruction. But if the cursor advance was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.
**
** See also: Prev
*/
/* Opcode: Prev P1 P2 * * *
**
** Back up cursor P1 so that it points to the previous key/data pair in its
** table or index. If there is no previous key/value pairs then fall through
** to the following instruction. But if the cursor backup was successful,
** jump immediately to P2.
**
** The P1 cursor must be for a real table, not a pseudo-table.
*/
case OP_Prev: /* jump */
case OP_Next: { /* jump */
Cursor *pC;
BtCursor *pCrsr;
int res;
CHECK_FOR_INTERRUPT;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pC==0 ){
break; /* See ticket #2273 */
}
pCrsr = pC->pCursor;
assert( pCrsr );
res = 1;
assert( pC->deferredMoveto==0 );
rc = pOp->opcode==OP_Next ? sqlite3BtreeNext(pCrsr, &res) :
sqlite3BtreePrevious(pCrsr, &res);
pC->nullRow = res;
pC->cacheStatus = CACHE_STALE;
if( res==0 ){
pc = pOp->p2 - 1;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
}
pC->rowidIsValid = 0;
break;
}
/* Opcode: IdxInsert P1 P2 P3 * *
**
** Register P2 holds a SQL index key made using the
** MakeIdxRec instructions. This opcode writes that key
** into the index P1. Data for the entry is nil.
**
** P3 is a flag that provides a hint to the b-tree layer that this
** insert is likely to be an append.
**
** This instruction only works for indices. The equivalent instruction
** for tables is OP_Insert.
*/
case OP_IdxInsert: { /* in2 */
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
assert( pIn2->flags & MEM_Blob );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
assert( pC->isTable==0 );
rc = ExpandBlob(pIn2);
if( rc==SQLITE_OK ){
int nKey = pIn2->n;
const char *zKey = pIn2->z;
rc = sqlite3BtreeInsert(pCrsr, zKey, nKey, "", 0, 0, pOp->p3);
assert( pC->deferredMoveto==0 );
pC->cacheStatus = CACHE_STALE;
}
}
break;
}
/* Opcode: IdxDeleteM P1 P2 P3 * *
**
** The content of P3 registers starting at register P2 form
** an unpacked index key. This opcode removes that entry from the
** index opened by cursor P1.
*/
case OP_IdxDelete: {
int i = pOp->p1;
Cursor *pC;
BtCursor *pCrsr;
assert( pOp->p3>0 );
assert( pOp->p2>0 && pOp->p2+pOp->p3<=p->nMem );
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
int res;
UnpackedRecord r;
r.pKeyInfo = pC->pKeyInfo;
r.nField = pOp->p3;
r.needFree = 0;
r.needDestroy = 0;
r.aMem = &p->aMem[pOp->p2];
rc = sqlite3BtreeMoveto(pCrsr, 0, &r, 0, 0, &res);
if( rc==SQLITE_OK && res==0 ){
rc = sqlite3BtreeDelete(pCrsr);
}
assert( pC->deferredMoveto==0 );
pC->cacheStatus = CACHE_STALE;
}
break;
}
/* Opcode: IdxRowid P1 P2 * * *
**
** Write into register P2 an integer which is the last entry in the record at
** the end of the index key pointed to by cursor P1. This integer should be
** the rowid of the table entry to which this index entry points.
**
** See also: Rowid, MakeIdxRec.
*/
case OP_IdxRowid: { /* out2-prerelease */
int i = pOp->p1;
BtCursor *pCrsr;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pCrsr = (pC = p->apCsr[i])->pCursor)!=0 ){
i64 rowid;
assert( pC->deferredMoveto==0 );
assert( pC->isTable==0 );
if( !pC->nullRow ){
rc = sqlite3VdbeIdxRowid(pCrsr, &rowid);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = rowid;
}
}
break;
}
/* Opcode: IdxGE P1 P2 P3 P4 P5
**
** The P4 register values beginning with P3 form an unpacked index
** key that omits the ROWID. Compare this key value against the index
** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
**
** If the P1 index entry is greater than or equal to the key value
** then jump to P2. Otherwise fall through to the next instruction.
**
** If P5 is non-zero then the key value is increased by an epsilon
** prior to the comparison. This make the opcode work like IdxGT except
** that if the key from register P3 is a prefix of the key in the cursor,
** the result is false whereas it would be true with IdxGT.
*/
/* Opcode: IdxLT P1 P2 P3 * P5
**
** The P4 register values beginning with P3 form an unpacked index
** key that omits the ROWID. Compare this key value against the index
** that P1 is currently pointing to, ignoring the ROWID on the P1 index.
**
** If the P1 index entry is less than the key value then jump to P2.
** Otherwise fall through to the next instruction.
**
** If P5 is non-zero then the key value is increased by an epsilon prior
** to the comparison. This makes the opcode work like IdxLE.
*/
case OP_IdxLT: /* jump, in3 */
case OP_IdxGE: { /* jump, in3 */
int i= pOp->p1;
Cursor *pC;
assert( i>=0 && i<p->nCursor );
assert( p->apCsr[i]!=0 );
if( (pC = p->apCsr[i])->pCursor!=0 ){
int res;
UnpackedRecord r;
assert( pC->deferredMoveto==0 );
assert( pOp->p5==0 || pOp->p5==1 );
assert( pOp->p4type==P4_INT32 );
r.pKeyInfo = pC->pKeyInfo;
r.nField = pOp->p4.i;
r.needFree = 0;
r.needDestroy = 0;
r.aMem = &p->aMem[pOp->p3];
*pC->pIncrKey = pOp->p5;
rc = sqlite3VdbeIdxKeyCompare(pC, &r, 0, 0, &res);
*pC->pIncrKey = 0;
if( pOp->opcode==OP_IdxLT ){
res = -res;
}else{
assert( pOp->opcode==OP_IdxGE );
res++;
}
if( res>0 ){
pc = pOp->p2 - 1 ;
}
}
break;
}
/* Opcode: Destroy P1 P2 P3 * *
**
** Delete an entire database table or index whose root page in the database
** file is given by P1.
**
** The table being destroyed is in the main database file if P3==0. If
** P3==1 then the table to be clear is in the auxiliary database file
** that is used to store tables create using CREATE TEMPORARY TABLE.
**
** If AUTOVACUUM is enabled then it is possible that another root page
** might be moved into the newly deleted root page in order to keep all
** root pages contiguous at the beginning of the database. The former
sqlite-amalgamation.c view on Meta::CPAN
if( rc==SQLITE_LOCKED ){
const char *z = pOp->p4.z;
sqlite3SetString(&p->zErrMsg, db, "database table is locked: %s", z);
}
break;
}
#endif /* SQLITE_OMIT_SHARED_CACHE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VBegin * * * P4 *
**
** P4 may be a pointer to an sqlite3_vtab structure. If so, call the
** xBegin method for that table.
**
** Also, whether or not P4 is set, check that this is not being called from
** within a callback to a virtual table xSync() method. If it is, set the
** error code to SQLITE_LOCKED.
*/
case OP_VBegin: {
sqlite3_vtab *pVtab = pOp->p4.pVtab;
rc = sqlite3VtabBegin(db, pVtab);
if( pVtab ){
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VCreate P1 * * P4 *
**
** P4 is the name of a virtual table in database P1. Call the xCreate method
** for that table.
*/
case OP_VCreate: {
rc = sqlite3VtabCallCreate(db, pOp->p1, pOp->p4.z, &p->zErrMsg);
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VDestroy P1 * * P4 *
**
** P4 is the name of a virtual table in database P1. Call the xDestroy method
** of that table.
*/
case OP_VDestroy: {
p->inVtabMethod = 2;
rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p4.z);
p->inVtabMethod = 0;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VOpen P1 * * P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** P1 is a cursor number. This opcode opens a cursor to the virtual
** table and stores that cursor in P1.
*/
case OP_VOpen: {
Cursor *pCur = 0;
sqlite3_vtab_cursor *pVtabCursor = 0;
sqlite3_vtab *pVtab = pOp->p4.pVtab;
sqlite3_module *pModule = (sqlite3_module *)pVtab->pModule;
assert(pVtab && pModule);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xOpen(pVtab, &pVtabCursor);
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( SQLITE_OK==rc ){
/* Initialize sqlite3_vtab_cursor base class */
pVtabCursor->pVtab = pVtab;
/* Initialise vdbe cursor object */
pCur = allocateCursor(p, pOp->p1, &pOp[-1], -1, 0);
if( pCur ){
pCur->pVtabCursor = pVtabCursor;
pCur->pModule = pVtabCursor->pVtab->pModule;
}else{
db->mallocFailed = 1;
pModule->xClose(pVtabCursor);
}
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VFilter P1 P2 P3 P4 *
**
** P1 is a cursor opened using VOpen. P2 is an address to jump to if
** the filtered result set is empty.
**
** P4 is either NULL or a string that was generated by the xBestIndex
** method of the module. The interpretation of the P4 string is left
** to the module implementation.
**
** This opcode invokes the xFilter method on the virtual table specified
** by P1. The integer query plan parameter to xFilter is stored in register
** P3. Register P3+1 stores the argc parameter to be passed to the
** xFilter method. Registers P3+2..P3+1+argc are the argc
** additional parameters which are passed to
** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
**
** A jump is made to P2 if the result set after filtering would be empty.
*/
case OP_VFilter: { /* jump */
int nArg;
int iQuery;
const sqlite3_module *pModule;
Mem *pQuery = &p->aMem[pOp->p3];
Mem *pArgc = &pQuery[1];
sqlite3_vtab_cursor *pVtabCursor;
sqlite3_vtab *pVtab;
Cursor *pCur = p->apCsr[pOp->p1];
REGISTER_TRACE(pOp->p3, pQuery);
assert( pCur->pVtabCursor );
pVtabCursor = pCur->pVtabCursor;
pVtab = pVtabCursor->pVtab;
pModule = pVtab->pModule;
/* Grab the index number and argc parameters */
assert( (pQuery->flags&MEM_Int)!=0 && pArgc->flags==MEM_Int );
nArg = pArgc->u.i;
iQuery = pQuery->u.i;
/* Invoke the xFilter method */
{
int res = 0;
int i;
Mem **apArg = p->apArg;
for(i = 0; i<nArg; i++){
apArg[i] = &pArgc[i+1];
storeTypeInfo(apArg[i], 0);
}
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
sqlite3VtabLock(pVtab);
p->inVtabMethod = 1;
rc = pModule->xFilter(pVtabCursor, iQuery, pOp->p4.z, nArg, apArg);
p->inVtabMethod = 0;
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
sqlite3VtabUnlock(db, pVtab);
if( rc==SQLITE_OK ){
res = pModule->xEof(pVtabCursor);
}
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( res ){
pc = pOp->p2 - 1;
}
}
pCur->nullRow = 0;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VRowid P1 P2 * * *
**
** Store into register P2 the rowid of
** the virtual-table that the P1 cursor is pointing to.
*/
case OP_VRowid: { /* out2-prerelease */
sqlite3_vtab *pVtab;
const sqlite3_module *pModule;
sqlite_int64 iRow;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
if( pCur->nullRow ){
break;
}
pVtab = pCur->pVtabCursor->pVtab;
pModule = pVtab->pModule;
assert( pModule->xRowid );
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xRowid(pCur->pVtabCursor, &iRow);
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
MemSetTypeFlag(pOut, MEM_Int);
pOut->u.i = iRow;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VColumn P1 P2 P3 * *
**
** Store the value of the P2-th column of
** the row of the virtual-table that the
** P1 cursor is pointing to into register P3.
*/
case OP_VColumn: {
sqlite3_vtab *pVtab;
const sqlite3_module *pModule;
Mem *pDest;
sqlite3_context sContext;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
assert( pOp->p3>0 && pOp->p3<=p->nMem );
pDest = &p->aMem[pOp->p3];
if( pCur->nullRow ){
sqlite3VdbeMemSetNull(pDest);
break;
}
pVtab = pCur->pVtabCursor->pVtab;
pModule = pVtab->pModule;
assert( pModule->xColumn );
memset(&sContext, 0, sizeof(sContext));
/* The output cell may already have a buffer allocated. Move
** the current contents to sContext.s so in case the user-function
** can use the already allocated buffer instead of allocating a
** new one.
*/
sqlite3VdbeMemMove(&sContext.s, pDest);
MemSetTypeFlag(&sContext.s, MEM_Null);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
rc = pModule->xColumn(pCur->pVtabCursor, &sContext, pOp->p2);
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
/* Copy the result of the function to the P3 register. We
** do this regardless of whether or not an error occured to ensure any
** dynamic allocation in sContext.s (a Mem struct) is released.
*/
sqlite3VdbeChangeEncoding(&sContext.s, encoding);
REGISTER_TRACE(pOp->p3, pDest);
sqlite3VdbeMemMove(pDest, &sContext.s);
UPDATE_MAX_BLOBSIZE(pDest);
if( sqlite3SafetyOn(db) ){
goto abort_due_to_misuse;
}
if( sqlite3VdbeMemTooBig(pDest) ){
goto too_big;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VNext P1 P2 * * *
**
** Advance virtual table P1 to the next row in its result set and
** jump to instruction P2. Or, if the virtual table has reached
** the end of its result set, then fall through to the next instruction.
*/
case OP_VNext: { /* jump */
sqlite3_vtab *pVtab;
const sqlite3_module *pModule;
int res = 0;
Cursor *pCur = p->apCsr[pOp->p1];
assert( pCur->pVtabCursor );
if( pCur->nullRow ){
break;
}
pVtab = pCur->pVtabCursor->pVtab;
pModule = pVtab->pModule;
assert( pModule->xNext );
/* Invoke the xNext() method of the module. There is no way for the
** underlying implementation to return an error if one occurs during
** xNext(). Instead, if an error occurs, true is returned (indicating that
** data is available) and the error code returned when xColumn or
** some other method is next invoked on the save virtual table cursor.
*/
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
sqlite3VtabLock(pVtab);
p->inVtabMethod = 1;
rc = pModule->xNext(pCur->pVtabCursor);
p->inVtabMethod = 0;
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
sqlite3VtabUnlock(db, pVtab);
if( rc==SQLITE_OK ){
res = pModule->xEof(pCur->pVtabCursor);
}
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
if( !res ){
/* If there is data, jump to P2 */
pc = pOp->p2 - 1;
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VRename P1 * * P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** This opcode invokes the corresponding xRename method. The value
** in register P1 is passed as the zName argument to the xRename method.
*/
case OP_VRename: {
sqlite3_vtab *pVtab = pOp->p4.pVtab;
Mem *pName = &p->aMem[pOp->p1];
assert( pVtab->pModule->xRename );
REGISTER_TRACE(pOp->p1, pName);
Stringify(pName, encoding);
if( sqlite3SafetyOff(db) ) goto abort_due_to_misuse;
sqlite3VtabLock(pVtab);
rc = pVtab->pModule->xRename(pVtab, pName->z);
sqlite3DbFree(db, p->zErrMsg);
p->zErrMsg = pVtab->zErrMsg;
pVtab->zErrMsg = 0;
sqlite3VtabUnlock(db, pVtab);
if( sqlite3SafetyOn(db) ) goto abort_due_to_misuse;
break;
}
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VUpdate P1 P2 P3 P4 *
**
** P4 is a pointer to a virtual table object, an sqlite3_vtab structure.
** This opcode invokes the corresponding xUpdate method. P2 values
** are contiguous memory cells starting at P3 to pass to the xUpdate
** invocation. The value in register (P3+P2-1) corresponds to the
** p2th element of the argv array passed to xUpdate.
**
sqlite-amalgamation.c view on Meta::CPAN
rc = SQLITE_NOMEM;
goto vdbe_error_halt;
/* Jump to here for an SQLITE_MISUSE error.
*/
abort_due_to_misuse:
rc = SQLITE_MISUSE;
/* Fall thru into abort_due_to_error */
/* Jump to here for any other kind of fatal error. The "rc" variable
** should hold the error number.
*/
abort_due_to_error:
assert( p->zErrMsg==0 );
if( db->mallocFailed ) rc = SQLITE_NOMEM;
if( rc!=SQLITE_IOERR_NOMEM ){
sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
}
goto vdbe_error_halt;
/* Jump to here if the sqlite3_interrupt() API sets the interrupt
** flag.
*/
abort_due_to_interrupt:
assert( db->u1.isInterrupted );
rc = SQLITE_INTERRUPT;
p->rc = rc;
sqlite3SetString(&p->zErrMsg, db, "%s", sqlite3ErrStr(rc));
goto vdbe_error_halt;
}
/************** End of vdbe.c ************************************************/
/************** Begin file vdbeblob.c ****************************************/
/*
** 2007 May 1
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
**
** This file contains code used to implement incremental BLOB I/O.
**
** $Id: vdbeblob.c,v 1.25 2008/07/28 19:34:54 drh Exp $
*/
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Valid sqlite3_blob* handles point to Incrblob structures.
*/
typedef struct Incrblob Incrblob;
struct Incrblob {
int flags; /* Copy of "flags" passed to sqlite3_blob_open() */
int nByte; /* Size of open blob, in bytes */
int iOffset; /* Byte offset of blob in cursor data */
BtCursor *pCsr; /* Cursor pointing at blob row */
sqlite3_stmt *pStmt; /* Statement holding cursor open */
sqlite3 *db; /* The associated database */
};
/*
** Open a blob handle.
*/
SQLITE_API int sqlite3_blob_open(
sqlite3* db, /* The database connection */
const char *zDb, /* The attached database containing the blob */
const char *zTable, /* The table containing the blob */
const char *zColumn, /* The column containing the blob */
sqlite_int64 iRow, /* The row containing the glob */
int flags, /* True -> read/write access, false -> read-only */
sqlite3_blob **ppBlob /* Handle for accessing the blob returned here */
){
int nAttempt = 0;
int iCol; /* Index of zColumn in row-record */
/* This VDBE program seeks a btree cursor to the identified
** db/table/row entry. The reason for using a vdbe program instead
** of writing code to use the b-tree layer directly is that the
** vdbe program will take advantage of the various transaction,
** locking and error handling infrastructure built into the vdbe.
**
** After seeking the cursor, the vdbe executes an OP_ResultRow.
** Code external to the Vdbe then "borrows" the b-tree cursor and
** uses it to implement the blob_read(), blob_write() and
** blob_bytes() functions.
**
** The sqlite3_blob_close() function finalizes the vdbe program,
** which closes the b-tree cursor and (possibly) commits the
** transaction.
*/
static const VdbeOpList openBlob[] = {
{OP_Transaction, 0, 0, 0}, /* 0: Start a transaction */
{OP_VerifyCookie, 0, 0, 0}, /* 1: Check the schema cookie */
/* One of the following two instructions is replaced by an
** OP_Noop before exection.
*/
{OP_SetNumColumns, 0, 0, 0}, /* 2: Num cols for cursor */
{OP_OpenRead, 0, 0, 0}, /* 3: Open cursor 0 for reading */
{OP_SetNumColumns, 0, 0, 0}, /* 4: Num cols for cursor */
{OP_OpenWrite, 0, 0, 0}, /* 5: Open cursor 0 for read/write */
{OP_Variable, 1, 1, 0}, /* 6: Push the rowid to the stack */
{OP_NotExists, 0, 10, 1}, /* 7: Seek the cursor */
{OP_Column, 0, 0, 1}, /* 8 */
{OP_ResultRow, 1, 0, 0}, /* 9 */
{OP_Close, 0, 0, 0}, /* 10 */
{OP_Halt, 0, 0, 0}, /* 11 */
};
Vdbe *v = 0;
int rc = SQLITE_OK;
char zErr[128];
zErr[0] = 0;
sqlite3_mutex_enter(db->mutex);
do {
Parse sParse;
Table *pTab;
memset(&sParse, 0, sizeof(Parse));
sParse.db = db;
if( sqlite3SafetyOn(db) ){
sqlite3_mutex_leave(db->mutex);
return SQLITE_MISUSE;
}
sqlite3BtreeEnterAll(db);
pTab = sqlite3LocateTable(&sParse, 0, zTable, zDb);
if( pTab && IsVirtual(pTab) ){
pTab = 0;
sqlite3ErrorMsg(&sParse, "cannot open virtual table: %s", zTable);
}
#ifndef SQLITE_OMIT_VIEW
if( pTab && pTab->pSelect ){
pTab = 0;
sqlite3ErrorMsg(&sParse, "cannot open view: %s", zTable);
}
#endif
if( !pTab ){
if( sParse.zErrMsg ){
sqlite3_snprintf(sizeof(zErr), zErr, "%s", sParse.zErrMsg);
}
sqlite3DbFree(db, sParse.zErrMsg);
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* Now search pTab for the exact column. */
for(iCol=0; iCol < pTab->nCol; iCol++) {
if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){
break;
}
}
if( iCol==pTab->nCol ){
sqlite3_snprintf(sizeof(zErr), zErr, "no such column: \"%s\"", zColumn);
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
/* If the value is being opened for writing, check that the
** column is not indexed. It is against the rules to open an
** indexed column for writing.
*/
if( flags ){
Index *pIdx;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int j;
for(j=0; j<pIdx->nColumn; j++){
if( pIdx->aiColumn[j]==iCol ){
sqlite3_snprintf(sizeof(zErr), zErr,
"cannot open indexed column for writing");
rc = SQLITE_ERROR;
(void)sqlite3SafetyOff(db);
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
}
}
}
v = sqlite3VdbeCreate(db);
if( v ){
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob);
/* Configure the OP_Transaction */
sqlite3VdbeChangeP1(v, 0, iDb);
sqlite3VdbeChangeP2(v, 0, (flags ? 1 : 0));
/* Configure the OP_VerifyCookie */
sqlite3VdbeChangeP1(v, 1, iDb);
sqlite3VdbeChangeP2(v, 1, pTab->pSchema->schema_cookie);
/* Make sure a mutex is held on the table to be accessed */
sqlite3VdbeUsesBtree(v, iDb);
/* Remove either the OP_OpenWrite or OpenRead. Set the P2
** parameter of the other to pTab->tnum.
*/
sqlite3VdbeChangeToNoop(v, (flags ? 3 : 5), 1);
sqlite3VdbeChangeP2(v, (flags ? 5 : 3), pTab->tnum);
sqlite3VdbeChangeP3(v, (flags ? 5 : 3), iDb);
/* Configure the OP_SetNumColumns. Configure the cursor to
** think that the table has one more column than it really
** does. An OP_Column to retrieve this imaginary column will
** always return an SQL NULL. This is useful because it means
** we can invoke OP_Column to fill in the vdbe cursors type
** and offset cache without causing any IO.
*/
sqlite3VdbeChangeP2(v, flags ? 4 : 2, pTab->nCol+1);
sqlite3VdbeChangeP2(v, 8, pTab->nCol);
if( !db->mallocFailed ){
sqlite3VdbeMakeReady(v, 1, 1, 1, 0);
}
}
sqlite3BtreeLeaveAll(db);
rc = sqlite3SafetyOff(db);
if( rc!=SQLITE_OK || db->mallocFailed ){
goto blob_open_out;
}
sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow);
rc = sqlite3_step((sqlite3_stmt *)v);
if( rc!=SQLITE_ROW ){
nAttempt++;
rc = sqlite3_finalize((sqlite3_stmt *)v);
sqlite3_snprintf(sizeof(zErr), zErr, sqlite3_errmsg(db));
v = 0;
}
} while( nAttempt<5 && rc==SQLITE_SCHEMA );
if( rc==SQLITE_ROW ){
/* The row-record has been opened successfully. Check that the
** column in question contains text or a blob. If it contains
** text, it is up to the caller to get the encoding right.
*/
Incrblob *pBlob;
u32 type = v->apCsr[0]->aType[iCol];
if( type<12 ){
sqlite3_snprintf(sizeof(zErr), zErr, "cannot open value of type %s",
type==0?"null": type==7?"real": "integer"
);
rc = SQLITE_ERROR;
goto blob_open_out;
}
pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob));
if( db->mallocFailed ){
sqlite3DbFree(db, pBlob);
goto blob_open_out;
}
pBlob->flags = flags;
pBlob->pCsr = v->apCsr[0]->pCursor;
sqlite3BtreeEnterCursor(pBlob->pCsr);
sqlite3BtreeCacheOverflow(pBlob->pCsr);
sqlite3BtreeLeaveCursor(pBlob->pCsr);
pBlob->pStmt = (sqlite3_stmt *)v;
pBlob->iOffset = v->apCsr[0]->aOffset[iCol];
pBlob->nByte = sqlite3VdbeSerialTypeLen(type);
pBlob->db = db;
*ppBlob = (sqlite3_blob *)pBlob;
rc = SQLITE_OK;
}else if( rc==SQLITE_OK ){
sqlite3_snprintf(sizeof(zErr), zErr, "no such rowid: %lld", iRow);
rc = SQLITE_ERROR;
}
sqlite-amalgamation.c view on Meta::CPAN
memcpy(pNew, p, sizeof(*pNew));
if( p->token.z!=0 ){
pNew->token.z = (u8*)sqlite3DbStrNDup(db, (char*)p->token.z, p->token.n);
pNew->token.dyn = 1;
}else{
assert( pNew->token.z==0 );
}
pNew->span.z = 0;
pNew->pLeft = sqlite3ExprDup(db, p->pLeft);
pNew->pRight = sqlite3ExprDup(db, p->pRight);
pNew->pList = sqlite3ExprListDup(db, p->pList);
pNew->pSelect = sqlite3SelectDup(db, p->pSelect);
return pNew;
}
SQLITE_PRIVATE void sqlite3TokenCopy(sqlite3 *db, Token *pTo, Token *pFrom){
if( pTo->dyn ) sqlite3DbFree(db, (char*)pTo->z);
if( pFrom->z ){
pTo->n = pFrom->n;
pTo->z = (u8*)sqlite3DbStrNDup(db, (char*)pFrom->z, pFrom->n);
pTo->dyn = 1;
}else{
pTo->z = 0;
}
}
SQLITE_PRIVATE ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p){
ExprList *pNew;
struct ExprList_item *pItem, *pOldItem;
int i;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
if( pNew==0 ) return 0;
pNew->iECursor = 0;
pNew->nExpr = pNew->nAlloc = p->nExpr;
pNew->a = pItem = sqlite3DbMallocRaw(db, p->nExpr*sizeof(p->a[0]) );
if( pItem==0 ){
sqlite3DbFree(db, pNew);
return 0;
}
pOldItem = p->a;
for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){
Expr *pNewExpr, *pOldExpr;
pItem->pExpr = pNewExpr = sqlite3ExprDup(db, pOldExpr = pOldItem->pExpr);
if( pOldExpr->span.z!=0 && pNewExpr ){
/* Always make a copy of the span for top-level expressions in the
** expression list. The logic in SELECT processing that determines
** the names of columns in the result set needs this information */
sqlite3TokenCopy(db, &pNewExpr->span, &pOldExpr->span);
}
assert( pNewExpr==0 || pNewExpr->span.z!=0
|| pOldExpr->span.z==0
|| db->mallocFailed );
pItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
pItem->sortOrder = pOldItem->sortOrder;
pItem->isAgg = pOldItem->isAgg;
pItem->done = 0;
}
return pNew;
}
/*
** If cursors, triggers, views and subqueries are all omitted from
** the build, then none of the following routines, except for
** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes
** called with a NULL argument.
*/
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \
|| !defined(SQLITE_OMIT_SUBQUERY)
SQLITE_PRIVATE SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p){
SrcList *pNew;
int i;
int nByte;
if( p==0 ) return 0;
nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0);
pNew = sqlite3DbMallocRaw(db, nByte );
if( pNew==0 ) return 0;
pNew->nSrc = pNew->nAlloc = p->nSrc;
for(i=0; i<p->nSrc; i++){
struct SrcList_item *pNewItem = &pNew->a[i];
struct SrcList_item *pOldItem = &p->a[i];
Table *pTab;
pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase);
pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias);
pNewItem->jointype = pOldItem->jointype;
pNewItem->iCursor = pOldItem->iCursor;
pNewItem->isPopulated = pOldItem->isPopulated;
pTab = pNewItem->pTab = pOldItem->pTab;
if( pTab ){
pTab->nRef++;
}
pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect);
pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn);
pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing);
pNewItem->colUsed = pOldItem->colUsed;
}
return pNew;
}
SQLITE_PRIVATE IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){
IdList *pNew;
int i;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*pNew) );
if( pNew==0 ) return 0;
pNew->nId = pNew->nAlloc = p->nId;
pNew->a = sqlite3DbMallocRaw(db, p->nId*sizeof(p->a[0]) );
if( pNew->a==0 ){
sqlite3DbFree(db, pNew);
return 0;
}
for(i=0; i<p->nId; i++){
struct IdList_item *pNewItem = &pNew->a[i];
struct IdList_item *pOldItem = &p->a[i];
pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName);
pNewItem->idx = pOldItem->idx;
}
return pNew;
}
SQLITE_PRIVATE Select *sqlite3SelectDup(sqlite3 *db, Select *p){
Select *pNew;
if( p==0 ) return 0;
pNew = sqlite3DbMallocRaw(db, sizeof(*p) );
sqlite-amalgamation.c view on Meta::CPAN
return isConst!=0;
}
/*
** If the expression p codes a constant integer that is small enough
** to fit in a 32-bit integer, return 1 and put the value of the integer
** in *pValue. If the expression is not an integer or if it is too big
** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged.
*/
SQLITE_PRIVATE int sqlite3ExprIsInteger(Expr *p, int *pValue){
int rc = 0;
if( p->flags & EP_IntValue ){
*pValue = p->iTable;
return 1;
}
switch( p->op ){
case TK_INTEGER: {
rc = sqlite3GetInt32((char*)p->token.z, pValue);
break;
}
case TK_UPLUS: {
rc = sqlite3ExprIsInteger(p->pLeft, pValue);
break;
}
case TK_UMINUS: {
int v;
if( sqlite3ExprIsInteger(p->pLeft, &v) ){
*pValue = -v;
rc = 1;
}
break;
}
default: break;
}
if( rc ){
p->op = TK_INTEGER;
p->flags |= EP_IntValue;
p->iTable = *pValue;
}
return rc;
}
/*
** Return TRUE if the given string is a row-id column name.
*/
SQLITE_PRIVATE int sqlite3IsRowid(const char *z){
if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1;
if( sqlite3StrICmp(z, "ROWID")==0 ) return 1;
if( sqlite3StrICmp(z, "OID")==0 ) return 1;
return 0;
}
/*
** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up
** that name in the set of source tables in pSrcList and make the pExpr
** expression node refer back to that source column. The following changes
** are made to pExpr:
**
** pExpr->iDb Set the index in db->aDb[] of the database holding
** the table.
** pExpr->iTable Set to the cursor number for the table obtained
** from pSrcList.
** pExpr->iColumn Set to the column number within the table.
** pExpr->op Set to TK_COLUMN.
** pExpr->pLeft Any expression this points to is deleted
** pExpr->pRight Any expression this points to is deleted.
**
** The pDbToken is the name of the database (the "X"). This value may be
** NULL meaning that name is of the form Y.Z or Z. Any available database
** can be used. The pTableToken is the name of the table (the "Y"). This
** value can be NULL if pDbToken is also NULL. If pTableToken is NULL it
** means that the form of the name is Z and that columns from any table
** can be used.
**
** If the name cannot be resolved unambiguously, leave an error message
** in pParse and return non-zero. Return zero on success.
*/
static int lookupName(
Parse *pParse, /* The parsing context */
Token *pDbToken, /* Name of the database containing table, or NULL */
Token *pTableToken, /* Name of table containing column, or NULL */
Token *pColumnToken, /* Name of the column. */
NameContext *pNC, /* The name context used to resolve the name */
Expr *pExpr /* Make this EXPR node point to the selected column */
){
char *zDb = 0; /* Name of the database. The "X" in X.Y.Z */
char *zTab = 0; /* Name of the table. The "Y" in X.Y.Z or Y.Z */
char *zCol = 0; /* Name of the column. The "Z" */
int i, j; /* Loop counters */
int cnt = 0; /* Number of matching column names */
int cntTab = 0; /* Number of matching table names */
sqlite3 *db = pParse->db; /* The database */
struct SrcList_item *pItem; /* Use for looping over pSrcList items */
struct SrcList_item *pMatch = 0; /* The matching pSrcList item */
NameContext *pTopNC = pNC; /* First namecontext in the list */
Schema *pSchema = 0; /* Schema of the expression */
assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */
zDb = sqlite3NameFromToken(db, pDbToken);
zTab = sqlite3NameFromToken(db, pTableToken);
zCol = sqlite3NameFromToken(db, pColumnToken);
if( db->mallocFailed ){
goto lookupname_end;
}
pExpr->iTable = -1;
while( pNC && cnt==0 ){
ExprList *pEList;
SrcList *pSrcList = pNC->pSrcList;
if( pSrcList ){
for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){
Table *pTab;
int iDb;
Column *pCol;
pTab = pItem->pTab;
assert( pTab!=0 );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( pTab->nCol>0 );
if( zTab ){
sqlite-amalgamation.c view on Meta::CPAN
sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId);
pNC->nErr++;
}else if( wrong_num_args ){
sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()",
nId, zId);
pNC->nErr++;
}
if( is_agg ){
pExpr->op = TK_AGG_FUNCTION;
pNC->hasAgg = 1;
}
if( is_agg ) pNC->allowAgg = 0;
for(i=0; pNC->nErr==0 && i<n; i++){
walkExprTree(pList->a[i].pExpr, nameResolverStep, pNC);
}
if( is_agg ) pNC->allowAgg = 1;
/* FIX ME: Compute pExpr->affinity based on the expected return
** type of the function
*/
return is_agg;
}
#ifndef SQLITE_OMIT_SUBQUERY
case TK_SELECT:
case TK_EXISTS:
#endif
case TK_IN: {
if( pExpr->pSelect ){
int nRef = pNC->nRef;
#ifndef SQLITE_OMIT_CHECK
if( pNC->isCheck ){
sqlite3ErrorMsg(pParse,"subqueries prohibited in CHECK constraints");
}
#endif
sqlite3SelectResolve(pParse, pExpr->pSelect, pNC);
assert( pNC->nRef>=nRef );
if( nRef!=pNC->nRef ){
ExprSetProperty(pExpr, EP_VarSelect);
}
}
break;
}
#ifndef SQLITE_OMIT_CHECK
case TK_VARIABLE: {
if( pNC->isCheck ){
sqlite3ErrorMsg(pParse,"parameters prohibited in CHECK constraints");
}
break;
}
#endif
}
return 0;
}
/*
** This routine walks an expression tree and resolves references to
** table columns. Nodes of the form ID.ID or ID resolve into an
** index to the table in the table list and a column offset. The
** Expr.opcode for such nodes is changed to TK_COLUMN. The Expr.iTable
** value is changed to the index of the referenced table in pTabList
** plus the "base" value. The base value will ultimately become the
** VDBE cursor number for a cursor that is pointing into the referenced
** table. The Expr.iColumn value is changed to the index of the column
** of the referenced table. The Expr.iColumn value for the special
** ROWID column is -1. Any INTEGER PRIMARY KEY column is tried as an
** alias for ROWID.
**
** Also resolve function names and check the functions for proper
** usage. Make sure all function names are recognized and all functions
** have the correct number of arguments. Leave an error message
** in pParse->zErrMsg if anything is amiss. Return the number of errors.
**
** If the expression contains aggregate functions then set the EP_Agg
** property on the expression.
*/
SQLITE_PRIVATE int sqlite3ExprResolveNames(
NameContext *pNC, /* Namespace to resolve expressions in. */
Expr *pExpr /* The expression to be analyzed. */
){
int savedHasAgg;
if( pExpr==0 ) return 0;
#if SQLITE_MAX_EXPR_DEPTH>0
{
if( checkExprHeight(pNC->pParse, pExpr->nHeight + pNC->pParse->nHeight) ){
return 1;
}
pNC->pParse->nHeight += pExpr->nHeight;
}
#endif
savedHasAgg = pNC->hasAgg;
pNC->hasAgg = 0;
walkExprTree(pExpr, nameResolverStep, pNC);
#if SQLITE_MAX_EXPR_DEPTH>0
pNC->pParse->nHeight -= pExpr->nHeight;
#endif
if( pNC->nErr>0 ){
ExprSetProperty(pExpr, EP_Error);
}
if( pNC->hasAgg ){
ExprSetProperty(pExpr, EP_Agg);
}else if( savedHasAgg ){
pNC->hasAgg = 1;
}
return ExprHasProperty(pExpr, EP_Error);
}
/*
** A pointer instance of this structure is used to pass information
** through walkExprTree into codeSubqueryStep().
*/
typedef struct QueryCoder QueryCoder;
struct QueryCoder {
Parse *pParse; /* The parsing context */
NameContext *pNC; /* Namespace of first enclosing query */
};
#ifdef SQLITE_TEST
int sqlite3_enable_in_opt = 1;
#else
#define sqlite3_enable_in_opt 1
#endif
/*
** Return true if the IN operator optimization is enabled and
** the SELECT statement p exists and is of the
** simple form:
**
** SELECT <column> FROM <table>
**
** If this is the case, it may be possible to use an existing table
** or index instead of generating an epheremal table.
*/
#ifndef SQLITE_OMIT_SUBQUERY
static int isCandidateForInOpt(Select *p){
SrcList *pSrc;
ExprList *pEList;
Table *pTab;
if( !sqlite3_enable_in_opt ) return 0; /* IN optimization must be enabled */
if( p==0 ) return 0; /* right-hand side of IN is SELECT */
if( p->pPrior ) return 0; /* Not a compound SELECT */
if( p->isDistinct ) return 0; /* No DISTINCT keyword */
if( p->isAgg ) return 0; /* Contains no aggregate functions */
if( p->pGroupBy ) return 0; /* Has no GROUP BY clause */
if( p->pLimit ) return 0; /* Has no LIMIT clause */
if( p->pOffset ) return 0;
if( p->pWhere ) return 0; /* Has no WHERE clause */
pSrc = p->pSrc;
if( pSrc==0 ) return 0; /* A single table in the FROM clause */
if( pSrc->nSrc!=1 ) return 0;
if( pSrc->a[0].pSelect ) return 0; /* FROM clause is not a subquery */
pTab = pSrc->a[0].pTab;
if( pTab==0 ) return 0;
if( pTab->pSelect ) return 0; /* FROM clause is not a view */
if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */
pEList = p->pEList;
if( pEList->nExpr!=1 ) return 0; /* One column in the result set */
if( pEList->a[0].pExpr->op!=TK_COLUMN ) return 0; /* Result is a column */
return 1;
}
#endif /* SQLITE_OMIT_SUBQUERY */
/*
** This function is used by the implementation of the IN (...) operator.
** It's job is to find or create a b-tree structure that may be used
** either to test for membership of the (...) set or to iterate through
** its members, skipping duplicates.
**
** The cursor opened on the structure (database table, database index
** or ephermal table) is stored in pX->iTable before this function returns.
** The returned value indicates the structure type, as follows:
**
** IN_INDEX_ROWID - The cursor was opened on a database table.
** IN_INDEX_INDEX - The cursor was opened on a database index.
** IN_INDEX_EPH - The cursor was opened on a specially created and
** populated epheremal table.
**
** An existing structure may only be used if the SELECT is of the simple
** form:
**
** SELECT <column> FROM <table>
**
** If prNotFound parameter is 0, then the structure will be used to iterate
** through the set members, skipping any duplicates. In this case an
** epheremal table must be used unless the selected <column> is guaranteed
** to be unique - either because it is an INTEGER PRIMARY KEY or it
** is unique by virtue of a constraint or implicit index.
**
** If the prNotFound parameter is not 0, then the structure will be used
** for fast set membership tests. In this case an epheremal table must
** be used unless <column> is an INTEGER PRIMARY KEY or an index can
** be found with <column> as its left-most column.
**
** When the structure is being used for set membership tests, the user
** needs to know whether or not the structure contains an SQL NULL
** value in order to correctly evaluate expressions like "X IN (Y, Z)".
** If there is a chance that the structure may contain a NULL value at
** runtime, then a register is allocated and the register number written
** to *prNotFound. If there is no chance that the structure contains a
** NULL value, then *prNotFound is left unchanged.
**
** If a register is allocated and its location stored in *prNotFound, then
** its initial value is NULL. If the structure does not remain constant
** for the duration of the query (i.e. the set is a correlated sub-select),
** the value of the allocated register is reset to NULL each time the
** structure is repopulated. This allows the caller to use vdbe code
** equivalent to the following:
**
** if( register==NULL ){
** has_null = <test if data structure contains null>
** register = 1
** }
**
** in order to avoid running the <test if data structure contains null>
** test more often than is necessary.
*/
#ifndef SQLITE_OMIT_SUBQUERY
SQLITE_PRIVATE int sqlite3FindInIndex(Parse *pParse, Expr *pX, int *prNotFound){
Select *p;
int eType = 0;
int iTab = pParse->nTab++;
int mustBeUnique = !prNotFound;
/* The follwing if(...) expression is true if the SELECT is of the
** simple form:
**
** SELECT <column> FROM <table>
**
** If this is the case, it may be possible to use an existing table
** or index instead of generating an epheremal table.
*/
p = pX->pSelect;
if( isCandidateForInOpt(p) ){
sqlite3 *db = pParse->db;
Index *pIdx;
sqlite-amalgamation.c view on Meta::CPAN
*/
static void codeReal(Vdbe *v, const char *z, int n, int negateFlag, int iMem){
assert( z || v==0 || sqlite3VdbeDb(v)->mallocFailed );
if( z ){
double value;
char *zV;
assert( !isdigit(z[n]) );
sqlite3AtoF(z, &value);
if( sqlite3IsNaN(value) ){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem);
}else{
if( negateFlag ) value = -value;
zV = dup8bytes(v, (char*)&value);
sqlite3VdbeAddOp4(v, OP_Real, 0, iMem, 0, zV, P4_REAL);
}
}
}
/*
** Generate an instruction that will put the integer describe by
** text z[0..n-1] into register iMem.
**
** The z[] string will probably not be zero-terminated. But the
** z[n] character is guaranteed to be something that does not look
** like the continuation of the number.
*/
static void codeInteger(Vdbe *v, Expr *pExpr, int negFlag, int iMem){
const char *z;
if( pExpr->flags & EP_IntValue ){
int i = pExpr->iTable;
if( negFlag ) i = -i;
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
}else if( (z = (char*)pExpr->token.z)!=0 ){
int i;
int n = pExpr->token.n;
assert( !isdigit(z[n]) );
if( sqlite3GetInt32(z, &i) ){
if( negFlag ) i = -i;
sqlite3VdbeAddOp2(v, OP_Integer, i, iMem);
}else if( sqlite3FitsIn64Bits(z, negFlag) ){
i64 value;
char *zV;
sqlite3Atoi64(z, &value);
if( negFlag ) value = -value;
zV = dup8bytes(v, (char*)&value);
sqlite3VdbeAddOp4(v, OP_Int64, 0, iMem, 0, zV, P4_INT64);
}else{
codeReal(v, z, n, negFlag, iMem);
}
}
}
/*
** Generate code that will extract the iColumn-th column from
** table pTab and store the column value in a register. An effort
** is made to store the column value in register iReg, but this is
** not guaranteed. The location of the column value is returned.
**
** There must be an open cursor to pTab in iTable when this routine
** is called. If iColumn<0 then code is generated that extracts the rowid.
**
** This routine might attempt to reuse the value of the column that
** has already been loaded into a register. The value will always
** be used if it has not undergone any affinity changes. But if
** an affinity change has occurred, then the cached value will only be
** used if allowAffChng is true.
*/
SQLITE_PRIVATE int sqlite3ExprCodeGetColumn(
Parse *pParse, /* Parsing and code generating context */
Table *pTab, /* Description of the table we are reading from */
int iColumn, /* Index of the table column */
int iTable, /* The cursor pointing to the table */
int iReg, /* Store results here */
int allowAffChng /* True if prior affinity changes are OK */
){
Vdbe *v = pParse->pVdbe;
int i;
struct yColCache *p;
for(i=0, p=pParse->aColCache; i<pParse->nColCache; i++, p++){
if( p->iTable==iTable && p->iColumn==iColumn
&& (!p->affChange || allowAffChng) ){
#if 0
sqlite3VdbeAddOp0(v, OP_Noop);
VdbeComment((v, "OPT: tab%d.col%d -> r%d", iTable, iColumn, p->iReg));
#endif
return p->iReg;
}
}
assert( v!=0 );
if( iColumn<0 ){
int op = (pTab && IsVirtual(pTab)) ? OP_VRowid : OP_Rowid;
sqlite3VdbeAddOp2(v, op, iTable, iReg);
}else if( pTab==0 ){
sqlite3VdbeAddOp3(v, OP_Column, iTable, iColumn, iReg);
}else{
int op = IsVirtual(pTab) ? OP_VColumn : OP_Column;
sqlite3VdbeAddOp3(v, op, iTable, iColumn, iReg);
sqlite3ColumnDefault(v, pTab, iColumn);
#ifndef SQLITE_OMIT_FLOATING_POINT
if( pTab->aCol[iColumn].affinity==SQLITE_AFF_REAL ){
sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg);
}
#endif
}
if( pParse->disableColCache==0 ){
i = pParse->iColCache;
p = &pParse->aColCache[i];
p->iTable = iTable;
p->iColumn = iColumn;
p->iReg = iReg;
p->affChange = 0;
i++;
if( i>=ArraySize(pParse->aColCache) ) i = 0;
if( i>pParse->nColCache ) pParse->nColCache = i;
pParse->iColCache = i;
}
return iReg;
}
/*
** Clear all column cache entries associated with the vdbe
** cursor with cursor number iTable.
*/
SQLITE_PRIVATE void sqlite3ExprClearColumnCache(Parse *pParse, int iTable){
if( iTable<0 ){
pParse->nColCache = 0;
pParse->iColCache = 0;
}else{
int i;
for(i=0; i<pParse->nColCache; i++){
if( pParse->aColCache[i].iTable==iTable ){
testcase( i==pParse->nColCache-1 );
pParse->aColCache[i] = pParse->aColCache[--pParse->nColCache];
pParse->iColCache = pParse->nColCache;
}
}
}
}
/*
** Record the fact that an affinity change has occurred on iCount
** registers starting with iStart.
*/
SQLITE_PRIVATE void sqlite3ExprCacheAffinityChange(Parse *pParse, int iStart, int iCount){
int iEnd = iStart + iCount - 1;
int i;
for(i=0; i<pParse->nColCache; i++){
int r = pParse->aColCache[i].iReg;
if( r>=iStart && r<=iEnd ){
pParse->aColCache[i].affChange = 1;
}
}
}
/*
** Generate code to move content from registers iFrom...iFrom+nReg-1
** over to iTo..iTo+nReg-1. Keep the column cache up-to-date.
*/
SQLITE_PRIVATE void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){
int i;
if( iFrom==iTo ) return;
sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg);
for(i=0; i<pParse->nColCache; i++){
int x = pParse->aColCache[i].iReg;
if( x>=iFrom && x<iFrom+nReg ){
pParse->aColCache[i].iReg += iTo-iFrom;
}
}
}
/*
** Generate code to copy content from registers iFrom...iFrom+nReg-1
** over to iTo..iTo+nReg-1.
*/
SQLITE_PRIVATE void sqlite3ExprCodeCopy(Parse *pParse, int iFrom, int iTo, int nReg){
int i;
if( iFrom==iTo ) return;
for(i=0; i<nReg; i++){
sqlite3VdbeAddOp2(pParse->pVdbe, OP_Copy, iFrom+i, iTo+i);
}
}
sqlite-amalgamation.c view on Meta::CPAN
*/
pNew = (Table*)sqlite3DbMallocZero(db, sizeof(Table));
if( !pNew ) goto exit_begin_add_column;
pParse->pNewTable = pNew;
pNew->nRef = 1;
pNew->db = db;
pNew->nCol = pTab->nCol;
assert( pNew->nCol>0 );
nAlloc = (((pNew->nCol-1)/8)*8)+8;
assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
pNew->aCol = (Column*)sqlite3DbMallocZero(db, sizeof(Column)*nAlloc);
pNew->zName = sqlite3DbStrDup(db, pTab->zName);
if( !pNew->aCol || !pNew->zName ){
db->mallocFailed = 1;
goto exit_begin_add_column;
}
memcpy(pNew->aCol, pTab->aCol, sizeof(Column)*pNew->nCol);
for(i=0; i<pNew->nCol; i++){
Column *pCol = &pNew->aCol[i];
pCol->zName = sqlite3DbStrDup(db, pCol->zName);
pCol->zColl = 0;
pCol->zType = 0;
pCol->pDflt = 0;
}
pNew->pSchema = db->aDb[iDb].pSchema;
pNew->addColOffset = pTab->addColOffset;
pNew->nRef = 1;
/* Begin a transaction and increment the schema cookie. */
sqlite3BeginWriteOperation(pParse, 0, iDb);
v = sqlite3GetVdbe(pParse);
if( !v ) goto exit_begin_add_column;
sqlite3ChangeCookie(pParse, iDb);
exit_begin_add_column:
sqlite3SrcListDelete(db, pSrc);
return;
}
#endif /* SQLITE_ALTER_TABLE */
/************** End of alter.c ***********************************************/
/************** Begin file analyze.c *****************************************/
/*
** 2005 July 8
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains code associated with the ANALYZE command.
**
** @(#) $Id: analyze.c,v 1.43 2008/07/28 19:34:53 drh Exp $
*/
#ifndef SQLITE_OMIT_ANALYZE
/*
** This routine generates code that opens the sqlite_stat1 table on cursor
** iStatCur.
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** If it does previously exist, all entires associated with table zWhere
** are removed. If zWhere==0 then all entries are removed.
*/
static void openStatTable(
Parse *pParse, /* Parsing context */
int iDb, /* The database we are looking in */
int iStatCur, /* Open the sqlite_stat1 table on this cursor */
const char *zWhere /* Delete entries associated with this table */
){
sqlite3 *db = pParse->db;
Db *pDb;
int iRootPage;
int createStat1 = 0;
Table *pStat;
Vdbe *v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
assert( sqlite3BtreeHoldsAllMutexes(db) );
assert( sqlite3VdbeDb(v)==db );
pDb = &db->aDb[iDb];
if( (pStat = sqlite3FindTable(db, "sqlite_stat1", pDb->zName))==0 ){
/* The sqlite_stat1 tables does not exist. Create it.
** Note that a side-effect of the CREATE TABLE statement is to leave
** the rootpage of the new table in register pParse->regRoot. This is
** important because the OpenWrite opcode below will be needing it. */
sqlite3NestedParse(pParse,
"CREATE TABLE %Q.sqlite_stat1(tbl,idx,stat)",
pDb->zName
);
iRootPage = pParse->regRoot;
createStat1 = 1; /* Cause rootpage to be taken from top of stack */
}else if( zWhere ){
/* The sqlite_stat1 table exists. Delete all entries associated with
** the table zWhere. */
sqlite3NestedParse(pParse,
"DELETE FROM %Q.sqlite_stat1 WHERE tbl=%Q",
pDb->zName, zWhere
);
iRootPage = pStat->tnum;
}else{
/* The sqlite_stat1 table already exists. Delete all rows. */
iRootPage = pStat->tnum;
sqlite3VdbeAddOp2(v, OP_Clear, pStat->tnum, iDb);
}
/* Open the sqlite_stat1 table for writing. Unless it was created
** by this vdbe program, lock it for writing at the shared-cache level.
** If this vdbe did create the sqlite_stat1 table, then it must have
** already obtained a schema-lock, making the write-lock redundant.
*/
if( !createStat1 ){
sqlite3TableLock(pParse, iDb, iRootPage, 1, "sqlite_stat1");
}
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 3);
sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur, iRootPage, iDb);
sqlite3VdbeChangeP5(v, createStat1);
}
/*
** Generate code to do an analysis of all indices associated with
** a single table.
*/
static void analyzeOneTable(
Parse *pParse, /* Parser context */
Table *pTab, /* Table whose indices are to be analyzed */
int iStatCur, /* Cursor that writes to the sqlite_stat1 table */
int iMem /* Available memory locations begin here */
){
Index *pIdx; /* An index to being analyzed */
int iIdxCur; /* Cursor number for index being analyzed */
int nCol; /* Number of columns in the index */
Vdbe *v; /* The virtual machine being built up */
int i; /* Loop counter */
int topOfLoop; /* The top of the loop */
int endOfLoop; /* The end of the loop */
int addr; /* The address of an instruction */
int iDb; /* Index of database containing pTab */
v = sqlite3GetVdbe(pParse);
if( v==0 || pTab==0 || pTab->pIndex==0 ){
/* Do no analysis for tables that have no indices */
return;
}
assert( sqlite3BtreeHoldsAllMutexes(pParse->db) );
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
assert( iDb>=0 );
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
pParse->db->aDb[iDb].zName ) ){
return;
}
#endif
/* Establish a read-lock on the table at the shared-cache level. */
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
iIdxCur = pParse->nTab;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
int regFields; /* Register block for building records */
int regRec; /* Register holding completed record */
int regTemp; /* Temporary use register */
int regCol; /* Content of a column from the table being analyzed */
int regRowid; /* Rowid for the inserted record */
int regF2;
/* Open a cursor to the index to be analyzed
*/
assert( iDb==sqlite3SchemaToIndex(pParse->db, pIdx->pSchema) );
nCol = pIdx->nColumn;
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, nCol+1);
sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
(char *)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
regFields = iMem+nCol*2;
regTemp = regRowid = regCol = regFields+3;
regRec = regCol+1;
if( regRec>pParse->nMem ){
pParse->nMem = regRec;
}
/* Memory cells are used as follows:
**
** mem[iMem]: The total number of rows in the table.
** mem[iMem+1]: Number of distinct values in column 1
** ...
** mem[iMem+nCol]: Number of distinct values in column N
** mem[iMem+nCol+1] Last observed value of column 1
** ...
** mem[iMem+nCol+nCol]: Last observed value of column N
**
** Cells iMem through iMem+nCol are initialized to 0. The others
** are initialized to NULL.
*/
for(i=0; i<=nCol; i++){
sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
}
/* Do the analysis.
*/
endOfLoop = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
topOfLoop = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
sqlite3VdbeAddOp3(v, OP_Ne, regCol, 0, iMem+nCol+i+1);
/**** TODO: add collating sequence *****/
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
for(i=0; i<nCol; i++){
sqlite3VdbeJumpHere(v, topOfLoop + 2*(i + 1));
sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
}
sqlite3VdbeResolveLabel(v, endOfLoop);
sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
/* Store the results.
**
** The result is a single row of the sqlite_stat1 table. The first
** two columns are the names of the table and index. The third column
sqlite-amalgamation.c view on Meta::CPAN
sqlite3DbFree(db, pTable);
}
/*
** Unlink the given table from the hash tables and the delete the
** table structure with all its indices and foreign keys.
*/
SQLITE_PRIVATE void sqlite3UnlinkAndDeleteTable(sqlite3 *db, int iDb, const char *zTabName){
Table *p;
FKey *pF1, *pF2;
Db *pDb;
assert( db!=0 );
assert( iDb>=0 && iDb<db->nDb );
assert( zTabName && zTabName[0] );
pDb = &db->aDb[iDb];
p = sqlite3HashInsert(&pDb->pSchema->tblHash, zTabName, strlen(zTabName)+1,0);
if( p ){
#ifndef SQLITE_OMIT_FOREIGN_KEY
for(pF1=p->pFKey; pF1; pF1=pF1->pNextFrom){
int nTo = strlen(pF1->zTo) + 1;
pF2 = sqlite3HashFind(&pDb->pSchema->aFKey, pF1->zTo, nTo);
if( pF2==pF1 ){
sqlite3HashInsert(&pDb->pSchema->aFKey, pF1->zTo, nTo, pF1->pNextTo);
}else{
while( pF2 && pF2->pNextTo!=pF1 ){ pF2=pF2->pNextTo; }
if( pF2 ){
pF2->pNextTo = pF1->pNextTo;
}
}
}
#endif
sqlite3DeleteTable(p);
}
db->flags |= SQLITE_InternChanges;
}
/*
** Given a token, return a string that consists of the text of that
** token with any quotations removed. Space to hold the returned string
** is obtained from sqliteMalloc() and must be freed by the calling
** function.
**
** Tokens are often just pointers into the original SQL text and so
** are not \000 terminated and are not persistent. The returned string
** is \000 terminated and is persistent.
*/
SQLITE_PRIVATE char *sqlite3NameFromToken(sqlite3 *db, Token *pName){
char *zName;
if( pName ){
zName = sqlite3DbStrNDup(db, (char*)pName->z, pName->n);
sqlite3Dequote(zName);
}else{
zName = 0;
}
return zName;
}
/*
** Open the sqlite_master table stored in database number iDb for
** writing. The table is opened using cursor 0.
*/
SQLITE_PRIVATE void sqlite3OpenMasterTable(Parse *p, int iDb){
Vdbe *v = sqlite3GetVdbe(p);
sqlite3TableLock(p, iDb, MASTER_ROOT, 1, SCHEMA_TABLE(iDb));
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, 5);/* sqlite_master has 5 columns */
sqlite3VdbeAddOp3(v, OP_OpenWrite, 0, MASTER_ROOT, iDb);
}
/*
** The token *pName contains the name of a database (either "main" or
** "temp" or the name of an attached db). This routine returns the
** index of the named database in db->aDb[], or -1 if the named db
** does not exist.
*/
SQLITE_PRIVATE int sqlite3FindDb(sqlite3 *db, Token *pName){
int i = -1; /* Database number */
int n; /* Number of characters in the name */
Db *pDb; /* A database whose name space is being searched */
char *zName; /* Name we are searching for */
zName = sqlite3NameFromToken(db, pName);
if( zName ){
n = strlen(zName);
for(i=(db->nDb-1), pDb=&db->aDb[i]; i>=0; i--, pDb--){
if( (!OMIT_TEMPDB || i!=1 ) && n==strlen(pDb->zName) &&
0==sqlite3StrICmp(pDb->zName, zName) ){
break;
}
}
sqlite3DbFree(db, zName);
}
return i;
}
/* The table or view or trigger name is passed to this routine via tokens
** pName1 and pName2. If the table name was fully qualified, for example:
**
** CREATE TABLE xxx.yyy (...);
**
** Then pName1 is set to "xxx" and pName2 "yyy". On the other hand if
** the table name is not fully qualified, i.e.:
**
** CREATE TABLE yyy(...);
**
** Then pName1 is set to "yyy" and pName2 is "".
**
** This routine sets the *ppUnqual pointer to point at the token (pName1 or
** pName2) that stores the unqualified table name. The index of the
** database "xxx" is returned.
*/
SQLITE_PRIVATE int sqlite3TwoPartName(
Parse *pParse, /* Parsing and code generating context */
Token *pName1, /* The "xxx" in the name "xxx.yyy" or "xxx" */
Token *pName2, /* The "yyy" in the name "xxx.yyy" */
Token **pUnqual /* Write the unqualified object name here */
){
int iDb; /* Database holding the object */
sqlite3 *db = pParse->db;
if( pName2 && pName2->n>0 ){
sqlite-amalgamation.c view on Meta::CPAN
}
sqlite3StartTable(pParse, pName1, pName2, isTemp, 1, 0, noErr);
p = pParse->pNewTable;
if( p==0 || pParse->nErr ){
sqlite3SelectDelete(db, pSelect);
return;
}
sqlite3TwoPartName(pParse, pName1, pName2, &pName);
iDb = sqlite3SchemaToIndex(db, p->pSchema);
if( sqlite3FixInit(&sFix, pParse, iDb, "view", pName)
&& sqlite3FixSelect(&sFix, pSelect)
){
sqlite3SelectDelete(db, pSelect);
return;
}
/* Make a copy of the entire SELECT statement that defines the view.
** This will force all the Expr.token.z values to be dynamically
** allocated rather than point to the input string - which means that
** they will persist after the current sqlite3_exec() call returns.
*/
p->pSelect = sqlite3SelectDup(db, pSelect);
sqlite3SelectDelete(db, pSelect);
if( db->mallocFailed ){
return;
}
if( !db->init.busy ){
sqlite3ViewGetColumnNames(pParse, p);
}
/* Locate the end of the CREATE VIEW statement. Make sEnd point to
** the end.
*/
sEnd = pParse->sLastToken;
if( sEnd.z[0]!=0 && sEnd.z[0]!=';' ){
sEnd.z += sEnd.n;
}
sEnd.n = 0;
n = sEnd.z - pBegin->z;
z = (const unsigned char*)pBegin->z;
while( n>0 && (z[n-1]==';' || isspace(z[n-1])) ){ n--; }
sEnd.z = &z[n-1];
sEnd.n = 1;
/* Use sqlite3EndTable() to add the view to the SQLITE_MASTER table */
sqlite3EndTable(pParse, 0, &sEnd, 0);
return;
}
#endif /* SQLITE_OMIT_VIEW */
#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE)
/*
** The Table structure pTable is really a VIEW. Fill in the names of
** the columns of the view in the pTable structure. Return the number
** of errors. If an error is seen leave an error message in pParse->zErrMsg.
*/
SQLITE_PRIVATE int sqlite3ViewGetColumnNames(Parse *pParse, Table *pTable){
Table *pSelTab; /* A fake table from which we get the result set */
Select *pSel; /* Copy of the SELECT that implements the view */
int nErr = 0; /* Number of errors encountered */
int n; /* Temporarily holds the number of cursors assigned */
sqlite3 *db = pParse->db; /* Database connection for malloc errors */
int (*xAuth)(void*,int,const char*,const char*,const char*,const char*);
assert( pTable );
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( sqlite3VtabCallConnect(pParse, pTable) ){
return SQLITE_ERROR;
}
if( IsVirtual(pTable) ) return 0;
#endif
#ifndef SQLITE_OMIT_VIEW
/* A positive nCol means the columns names for this view are
** already known.
*/
if( pTable->nCol>0 ) return 0;
/* A negative nCol is a special marker meaning that we are currently
** trying to compute the column names. If we enter this routine with
** a negative nCol, it means two or more views form a loop, like this:
**
** CREATE VIEW one AS SELECT * FROM two;
** CREATE VIEW two AS SELECT * FROM one;
**
** Actually, this error is caught previously and so the following test
** should always fail. But we will leave it in place just to be safe.
*/
if( pTable->nCol<0 ){
sqlite3ErrorMsg(pParse, "view %s is circularly defined", pTable->zName);
return 1;
}
assert( pTable->nCol>=0 );
/* If we get this far, it means we need to compute the table names.
** Note that the call to sqlite3ResultSetOfSelect() will expand any
** "*" elements in the results set of the view and will assign cursors
** to the elements of the FROM clause. But we do not want these changes
** to be permanent. So the computation is done on a copy of the SELECT
** statement that defines the view.
*/
assert( pTable->pSelect );
pSel = sqlite3SelectDup(db, pTable->pSelect);
if( pSel ){
n = pParse->nTab;
sqlite3SrcListAssignCursors(pParse, pSel->pSrc);
pTable->nCol = -1;
#ifndef SQLITE_OMIT_AUTHORIZATION
xAuth = db->xAuth;
db->xAuth = 0;
pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
db->xAuth = xAuth;
#else
pSelTab = sqlite3ResultSetOfSelect(pParse, 0, pSel);
#endif
pParse->nTab = n;
if( pSelTab ){
assert( pTable->aCol==0 );
pTable->nCol = pSelTab->nCol;
pTable->aCol = pSelTab->aCol;
pSelTab->nCol = 0;
pSelTab->aCol = 0;
sqlite3DeleteTable(pSelTab);
pTable->pSchema->flags |= DB_UnresetViews;
}else{
pTable->nCol = 0;
nErr++;
}
sqlite3SelectDelete(db, pSel);
} else {
nErr++;
}
#endif /* SQLITE_OMIT_VIEW */
return nErr;
}
#endif /* !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_VIRTUALTABLE) */
#ifndef SQLITE_OMIT_VIEW
/*
** Clear the column names from every VIEW in database idx.
*/
static void sqliteViewResetAll(sqlite3 *db, int idx){
HashElem *i;
if( !DbHasProperty(db, idx, DB_UnresetViews) ) return;
for(i=sqliteHashFirst(&db->aDb[idx].pSchema->tblHash); i;i=sqliteHashNext(i)){
Table *pTab = sqliteHashData(i);
if( pTab->pSelect ){
sqliteResetColumnNames(pTab);
}
}
DbClearProperty(db, idx, DB_UnresetViews);
}
#else
# define sqliteViewResetAll(A,B)
#endif /* SQLITE_OMIT_VIEW */
/*
sqlite-amalgamation.c view on Meta::CPAN
pFromCol->a[i].zName);
goto fk_end;
}
}
}
if( pToCol ){
for(i=0; i<nCol; i++){
int n = strlen(pToCol->a[i].zName);
pFKey->aCol[i].zCol = z;
memcpy(z, pToCol->a[i].zName, n);
z[n] = 0;
z += n+1;
}
}
pFKey->isDeferred = 0;
pFKey->deleteConf = flags & 0xff;
pFKey->updateConf = (flags >> 8 ) & 0xff;
pFKey->insertConf = (flags >> 16 ) & 0xff;
/* Link the foreign key to the table as the last step.
*/
p->pFKey = pFKey;
pFKey = 0;
fk_end:
sqlite3DbFree(db, pFKey);
#endif /* !defined(SQLITE_OMIT_FOREIGN_KEY) */
sqlite3ExprListDelete(db, pFromCol);
sqlite3ExprListDelete(db, pToCol);
}
/*
** This routine is called when an INITIALLY IMMEDIATE or INITIALLY DEFERRED
** clause is seen as part of a foreign key definition. The isDeferred
** parameter is 1 for INITIALLY DEFERRED and 0 for INITIALLY IMMEDIATE.
** The behavior of the most recently created foreign key is adjusted
** accordingly.
*/
SQLITE_PRIVATE void sqlite3DeferForeignKey(Parse *pParse, int isDeferred){
#ifndef SQLITE_OMIT_FOREIGN_KEY
Table *pTab;
FKey *pFKey;
if( (pTab = pParse->pNewTable)==0 || (pFKey = pTab->pFKey)==0 ) return;
pFKey->isDeferred = isDeferred;
#endif
}
/*
** Generate code that will erase and refill index *pIdx. This is
** used to initialize a newly created index or to recompute the
** content of an index in response to a REINDEX command.
**
** if memRootPage is not negative, it means that the index is newly
** created. The register specified by memRootPage contains the
** root page number of the index. If memRootPage is negative, then
** the index already exists and must be cleared before being refilled and
** the root page number of the index is taken from pIndex->tnum.
*/
static void sqlite3RefillIndex(Parse *pParse, Index *pIndex, int memRootPage){
Table *pTab = pIndex->pTable; /* The table that is indexed */
int iTab = pParse->nTab; /* Btree cursor used for pTab */
int iIdx = pParse->nTab+1; /* Btree cursor used for pIndex */
int addr1; /* Address of top of loop */
int tnum; /* Root page of index */
Vdbe *v; /* Generate code into this virtual machine */
KeyInfo *pKey; /* KeyInfo for index */
int regIdxKey; /* Registers containing the index key */
int regRecord; /* Register holding assemblied index record */
sqlite3 *db = pParse->db; /* The database connection */
int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse, SQLITE_REINDEX, pIndex->zName, 0,
db->aDb[iDb].zName ) ){
return;
}
#endif
/* Require a write-lock on the table to perform this operation */
sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
if( memRootPage>=0 ){
tnum = memRootPage;
}else{
tnum = pIndex->tnum;
sqlite3VdbeAddOp2(v, OP_Clear, tnum, iDb);
}
pKey = sqlite3IndexKeyinfo(pParse, pIndex);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iIdx, tnum, iDb,
(char *)pKey, P4_KEYINFO_HANDOFF);
if( memRootPage>=0 ){
sqlite3VdbeChangeP5(v, 1);
}
sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
regRecord = sqlite3GetTempReg(pParse);
regIdxKey = sqlite3GenerateIndexKey(pParse, pIndex, iTab, regRecord, 1);
if( pIndex->onError!=OE_None ){
int j1, j2;
int regRowid;
regRowid = regIdxKey + pIndex->nColumn;
j1 = sqlite3VdbeAddOp3(v, OP_IsNull, regIdxKey, 0, pIndex->nColumn);
j2 = sqlite3VdbeAddOp4(v, OP_IsUnique, iIdx,
0, regRowid, SQLITE_INT_TO_PTR(regRecord), P4_INT32);
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, OE_Abort, 0,
"indexed columns are not unique", P4_STATIC);
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeJumpHere(v, j2);
}
sqlite3VdbeAddOp2(v, OP_IdxInsert, iIdx, regRecord);
sqlite3ReleaseTempReg(pParse, regRecord);
sqlite3VdbeAddOp2(v, OP_Next, iTab, addr1+1);
sqlite3VdbeJumpHere(v, addr1);
sqlite3VdbeAddOp1(v, OP_Close, iTab);
sqlite3VdbeAddOp1(v, OP_Close, iIdx);
}
/*
** Create a new index for an SQL table. pName1.pName2 is the name of the index
sqlite-amalgamation.c view on Meta::CPAN
** database name prefix. Like this: "database.table". The pDatabase
** points to the table name and the pTable points to the database name.
** The SrcList.a[].zName field is filled with the table name which might
** come from pTable (if pDatabase is NULL) or from pDatabase.
** SrcList.a[].zDatabase is filled with the database name from pTable,
** or with NULL if no database is specified.
**
** In other words, if call like this:
**
** sqlite3SrcListAppend(D,A,B,0);
**
** Then B is a table name and the database name is unspecified. If called
** like this:
**
** sqlite3SrcListAppend(D,A,B,C);
**
** Then C is the table name and B is the database name.
*/
SQLITE_PRIVATE SrcList *sqlite3SrcListAppend(
sqlite3 *db, /* Connection to notify of malloc failures */
SrcList *pList, /* Append to this SrcList. NULL creates a new SrcList */
Token *pTable, /* Table to append */
Token *pDatabase /* Database of the table */
){
struct SrcList_item *pItem;
if( pList==0 ){
pList = sqlite3DbMallocZero(db, sizeof(SrcList) );
if( pList==0 ) return 0;
pList->nAlloc = 1;
}
if( pList->nSrc>=pList->nAlloc ){
SrcList *pNew;
pList->nAlloc *= 2;
pNew = sqlite3DbRealloc(db, pList,
sizeof(*pList) + (pList->nAlloc-1)*sizeof(pList->a[0]) );
if( pNew==0 ){
sqlite3SrcListDelete(db, pList);
return 0;
}
pList = pNew;
}
pItem = &pList->a[pList->nSrc];
memset(pItem, 0, sizeof(pList->a[0]));
if( pDatabase && pDatabase->z==0 ){
pDatabase = 0;
}
if( pDatabase && pTable ){
Token *pTemp = pDatabase;
pDatabase = pTable;
pTable = pTemp;
}
pItem->zName = sqlite3NameFromToken(db, pTable);
pItem->zDatabase = sqlite3NameFromToken(db, pDatabase);
pItem->iCursor = -1;
pItem->isPopulated = 0;
pList->nSrc++;
return pList;
}
/*
** Assign cursors to all tables in a SrcList
*/
SQLITE_PRIVATE void sqlite3SrcListAssignCursors(Parse *pParse, SrcList *pList){
int i;
struct SrcList_item *pItem;
assert(pList || pParse->db->mallocFailed );
if( pList ){
for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){
if( pItem->iCursor>=0 ) break;
pItem->iCursor = pParse->nTab++;
if( pItem->pSelect ){
sqlite3SrcListAssignCursors(pParse, pItem->pSelect->pSrc);
}
}
}
}
/*
** Delete an entire SrcList including all its substructure.
*/
SQLITE_PRIVATE void sqlite3SrcListDelete(sqlite3 *db, SrcList *pList){
int i;
struct SrcList_item *pItem;
if( pList==0 ) return;
for(pItem=pList->a, i=0; i<pList->nSrc; i++, pItem++){
sqlite3DbFree(db, pItem->zDatabase);
sqlite3DbFree(db, pItem->zName);
sqlite3DbFree(db, pItem->zAlias);
sqlite3DeleteTable(pItem->pTab);
sqlite3SelectDelete(db, pItem->pSelect);
sqlite3ExprDelete(db, pItem->pOn);
sqlite3IdListDelete(db, pItem->pUsing);
}
sqlite3DbFree(db, pList);
}
/*
** This routine is called by the parser to add a new term to the
** end of a growing FROM clause. The "p" parameter is the part of
** the FROM clause that has already been constructed. "p" is NULL
** if this is the first term of the FROM clause. pTable and pDatabase
** are the name of the table and database named in the FROM clause term.
** pDatabase is NULL if the database name qualifier is missing - the
** usual case. If the term has a alias, then pAlias points to the
** alias token. If the term is a subquery, then pSubquery is the
** SELECT statement that the subquery encodes. The pTable and
** pDatabase parameters are NULL for subqueries. The pOn and pUsing
** parameters are the content of the ON and USING clauses.
**
** Return a new SrcList which encodes is the FROM with the new
** term added.
*/
SQLITE_PRIVATE SrcList *sqlite3SrcListAppendFromTerm(
Parse *pParse, /* Parsing context */
SrcList *p, /* The left part of the FROM clause already seen */
Token *pTable, /* Name of the table to add to the FROM clause */
Token *pDatabase, /* Name of the database containing pTable */
Token *pAlias, /* The right-hand side of the AS subexpression */
Select *pSubquery, /* A subquery used in place of a table name */
Expr *pOn, /* The ON clause of a join */
IdList *pUsing /* The USING clause of a join */
sqlite-amalgamation.c view on Meta::CPAN
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains C code routines that are called by the parser
** in order to generate code for DELETE FROM statements.
**
** $Id: delete.c,v 1.171 2008/07/28 19:34:53 drh Exp $
*/
/*
** Look up every table that is named in pSrc. If any table is not found,
** add an error message to pParse->zErrMsg and return NULL. If all tables
** are found, return a pointer to the last table.
*/
SQLITE_PRIVATE Table *sqlite3SrcListLookup(Parse *pParse, SrcList *pSrc){
Table *pTab = 0;
int i;
struct SrcList_item *pItem;
for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){
pTab = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase);
sqlite3DeleteTable(pItem->pTab);
pItem->pTab = pTab;
if( pTab ){
pTab->nRef++;
}
}
return pTab;
}
/*
** Check to make sure the given table is writable. If it is not
** writable, generate an error message and return 1. If it is
** writable return 0;
*/
SQLITE_PRIVATE int sqlite3IsReadOnly(Parse *pParse, Table *pTab, int viewOk){
if( (pTab->readOnly && (pParse->db->flags & SQLITE_WriteSchema)==0
&& pParse->nested==0)
#ifndef SQLITE_OMIT_VIRTUALTABLE
|| (pTab->pMod && pTab->pMod->pModule->xUpdate==0)
#endif
){
sqlite3ErrorMsg(pParse, "table %s may not be modified", pTab->zName);
return 1;
}
#ifndef SQLITE_OMIT_VIEW
if( !viewOk && pTab->pSelect ){
sqlite3ErrorMsg(pParse,"cannot modify %s because it is a view",pTab->zName);
return 1;
}
#endif
return 0;
}
/*
** Generate code that will open a table for reading.
*/
SQLITE_PRIVATE void sqlite3OpenTable(
Parse *p, /* Generate code into this VDBE */
int iCur, /* The cursor number of the table */
int iDb, /* The database index in sqlite3.aDb[] */
Table *pTab, /* The table to be opened */
int opcode /* OP_OpenRead or OP_OpenWrite */
){
Vdbe *v;
if( IsVirtual(pTab) ) return;
v = sqlite3GetVdbe(p);
assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite), pTab->zName);
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
VdbeComment((v, "%s", pTab->zName));
}
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
/*
** Evaluate a view and store its result in an ephemeral table. The
** pWhere argument is an optional WHERE clause that restricts the
** set of rows in the view that are to be added to the ephemeral table.
*/
SQLITE_PRIVATE void sqlite3MaterializeView(
Parse *pParse, /* Parsing context */
Select *pView, /* View definition */
Expr *pWhere, /* Optional WHERE clause to be added */
int iCur /* Cursor number for ephemerial table */
){
SelectDest dest;
Select *pDup;
sqlite3 *db = pParse->db;
pDup = sqlite3SelectDup(db, pView);
if( pWhere ){
SrcList *pFrom;
pWhere = sqlite3ExprDup(db, pWhere);
pFrom = sqlite3SrcListAppendFromTerm(pParse, 0, 0, 0, 0, pDup, 0, 0);
pDup = sqlite3SelectNew(pParse, 0, pFrom, pWhere, 0, 0, 0, 0, 0, 0);
}
sqlite3SelectDestInit(&dest, SRT_EphemTab, iCur);
sqlite3Select(pParse, pDup, &dest, 0, 0, 0);
sqlite3SelectDelete(db, pDup);
}
#endif /* !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER) */
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
SQLITE_PRIVATE void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
sqlite-amalgamation.c view on Meta::CPAN
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = 0; /* Memory cell used for change counting */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
int triggers_exist = 0; /* True if any triggers exist */
#endif
int iBeginAfterTrigger; /* Address of after trigger program */
int iEndAfterTrigger; /* Exit of after trigger program */
int iBeginBeforeTrigger; /* Address of before trigger program */
int iEndBeforeTrigger; /* Exit of before trigger program */
u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
if( sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb) ){
goto delete_from_cleanup;
}
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
/* Allocate a cursor used to store the old.* data for a trigger.
*/
if( triggers_exist ){
oldIdx = pParse->nTab++;
}
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);
if( triggers_exist ){
int orconf = ((pParse->trigStack)?pParse->trigStack->orconf:OE_Default);
int iGoto = sqlite3VdbeAddOp0(v, OP_Goto);
addr = sqlite3VdbeMakeLabel(v);
iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
-1, oldIdx, orconf, addr, &old_col_mask, 0);
iEndBeforeTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
oldIdx, orconf, addr, &old_col_mask, 0);
iEndAfterTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, iGoto);
}
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
if( isView ){
sqlite3MaterializeView(pParse, pTab->pSelect, pWhere, iCur);
}
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ExprResolveNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
sqlite-amalgamation.c view on Meta::CPAN
if( db->flags & SQLITE_CountRows ){
/* If counting rows deleted, just count the total number of
** entries in the table. */
int addr2;
if( !isView ){
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
}
sqlite3VdbeAddOp2(v, OP_Rewind, iCur, sqlite3VdbeCurrentAddr(v)+2);
addr2 = sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
sqlite3VdbeAddOp2(v, OP_Next, iCur, addr2);
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
if( !isView ){
sqlite3VdbeAddOp2(v, OP_Clear, pTab->tnum, iDb);
if( !pParse->nested ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
}
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}
}
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
else{
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
/* Begin the database scan
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
if( pWInfo==0 ) goto delete_from_cleanup;
/* Remember the rowid of every item to be deleted.
*/
sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, iRowid);
sqlite3VdbeAddOp1(v, OP_FifoWrite, iRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Open the pseudo-table used to store OLD if there are triggers.
*/
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
}
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order.
*/
end = sqlite3VdbeMakeLabel(v);
if( !isView ){
/* Open cursors for the table we are deleting from and
** all its indices.
*/
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
/* This is the beginning of the delete loop. If a trigger encounters
** an IGNORE constraint, it jumps back to here.
*/
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
addr = sqlite3VdbeAddOp2(v, OP_FifoRead, iRowid, end);
if( triggers_exist ){
int iData = ++pParse->nMem; /* For storing row data of OLD table */
/* If the record is no longer present in the table, jump to the
** next iteration of the loop through the contents of the fifo.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
/* Populate the OLD.* pseudo-table */
if( old_col_mask ){
sqlite3VdbeAddOp2(v, OP_RowData, iCur, iData);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, iData);
}
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);
/* Jump back and run the BEFORE triggers */
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
}
if( !isView ){
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVtab = (const char *)pTab->pVtab;
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
}else
#endif
{
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, pParse->nested==0);
}
}
/* If there are row triggers, close all cursors then invoke
** the AFTER triggers
*/
if( triggers_exist ){
/* Jump back and run the AFTER triggers */
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors after the loop if there are no row triggers */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/*
** Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", P4_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** This routine generates VDBE code that causes a single row of a
** single table to be deleted.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number "base".
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number base+i for the i-th index.
**
** 3. The record number of the row to be deleted must be stored in
** memory cell iRowid.
**
** This routine pops the top of the stack to remove the record number
** and then generates code to remove both the table record and all index
** entries that point to that record.
*/
SQLITE_PRIVATE void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int iRowid, /* Memory cell that contains the rowid to delete */
int count /* Increment the row change counter */
){
int addr;
Vdbe *v;
v = pParse->pVdbe;
addr = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
if( count ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
}
sqlite3VdbeJumpHere(v, addr);
}
/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number "iCur".
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number iCur+i for the i-th index.
**
** 3. The "iCur" cursor must be pointing to the row that is to be
** deleted.
*/
SQLITE_PRIVATE void sqlite3GenerateRowIndexDelete(
Parse *pParse, /* Parsing and code generating context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int *aRegIdx /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
){
int i;
Index *pIdx;
int r1;
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
}
}
/*
** Generate code that will assemble an index key and put it in register
** regOut. The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key. The
** block of registers has already been deallocated by the time
** this routine returns.
*/
SQLITE_PRIVATE int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iCur, /* Cursor number for the pIdx->pTable table */
int regOut, /* Write the new index key to this register */
int doMakeRec /* Run the OP_MakeRecord instruction if true */
){
Vdbe *v = pParse->pVdbe;
int j;
Table *pTab = pIdx->pTable;
int regBase;
int nCol;
nCol = pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol+1);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
for(j=0; j<nCol; j++){
int idx = pIdx->aiColumn[j];
if( idx==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
}else{
sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
sqlite3ColumnDefault(v, pTab, idx);
}
}
if( doMakeRec ){
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
sqlite3IndexAffinityStr(v, pIdx);
sqlite3ExprCacheAffinityChange(pParse, regBase, nCol+1);
}
sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
return regBase;
}
/* Make sure "isView" gets undefined in case this file becomes part of
** the amalgamation - so that subsequent files do not see isView as a
** macro. */
#undef isView
/************** End of delete.c **********************************************/
/************** Begin file func.c ********************************************/
/*
** 2002 February 23
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This file contains the C functions that implement various SQL
sqlite-amalgamation.c view on Meta::CPAN
int memId /* Memory cell holding the maximum rowid */
){
if( pTab->autoInc ){
int iCur = pParse->nTab;
Vdbe *v = pParse->pVdbe;
Db *pDb = &pParse->db->aDb[iDb];
int j1;
int iRec = ++pParse->nMem; /* Memory cell used for record */
assert( v );
sqlite3OpenTable(pParse, iCur, iDb, pDb->pSchema->pSeqTab, OP_OpenWrite);
j1 = sqlite3VdbeAddOp1(v, OP_NotNull, memId+1);
sqlite3VdbeAddOp2(v, OP_NewRowid, iCur, memId+1);
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeAddOp3(v, OP_MakeRecord, memId-1, 2, iRec);
sqlite3VdbeAddOp3(v, OP_Insert, iCur, iRec, memId+1);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
#else
/*
** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines
** above are all no-ops
*/
# define autoIncBegin(A,B,C) (0)
# define autoIncStep(A,B,C)
# define autoIncEnd(A,B,C,D)
#endif /* SQLITE_OMIT_AUTOINCREMENT */
/* Forward declaration */
static int xferOptimization(
Parse *pParse, /* Parser context */
Table *pDest, /* The table we are inserting into */
Select *pSelect, /* A SELECT statement to use as the data source */
int onError, /* How to handle constraint errors */
int iDbDest /* The database of pDest */
);
/*
** This routine is call to handle SQL of the following forms:
**
** insert into TABLE (IDLIST) values(EXPRLIST)
** insert into TABLE (IDLIST) select
**
** The IDLIST following the table name is always optional. If omitted,
** then a list of all columns for the table is substituted. The IDLIST
** appears in the pColumn parameter. pColumn is NULL if IDLIST is omitted.
**
** The pList parameter holds EXPRLIST in the first form of the INSERT
** statement above, and pSelect is NULL. For the second form, pList is
** NULL and pSelect is a pointer to the select statement used to generate
** data for the insert.
**
** The code generated follows one of four templates. For a simple
** select with data coming from a VALUES clause, the code executes
** once straight down through. Pseudo-code follows (we call this
** the "1st template"):
**
** open write cursor to <table> and its indices
** puts VALUES clause expressions onto the stack
** write the resulting record into <table>
** cleanup
**
** The three remaining templates assume the statement is of the form
**
** INSERT INTO <table> SELECT ...
**
** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" -
** in other words if the SELECT pulls all columns from a single table
** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and
** if <table2> and <table1> are distinct tables but have identical
** schemas, including all the same indices, then a special optimization
** is invoked that copies raw records from <table2> over to <table1>.
** See the xferOptimization() function for the implementation of this
** template. This is the 2nd template.
**
** open a write cursor to <table>
** open read cursor on <table2>
** transfer all records in <table2> over to <table>
** close cursors
** foreach index on <table>
** open a write cursor on the <table> index
** open a read cursor on the corresponding <table2> index
** transfer all records from the read to the write cursors
** close cursors
** end foreach
**
** The 3rd template is for when the second template does not apply
** and the SELECT clause does not read from <table> at any time.
** The generated code follows this template:
**
** EOF <- 0
** X <- A
** goto B
** A: setup for the SELECT
** loop over the rows in the SELECT
** load values into registers R..R+n
** yield X
** end loop
** cleanup after the SELECT
** EOF <- 1
** yield X
** goto A
** B: open write cursor to <table> and its indices
** C: yield X
** if EOF goto D
** insert the select result into <table> from R..R+n
** goto C
** D: cleanup
**
** The 4th template is used if the insert statement takes its
** values from a SELECT but the data is being inserted into a table
** that is also read as part of the SELECT. In the third form,
** we have to use a intermediate table to store the results of
** the select. The template is like this:
**
** EOF <- 0
** X <- A
** goto B
** A: setup for the SELECT
** loop over the tables in the SELECT
** load value into register R..R+n
** yield X
** end loop
** cleanup after the SELECT
** EOF <- 1
** yield X
** halt-error
** B: open temp table
** L: yield X
** if EOF goto M
** insert row from R..R+n into temp table
** goto L
** M: open write cursor to <table> and its indices
** rewind temp table
** C: loop over rows of intermediate table
** transfer values form intermediate table into <table>
** end loop
** D: cleanup
*/
SQLITE_PRIVATE void sqlite3Insert(
Parse *pParse, /* Parser context */
SrcList *pTabList, /* Name of table into which we are inserting */
ExprList *pList, /* List of values to be inserted */
Select *pSelect, /* A SELECT statement to use as the data source */
IdList *pColumn, /* Column names corresponding to IDLIST. */
int onError /* How to handle constraint errors */
){
sqlite3 *db; /* The main database structure */
Table *pTab; /* The table to insert into. aka TABLE */
char *zTab; /* Name of the table into which we are inserting */
const char *zDb; /* Name of the database holding this table */
int i, j, idx; /* Loop counters */
Vdbe *v; /* Generate code into this virtual machine */
Index *pIdx; /* For looping over indices of the table */
int nColumn; /* Number of columns in the data */
int nHidden = 0; /* Number of hidden columns if TABLE is virtual */
int baseCur = 0; /* VDBE Cursor number for pTab */
int keyColumn = -1; /* Column that is the INTEGER PRIMARY KEY */
int endOfLoop; /* Label for the end of the insertion loop */
int useTempTable = 0; /* Store SELECT results in intermediate table */
int srcTab = 0; /* Data comes from this temporary cursor if >=0 */
int addrInsTop = 0; /* Jump to label "D" */
int addrCont = 0; /* Top of insert loop. Label "C" in templates 3 and 4 */
int addrSelect = 0; /* Address of coroutine that implements the SELECT */
SelectDest dest; /* Destination for SELECT on rhs of INSERT */
int newIdx = -1; /* Cursor for the NEW pseudo-table */
int iDb; /* Index of database holding TABLE */
Db *pDb; /* The database containing table being inserted into */
int appendFlag = 0; /* True if the insert is likely to be an append */
/* Register allocations */
int regFromSelect; /* Base register for data coming from SELECT */
int regAutoinc = 0; /* Register holding the AUTOINCREMENT counter */
int regRowCount = 0; /* Memory cell used for the row counter */
int regIns; /* Block of regs holding rowid+data being inserted */
int regRowid; /* registers holding insert rowid */
int regData; /* register holding first column to insert */
int regRecord; /* Holds the assemblied row record */
int regEof; /* Register recording end of SELECT data */
int *aRegIdx = 0; /* One register allocated to each index */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to insert into a view */
int triggers_exist = 0; /* True if there are FOR EACH ROW triggers */
#endif
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto insert_cleanup;
}
/* Locate the table into which we will be inserting new information.
*/
assert( pTabList->nSrc==1 );
zTab = pTabList->a[0].zName;
if( zTab==0 ) goto insert_cleanup;
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ){
goto insert_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
pDb = &db->aDb[iDb];
zDb = pDb->zName;
if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){
goto insert_cleanup;
}
/* Figure out if we have any triggers and if the table being
** inserted into is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
sqlite-amalgamation.c view on Meta::CPAN
** 3. The data in the first column of the entry after the update.
**
** i. Data from middle columns...
**
** N. The data in the last column of the entry after the update.
**
** The regRowid parameter is the index of the register containing (2).
**
** The old rowid shown as entry (1) above is omitted unless both isUpdate
** and rowidChng are 1. isUpdate is true for UPDATEs and false for
** INSERTs. RowidChng means that the new rowid is explicitly specified by
** the update or insert statement. If rowidChng is false, it means that
** the rowid is computed automatically in an insert or that the rowid value
** is not modified by the update.
**
** The code generated by this routine store new index entries into
** registers identified by aRegIdx[]. No index entry is created for
** indices where aRegIdx[i]==0. The order of indices in aRegIdx[] is
** the same as the order of indices on the linked list of indices
** attached to the table.
**
** This routine also generates code to check constraints. NOT NULL,
** CHECK, and UNIQUE constraints are all checked. If a constraint fails,
** then the appropriate action is performed. There are five possible
** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE.
**
** Constraint type Action What Happens
** --------------- ---------- ----------------------------------------
** any ROLLBACK The current transaction is rolled back and
** sqlite3_exec() returns immediately with a
** return code of SQLITE_CONSTRAINT.
**
** any ABORT Back out changes from the current command
** only (do not do a complete rollback) then
** cause sqlite3_exec() to return immediately
** with SQLITE_CONSTRAINT.
**
** any FAIL Sqlite_exec() returns immediately with a
** return code of SQLITE_CONSTRAINT. The
** transaction is not rolled back and any
** prior changes are retained.
**
** any IGNORE The record number and data is popped from
** the stack and there is an immediate jump
** to label ignoreDest.
**
** NOT NULL REPLACE The NULL value is replace by the default
** value for that column. If the default value
** is NULL, the action is the same as ABORT.
**
** UNIQUE REPLACE The other row that conflicts with the row
** being inserted is removed.
**
** CHECK REPLACE Illegal. The results in an exception.
**
** Which action to take is determined by the overrideError parameter.
** Or if overrideError==OE_Default, then the pParse->onError parameter
** is used. Or if pParse->onError==OE_Default then the onError value
** for the constraint is used.
**
** The calling routine must open a read/write cursor for pTab with
** cursor number "baseCur". All indices of pTab must also have open
** read/write cursors with cursor number baseCur+i for the i-th cursor.
** Except, if there is no possibility of a REPLACE action then
** cursors do not need to be open for indices where aRegIdx[i]==0.
*/
SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int baseCur, /* Index of a read/write cursor pointing at pTab */
int regRowid, /* Index of the range of input registers */
int *aRegIdx, /* Register used by each index. 0 for unused indices */
int rowidChng, /* True if the rowid might collide with existing entry */
int isUpdate, /* True for UPDATE, False for INSERT */
int overrideError, /* Override onError to this if not OE_Default */
int ignoreDest /* Jump to this label on an OE_Ignore resolution */
){
int i;
Vdbe *v;
int nCol;
int onError;
int j1, j2, j3; /* Addresses of jump instructions */
int regData; /* Register containing first data column */
int iCur;
Index *pIdx;
int seenReplace = 0;
int hasTwoRowids = (isUpdate && rowidChng);
v = sqlite3GetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
nCol = pTab->nCol;
regData = regRowid + 1;
/* Test all NOT NULL constraints.
*/
for(i=0; i<nCol; i++){
if( i==pTab->iPKey ){
continue;
}
onError = pTab->aCol[i].notNull;
if( onError==OE_None ) continue;
if( overrideError!=OE_Default ){
onError = overrideError;
}else if( onError==OE_Default ){
onError = OE_Abort;
}
if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){
onError = OE_Abort;
}
j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regData+i);
assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail
|| onError==OE_Ignore || onError==OE_Replace );
switch( onError ){
case OE_Rollback:
case OE_Abort:
case OE_Fail: {
char *zMsg;
sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_CONSTRAINT, onError);
zMsg = sqlite3MPrintf(pParse->db, "%s.%s may not be NULL",
pTab->zName, pTab->aCol[i].zName);
sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC);
break;
}
case OE_Ignore: {
sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
break;
}
case OE_Replace: {
sqlite-amalgamation.c view on Meta::CPAN
|| onError==OE_Ignore || onError==OE_Replace );
switch( onError ){
case OE_Rollback:
case OE_Abort:
case OE_Fail: {
int j, n1, n2;
char zErrMsg[200];
sqlite3_snprintf(sizeof(zErrMsg), zErrMsg,
pIdx->nColumn>1 ? "columns " : "column ");
n1 = strlen(zErrMsg);
for(j=0; j<pIdx->nColumn && n1<sizeof(zErrMsg)-30; j++){
char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName;
n2 = strlen(zCol);
if( j>0 ){
sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], ", ");
n1 += 2;
}
if( n1+n2>sizeof(zErrMsg)-30 ){
sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "...");
n1 += 3;
break;
}else{
sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1], "%s", zCol);
n1 += n2;
}
}
sqlite3_snprintf(sizeof(zErrMsg)-n1, &zErrMsg[n1],
pIdx->nColumn>1 ? " are not unique" : " is not unique");
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CONSTRAINT, onError, 0, zErrMsg,0);
break;
}
case OE_Ignore: {
assert( seenReplace==0 );
sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest);
break;
}
case OE_Replace: {
sqlite3GenerateRowDelete(pParse, pTab, baseCur, regR, 0);
seenReplace = 1;
break;
}
}
sqlite3VdbeJumpHere(v, j2);
sqlite3VdbeJumpHere(v, j3);
sqlite3ReleaseTempReg(pParse, regR);
}
}
/*
** This routine generates code to finish the INSERT or UPDATE operation
** that was started by a prior call to sqlite3GenerateConstraintChecks.
** A consecutive range of registers starting at regRowid contains the
** rowid and the content to be inserted.
**
** The arguments to this routine should be the same as the first six
** arguments to sqlite3GenerateConstraintChecks.
*/
SQLITE_PRIVATE void sqlite3CompleteInsertion(
Parse *pParse, /* The parser context */
Table *pTab, /* the table into which we are inserting */
int baseCur, /* Index of a read/write cursor pointing at pTab */
int regRowid, /* Range of content */
int *aRegIdx, /* Register used by each index. 0 for unused indices */
int rowidChng, /* True if the record number will change */
int isUpdate, /* True for UPDATE, False for INSERT */
int newIdx, /* Index of NEW table for triggers. -1 if none */
int appendBias /* True if this is likely to be an append */
){
int i;
Vdbe *v;
int nIdx;
Index *pIdx;
int pik_flags;
int regData;
int regRec;
v = sqlite3GetVdbe(pParse);
assert( v!=0 );
assert( pTab->pSelect==0 ); /* This table is not a VIEW */
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
for(i=nIdx-1; i>=0; i--){
if( aRegIdx[i]==0 ) continue;
sqlite3VdbeAddOp2(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i]);
}
regData = regRowid + 1;
regRec = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec);
sqlite3TableAffinityStr(v, pTab);
sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol);
#ifndef SQLITE_OMIT_TRIGGER
if( newIdx>=0 ){
sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRec, regRowid);
}
#endif
if( pParse->nested ){
pik_flags = 0;
}else{
pik_flags = OPFLAG_NCHANGE;
pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID);
}
if( appendBias ){
pik_flags |= OPFLAG_APPEND;
}
sqlite3VdbeAddOp3(v, OP_Insert, baseCur, regRec, regRowid);
if( !pParse->nested ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
}
sqlite3VdbeChangeP5(v, pik_flags);
}
/*
** Generate code that will open cursors for a table and for all
** indices of that table. The "baseCur" parameter is the cursor number used
** for the table. Indices are opened on subsequent cursors.
**
** Return the number of indices on the table.
*/
SQLITE_PRIVATE int sqlite3OpenTableAndIndices(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table to be opened */
int baseCur, /* Cursor number assigned to the table */
int op /* OP_OpenRead or OP_OpenWrite */
){
int i;
int iDb;
Index *pIdx;
Vdbe *v;
if( IsVirtual(pTab) ) return 0;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
v = sqlite3GetVdbe(pParse);
assert( v!=0 );
sqlite3OpenTable(pParse, baseCur, iDb, pTab, op);
for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp4(v, op, i+baseCur, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
}
if( pParse->nTab<=baseCur+i ){
pParse->nTab = baseCur+i;
}
return i-1;
}
#ifdef SQLITE_TEST
/*
** The following global variable is incremented whenever the
** transfer optimization is used. This is used for testing
** purposes only - to make sure the transfer optimization really
** is happening when it is suppose to.
*/
SQLITE_API int sqlite3_xferopt_count;
#endif /* SQLITE_TEST */
#ifndef SQLITE_OMIT_XFER_OPT
/*
** Check to collation names to see if they are compatible.
*/
static int xferCompatibleCollation(const char *z1, const char *z2){
if( z1==0 ){
return z2==0;
}
if( z2==0 ){
return 0;
}
return sqlite3StrICmp(z1, z2)==0;
}
/*
sqlite-amalgamation.c view on Meta::CPAN
*/
static const char master_schema[] =
"CREATE TABLE sqlite_master(\n"
" type text,\n"
" name text,\n"
" tbl_name text,\n"
" rootpage integer,\n"
" sql text\n"
")"
;
#ifndef SQLITE_OMIT_TEMPDB
static const char temp_master_schema[] =
"CREATE TEMP TABLE sqlite_temp_master(\n"
" type text,\n"
" name text,\n"
" tbl_name text,\n"
" rootpage integer,\n"
" sql text\n"
")"
;
#else
#define temp_master_schema 0
#endif
assert( iDb>=0 && iDb<db->nDb );
assert( db->aDb[iDb].pSchema );
assert( sqlite3_mutex_held(db->mutex) );
assert( iDb==1 || sqlite3BtreeHoldsMutex(db->aDb[iDb].pBt) );
/* zMasterSchema and zInitScript are set to point at the master schema
** and initialisation script appropriate for the database being
** initialised. zMasterName is the name of the master table.
*/
if( !OMIT_TEMPDB && iDb==1 ){
zMasterSchema = temp_master_schema;
}else{
zMasterSchema = master_schema;
}
zMasterName = SCHEMA_TABLE(iDb);
/* Construct the schema tables. */
azArg[0] = zMasterName;
azArg[1] = "1";
azArg[2] = zMasterSchema;
azArg[3] = 0;
initData.db = db;
initData.iDb = iDb;
initData.pzErrMsg = pzErrMsg;
(void)sqlite3SafetyOff(db);
rc = sqlite3InitCallback(&initData, 3, (char **)azArg, 0);
(void)sqlite3SafetyOn(db);
if( rc ){
rc = initData.rc;
goto error_out;
}
pTab = sqlite3FindTable(db, zMasterName, db->aDb[iDb].zName);
if( pTab ){
pTab->readOnly = 1;
}
/* Create a cursor to hold the database open
*/
pDb = &db->aDb[iDb];
if( pDb->pBt==0 ){
if( !OMIT_TEMPDB && iDb==1 ){
DbSetProperty(db, 1, DB_SchemaLoaded);
}
return SQLITE_OK;
}
curMain = sqlite3MallocZero(sqlite3BtreeCursorSize());
if( !curMain ){
rc = SQLITE_NOMEM;
goto error_out;
}
sqlite3BtreeEnter(pDb->pBt);
rc = sqlite3BtreeCursor(pDb->pBt, MASTER_ROOT, 0, 0, curMain);
if( rc!=SQLITE_OK && rc!=SQLITE_EMPTY ){
sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
goto initone_error_out;
}
/* Get the database meta information.
**
** Meta values are as follows:
** meta[0] Schema cookie. Changes with each schema change.
** meta[1] File format of schema layer.
** meta[2] Size of the page cache.
** meta[3] Use freelist if 0. Autovacuum if greater than zero.
** meta[4] Db text encoding. 1:UTF-8 2:UTF-16LE 3:UTF-16BE
** meta[5] The user cookie. Used by the application.
** meta[6] Incremental-vacuum flag.
** meta[7]
** meta[8]
** meta[9]
**
** Note: The #defined SQLITE_UTF* symbols in sqliteInt.h correspond to
** the possible values of meta[4].
*/
if( rc==SQLITE_OK ){
int i;
for(i=0; i<sizeof(meta)/sizeof(meta[0]); i++){
rc = sqlite3BtreeGetMeta(pDb->pBt, i+1, (u32 *)&meta[i]);
if( rc ){
sqlite3SetString(pzErrMsg, db, "%s", sqlite3ErrStr(rc));
goto initone_error_out;
}
}
}else{
memset(meta, 0, sizeof(meta));
}
pDb->pSchema->schema_cookie = meta[0];
/* If opening a non-empty database, check the text encoding. For the
** main database, set sqlite3.enc to the encoding of the main database.
** For an attached db, it is an error if the encoding is not the same
** as sqlite3.enc.
*/
if( meta[4] ){ /* text encoding */
if( iDb==0 ){
/* If opening the main database, set ENC(db). */
ENC(db) = (u8)meta[4];
sqlite-amalgamation.c view on Meta::CPAN
static void setToken(Token *p, const char *z){
p->z = (u8*)z;
p->n = z ? strlen(z) : 0;
p->dyn = 0;
}
/*
** Set the token to the double-quoted and escaped version of the string pointed
** to by z. For example;
**
** {a"bc} -> {"a""bc"}
*/
static void setQuotedToken(Parse *pParse, Token *p, const char *z){
/* Check if the string contains any " characters. If it does, then
** this function will malloc space to create a quoted version of
** the string in. Otherwise, save a call to sqlite3MPrintf() by
** just copying the pointer to the string.
*/
const char *z2 = z;
while( *z2 ){
if( *z2=='"' ) break;
z2++;
}
if( *z2 ){
/* String contains " characters - copy and quote the string. */
p->z = (u8 *)sqlite3MPrintf(pParse->db, "\"%w\"", z);
if( p->z ){
p->n = strlen((char *)p->z);
p->dyn = 1;
}
}else{
/* String contains no " characters - copy the pointer. */
p->z = (u8*)z;
p->n = (z2 - z);
p->dyn = 0;
}
}
/*
** Create an expression node for an identifier with the name of zName
*/
SQLITE_PRIVATE Expr *sqlite3CreateIdExpr(Parse *pParse, const char *zName){
Token dummy;
setToken(&dummy, zName);
return sqlite3PExpr(pParse, TK_ID, 0, 0, &dummy);
}
/*
** Add a term to the WHERE expression in *ppExpr that requires the
** zCol column to be equal in the two tables pTab1 and pTab2.
*/
static void addWhereTerm(
Parse *pParse, /* Parsing context */
const char *zCol, /* Name of the column */
const Table *pTab1, /* First table */
const char *zAlias1, /* Alias for first table. May be NULL */
const Table *pTab2, /* Second table */
const char *zAlias2, /* Alias for second table. May be NULL */
int iRightJoinTable, /* VDBE cursor for the right table */
Expr **ppExpr, /* Add the equality term to this expression */
int isOuterJoin /* True if dealing with an OUTER join */
){
Expr *pE1a, *pE1b, *pE1c;
Expr *pE2a, *pE2b, *pE2c;
Expr *pE;
pE1a = sqlite3CreateIdExpr(pParse, zCol);
pE2a = sqlite3CreateIdExpr(pParse, zCol);
if( zAlias1==0 ){
zAlias1 = pTab1->zName;
}
pE1b = sqlite3CreateIdExpr(pParse, zAlias1);
if( zAlias2==0 ){
zAlias2 = pTab2->zName;
}
pE2b = sqlite3CreateIdExpr(pParse, zAlias2);
pE1c = sqlite3PExpr(pParse, TK_DOT, pE1b, pE1a, 0);
pE2c = sqlite3PExpr(pParse, TK_DOT, pE2b, pE2a, 0);
pE = sqlite3PExpr(pParse, TK_EQ, pE1c, pE2c, 0);
if( pE && isOuterJoin ){
ExprSetProperty(pE, EP_FromJoin);
pE->iRightJoinTable = iRightJoinTable;
}
*ppExpr = sqlite3ExprAnd(pParse->db,*ppExpr, pE);
}
/*
** Set the EP_FromJoin property on all terms of the given expression.
** And set the Expr.iRightJoinTable to iTable for every term in the
** expression.
**
** The EP_FromJoin property is used on terms of an expression to tell
** the LEFT OUTER JOIN processing logic that this term is part of the
** join restriction specified in the ON or USING clause and not a part
** of the more general WHERE clause. These terms are moved over to the
** WHERE clause during join processing but we need to remember that they
** originated in the ON or USING clause.
**
** The Expr.iRightJoinTable tells the WHERE clause processing that the
** expression depends on table iRightJoinTable even if that table is not
** explicitly mentioned in the expression. That information is needed
** for cases like this:
**
** SELECT * FROM t1 LEFT JOIN t2 ON t1.a=t2.b AND t1.x=5
**
** The where clause needs to defer the handling of the t1.x=5
** term until after the t2 loop of the join. In that way, a
** NULL t2 row will be inserted whenever t1.x!=5. If we do not
** defer the handling of t1.x=5, it will be processed immediately
** after the t1 loop and rows with t1.x!=5 will never appear in
** the output, which is incorrect.
*/
static void setJoinExpr(Expr *p, int iTable){
while( p ){
ExprSetProperty(p, EP_FromJoin);
p->iRightJoinTable = iTable;
setJoinExpr(p->pLeft, iTable);
p = p->pRight;
}
sqlite-amalgamation.c view on Meta::CPAN
if( (zName = pEList->a[i].zName)!=0 ){
/* If the column contains an "AS <name>" phrase, use <name> as the name */
zName = sqlite3DbStrDup(db, zName);
}else if( p->op==TK_COLUMN && p->pTab ){
/* For columns use the column name name */
int iCol = p->iColumn;
if( iCol<0 ) iCol = p->pTab->iPKey;
zName = sqlite3MPrintf(db, "%s", p->pTab->aCol[iCol].zName);
}else{
/* Use the original text of the column expression as its name */
zName = sqlite3MPrintf(db, "%T", &p->span);
}
if( db->mallocFailed ){
sqlite3DbFree(db, zName);
break;
}
sqlite3Dequote(zName);
/* Make sure the column name is unique. If the name is not unique,
** append a integer to the name so that it becomes unique.
*/
nName = strlen(zName);
for(j=cnt=0; j<i; j++){
if( sqlite3StrICmp(aCol[j].zName, zName)==0 ){
char *zNewName;
zName[nName] = 0;
zNewName = sqlite3MPrintf(db, "%s:%d", zName, ++cnt);
sqlite3DbFree(db, zName);
zName = zNewName;
j = -1;
if( zName==0 ) break;
}
}
pCol->zName = zName;
/* Get the typename, type affinity, and collating sequence for the
** column.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pSrcList = pSelect->pSrc;
zType = sqlite3DbStrDup(db, columnType(&sNC, p, 0, 0, 0));
pCol->zType = zType;
pCol->affinity = sqlite3ExprAffinity(p);
pColl = sqlite3ExprCollSeq(pParse, p);
if( pColl ){
pCol->zColl = sqlite3DbStrDup(db, pColl->zName);
}
}
pTab->iPKey = -1;
if( db->mallocFailed ){
sqlite3DeleteTable(pTab);
return 0;
}
return pTab;
}
/*
** Prepare a SELECT statement for processing by doing the following
** things:
**
** (1) Make sure VDBE cursor numbers have been assigned to every
** element of the FROM clause.
**
** (2) Fill in the pTabList->a[].pTab fields in the SrcList that
** defines FROM clause. When views appear in the FROM clause,
** fill pTabList->a[].pSelect with a copy of the SELECT statement
** that implements the view. A copy is made of the view's SELECT
** statement so that we can freely modify or delete that statement
** without worrying about messing up the presistent representation
** of the view.
**
** (3) Add terms to the WHERE clause to accomodate the NATURAL keyword
** on joins and the ON and USING clause of joins.
**
** (4) Scan the list of columns in the result set (pEList) looking
** for instances of the "*" operator or the TABLE.* operator.
** If found, expand each "*" to be every column in every table
** and TABLE.* to be every column in TABLE.
**
** Return 0 on success. If there are problems, leave an error message
** in pParse and return non-zero.
*/
static int prepSelectStmt(Parse *pParse, Select *p){
int i, j, k, rc;
SrcList *pTabList;
ExprList *pEList;
struct SrcList_item *pFrom;
sqlite3 *db = pParse->db;
if( p==0 || p->pSrc==0 || db->mallocFailed ){
return 1;
}
pTabList = p->pSrc;
pEList = p->pEList;
/* Make sure cursor numbers have been assigned to all entries in
** the FROM clause of the SELECT statement.
*/
sqlite3SrcListAssignCursors(pParse, p->pSrc);
/* Look up every table named in the FROM clause of the select. If
** an entry of the FROM clause is a subquery instead of a table or view,
** then create a transient table structure to describe the subquery.
*/
for(i=0, pFrom=pTabList->a; i<pTabList->nSrc; i++, pFrom++){
Table *pTab;
if( pFrom->pTab!=0 ){
/* This statement has already been prepared. There is no need
** to go further. */
assert( i==0 );
return 0;
}
if( pFrom->zName==0 ){
#ifndef SQLITE_OMIT_SUBQUERY
/* A sub-query in the FROM clause of a SELECT */
assert( pFrom->pSelect!=0 );
if( pFrom->zAlias==0 ){
pFrom->zAlias =
sqlite3MPrintf(db, "sqlite_subquery_%p_", (void*)pFrom->pSelect);
}
assert( pFrom->pTab==0 );
pFrom->pTab = pTab =
sqlite3ResultSetOfSelect(pParse, pFrom->zAlias, pFrom->pSelect);
if( pTab==0 ){
return 1;
}
/* The isEphem flag indicates that the Table structure has been
** dynamically allocated and may be freed at any time. In other words,
** pTab is not pointing to a persistent table structure that defines
** part of the schema. */
pTab->isEphem = 1;
#endif
}else{
/* An ordinary table or view name in the FROM clause */
assert( pFrom->pTab==0 );
pFrom->pTab = pTab =
sqlite3LocateTable(pParse,0,pFrom->zName,pFrom->zDatabase);
if( pTab==0 ){
return 1;
}
pTab->nRef++;
#if !defined(SQLITE_OMIT_VIEW) || !defined (SQLITE_OMIT_VIRTUALTABLE)
if( pTab->pSelect || IsVirtual(pTab) ){
/* We reach here if the named table is a really a view */
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
return 1;
}
/* If pFrom->pSelect!=0 it means we are dealing with a
** view within a view. The SELECT structure has already been
** copied by the outer view so we can skip the copy step here
** in the inner view.
*/
if( pFrom->pSelect==0 ){
pFrom->pSelect = sqlite3SelectDup(db, pTab->pSelect);
}
}
sqlite-amalgamation.c view on Meta::CPAN
addrAeqB =
sqlite3VdbeAddOp1(v, OP_Yield, regAddrA);
sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
}
/* Generate code to handle the case of A>B
*/
VdbeNoopComment((v, "A-gt-B subroutine"));
addrAgtB = sqlite3VdbeCurrentAddr(v);
if( op==TK_ALL || op==TK_UNION ){
sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
}
sqlite3VdbeAddOp1(v, OP_Yield, regAddrB);
sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
sqlite3VdbeAddOp2(v, OP_Goto, 0, labelCmpr);
/* This code runs once to initialize everything.
*/
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofA);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regEofB);
sqlite3VdbeAddOp2(v, OP_Gosub, regAddrA, addrSelectA);
sqlite3VdbeAddOp2(v, OP_Gosub, regAddrB, addrSelectB);
sqlite3VdbeAddOp2(v, OP_If, regEofA, addrEofA);
sqlite3VdbeAddOp2(v, OP_If, regEofB, addrEofB);
/* Implement the main merge loop
*/
sqlite3VdbeResolveLabel(v, labelCmpr);
sqlite3VdbeAddOp4(v, OP_Permutation, 0, 0, 0, (char*)aPermute, P4_INTARRAY);
sqlite3VdbeAddOp4(v, OP_Compare, destA.iMem, destB.iMem, nOrderBy,
(char*)pKeyMerge, P4_KEYINFO_HANDOFF);
sqlite3VdbeAddOp3(v, OP_Jump, addrAltB, addrAeqB, addrAgtB);
/* Release temporary registers
*/
if( regPrev ){
sqlite3ReleaseTempRange(pParse, regPrev, nOrderBy+1);
}
/* Jump to the this point in order to terminate the query.
*/
sqlite3VdbeResolveLabel(v, labelEnd);
/* Set the number of output columns
*/
if( pDest->eDest==SRT_Callback ){
Select *pFirst = pPrior;
while( pFirst->pPrior ) pFirst = pFirst->pPrior;
generateColumnNames(pParse, 0, pFirst->pEList);
}
/* Reassembly the compound query so that it will be freed correctly
** by the calling function */
if( p->pPrior ){
sqlite3SelectDelete(db, p->pPrior);
}
p->pPrior = pPrior;
/*** TBD: Insert subroutine calls to close cursors on incomplete
**** subqueries ****/
return SQLITE_OK;
}
#endif
#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
/* Forward Declarations */
static void substExprList(sqlite3*, ExprList*, int, ExprList*);
static void substSelect(sqlite3*, Select *, int, ExprList *);
/*
** Scan through the expression pExpr. Replace every reference to
** a column in table number iTable with a copy of the iColumn-th
** entry in pEList. (But leave references to the ROWID column
** unchanged.)
**
** This routine is part of the flattening procedure. A subquery
** whose result set is defined by pEList appears as entry in the
** FROM clause of a SELECT such that the VDBE cursor assigned to that
** FORM clause entry is iTable. This routine make the necessary
** changes to pExpr so that it refers directly to the source table
** of the subquery rather the result set of the subquery.
*/
static void substExpr(
sqlite3 *db, /* Report malloc errors to this connection */
Expr *pExpr, /* Expr in which substitution occurs */
int iTable, /* Table to be substituted */
ExprList *pEList /* Substitute expressions */
){
if( pExpr==0 ) return;
if( pExpr->op==TK_COLUMN && pExpr->iTable==iTable ){
if( pExpr->iColumn<0 ){
pExpr->op = TK_NULL;
}else{
Expr *pNew;
assert( pEList!=0 && pExpr->iColumn<pEList->nExpr );
assert( pExpr->pLeft==0 && pExpr->pRight==0 && pExpr->pList==0 );
pNew = pEList->a[pExpr->iColumn].pExpr;
assert( pNew!=0 );
pExpr->op = pNew->op;
assert( pExpr->pLeft==0 );
pExpr->pLeft = sqlite3ExprDup(db, pNew->pLeft);
assert( pExpr->pRight==0 );
pExpr->pRight = sqlite3ExprDup(db, pNew->pRight);
assert( pExpr->pList==0 );
pExpr->pList = sqlite3ExprListDup(db, pNew->pList);
pExpr->iTable = pNew->iTable;
pExpr->pTab = pNew->pTab;
pExpr->iColumn = pNew->iColumn;
pExpr->iAgg = pNew->iAgg;
sqlite3TokenCopy(db, &pExpr->token, &pNew->token);
sqlite3TokenCopy(db, &pExpr->span, &pNew->span);
pExpr->pSelect = sqlite3SelectDup(db, pNew->pSelect);
pExpr->flags = pNew->flags;
}
}else{
substExpr(db, pExpr->pLeft, iTable, pEList);
substExpr(db, pExpr->pRight, iTable, pEList);
substSelect(db, pExpr->pSelect, iTable, pEList);
substExprList(db, pExpr->pList, iTable, pEList);
}
}
static void substExprList(
sqlite3 *db, /* Report malloc errors here */
ExprList *pList, /* List to scan and in which to make substitutes */
int iTable, /* Table to be substituted */
ExprList *pEList /* Substitute values */
){
int i;
if( pList==0 ) return;
for(i=0; i<pList->nExpr; i++){
substExpr(db, pList->a[i].pExpr, iTable, pEList);
}
}
static void substSelect(
sqlite3 *db, /* Report malloc errors here */
Select *p, /* SELECT statement in which to make substitutions */
int iTable, /* Table to be replaced */
ExprList *pEList /* Substitute values */
sqlite-amalgamation.c view on Meta::CPAN
** (10) The subquery does not use aggregates or the outer query does not
** use LIMIT.
**
** (11) The subquery and the outer query do not both have ORDER BY clauses.
**
** (12) The subquery is not the right term of a LEFT OUTER JOIN or the
** subquery has no WHERE clause. (added by ticket #350)
**
** (13) The subquery and outer query do not both use LIMIT
**
** (14) The subquery does not use OFFSET
**
** (15) The outer query is not part of a compound select or the
** subquery does not have both an ORDER BY and a LIMIT clause.
** (See ticket #2339)
**
** (16) The outer query is not an aggregate or the subquery does
** not contain ORDER BY. (Ticket #2942) This used to not matter
** until we introduced the group_concat() function.
**
** (17) The sub-query is not a compound select, or it is a UNION ALL
** compound clause made up entirely of non-aggregate queries, and
** the parent query:
**
** * is not itself part of a compound select,
** * is not an aggregate or DISTINCT query, and
** * has no other tables or sub-selects in the FROM clause.
**
** The parent and sub-query may contain WHERE clauses. Subject to
** rules (11), (13) and (14), they may also contain ORDER BY,
** LIMIT and OFFSET clauses.
**
** (18) If the sub-query is a compound select, then all terms of the
** ORDER by clause of the parent must be simple references to
** columns of the sub-query.
**
** In this routine, the "p" parameter is a pointer to the outer query.
** The subquery is p->pSrc->a[iFrom]. isAgg is true if the outer query
** uses aggregates and subqueryIsAgg is true if the subquery uses aggregates.
**
** If flattening is not attempted, this routine is a no-op and returns 0.
** If flattening is attempted this routine returns 1.
**
** All of the expression analysis must occur on both the outer query and
** the subquery before this routine runs.
*/
static int flattenSubquery(
Parse *pParse, /* Parsing context */
Select *p, /* The parent or outer SELECT statement */
int iFrom, /* Index in p->pSrc->a[] of the inner subquery */
int isAgg, /* True if outer SELECT uses aggregate functions */
int subqueryIsAgg /* True if the subquery uses aggregate functions */
){
const char *zSavedAuthContext = pParse->zAuthContext;
Select *pParent;
Select *pSub; /* The inner query or "subquery" */
Select *pSub1; /* Pointer to the rightmost select in sub-query */
SrcList *pSrc; /* The FROM clause of the outer query */
SrcList *pSubSrc; /* The FROM clause of the subquery */
ExprList *pList; /* The result set of the outer query */
int iParent; /* VDBE cursor number of the pSub result set temp table */
int i; /* Loop counter */
Expr *pWhere; /* The WHERE clause */
struct SrcList_item *pSubitem; /* The subquery */
sqlite3 *db = pParse->db;
/* Check to see if flattening is permitted. Return 0 if not.
*/
if( p==0 ) return 0;
pSrc = p->pSrc;
assert( pSrc && iFrom>=0 && iFrom<pSrc->nSrc );
pSubitem = &pSrc->a[iFrom];
iParent = pSubitem->iCursor;
pSub = pSubitem->pSelect;
assert( pSub!=0 );
if( isAgg && subqueryIsAgg ) return 0; /* Restriction (1) */
if( subqueryIsAgg && pSrc->nSrc>1 ) return 0; /* Restriction (2) */
pSubSrc = pSub->pSrc;
assert( pSubSrc );
/* Prior to version 3.1.2, when LIMIT and OFFSET had to be simple constants,
** not arbitrary expresssions, we allowed some combining of LIMIT and OFFSET
** because they could be computed at compile-time. But when LIMIT and OFFSET
** became arbitrary expressions, we were forced to add restrictions (13)
** and (14). */
if( pSub->pLimit && p->pLimit ) return 0; /* Restriction (13) */
if( pSub->pOffset ) return 0; /* Restriction (14) */
if( p->pRightmost && pSub->pLimit && pSub->pOrderBy ){
return 0; /* Restriction (15) */
}
if( pSubSrc->nSrc==0 ) return 0; /* Restriction (7) */
if( (pSub->isDistinct || pSub->pLimit)
&& (pSrc->nSrc>1 || isAgg) ){ /* Restrictions (4)(5)(8)(9) */
return 0;
}
if( p->isDistinct && subqueryIsAgg ) return 0; /* Restriction (6) */
if( (p->disallowOrderBy || p->pOrderBy) && pSub->pOrderBy ){
return 0; /* Restriction (11) */
}
if( isAgg && pSub->pOrderBy ) return 0; /* Restriction (16) */
/* Restriction 3: If the subquery is a join, make sure the subquery is
** not used as the right operand of an outer join. Examples of why this
** is not allowed:
**
** t1 LEFT OUTER JOIN (t2 JOIN t3)
**
** If we flatten the above, we would get
**
** (t1 LEFT OUTER JOIN t2) JOIN t3
**
** which is not at all the same thing.
*/
if( pSubSrc->nSrc>1 && (pSubitem->jointype & JT_OUTER)!=0 ){
return 0;
}
/* Restriction 12: If the subquery is the right operand of a left outer
** join, make sure the subquery has no WHERE clause.
** An examples of why this is not allowed:
**
** t1 LEFT OUTER JOIN (SELECT * FROM t2 WHERE t2.x>0)
sqlite-amalgamation.c view on Meta::CPAN
if( p->pOrderBy ){
int ii;
for(ii=0; ii<p->pOrderBy->nExpr; ii++){
Expr *pExpr = p->pOrderBy->a[ii].pExpr;
if( pExpr->op!=TK_COLUMN || pExpr->iTable!=iParent ){
return 0;
}
}
}
}
pParse->zAuthContext = pSubitem->zName;
sqlite3AuthCheck(pParse, SQLITE_SELECT, 0, 0, 0);
pParse->zAuthContext = zSavedAuthContext;
/* If the sub-query is a compound SELECT statement, then it must be
** a UNION ALL and the parent query must be of the form:
**
** SELECT <expr-list> FROM (<sub-query>) <where-clause>
**
** followed by any ORDER BY, LIMIT and/or OFFSET clauses. This block
** creates N copies of the parent query without any ORDER BY, LIMIT or
** OFFSET clauses and joins them to the left-hand-side of the original
** using UNION ALL operators. In this case N is the number of simple
** select statements in the compound sub-query.
*/
for(pSub=pSub->pPrior; pSub; pSub=pSub->pPrior){
Select *pNew;
ExprList *pOrderBy = p->pOrderBy;
Expr *pLimit = p->pLimit;
Expr *pOffset = p->pOffset;
Select *pPrior = p->pPrior;
p->pOrderBy = 0;
p->pSrc = 0;
p->pPrior = 0;
p->pLimit = 0;
pNew = sqlite3SelectDup(db, p);
pNew->pPrior = pPrior;
p->pPrior = pNew;
p->pOrderBy = pOrderBy;
p->op = TK_ALL;
p->pSrc = pSrc;
p->pLimit = pLimit;
p->pOffset = pOffset;
p->pRightmost = 0;
pNew->pRightmost = 0;
}
/* If we reach this point, it means flattening is permitted for the
** iFrom-th entry of the FROM clause in the outer query.
*/
pSub = pSub1 = pSubitem->pSelect;
for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){
int nSubSrc = pSubSrc->nSrc;
int jointype = 0;
pSubSrc = pSub->pSrc;
pSrc = pParent->pSrc;
/* Move all of the FROM elements of the subquery into the
** the FROM clause of the outer query. Before doing this, remember
** the cursor number for the original outer query FROM element in
** iParent. The iParent cursor will never be used. Subsequent code
** will scan expressions looking for iParent references and replace
** those references with expressions that resolve to the subquery FROM
** elements we are now copying in.
*/
if( pSrc ){
pSubitem = &pSrc->a[iFrom];
nSubSrc = pSubSrc->nSrc;
jointype = pSubitem->jointype;
sqlite3DeleteTable(pSubitem->pTab);
sqlite3DbFree(db, pSubitem->zDatabase);
sqlite3DbFree(db, pSubitem->zName);
sqlite3DbFree(db, pSubitem->zAlias);
pSubitem->pTab = 0;
pSubitem->zDatabase = 0;
pSubitem->zName = 0;
pSubitem->zAlias = 0;
}
if( nSubSrc!=1 || !pSrc ){
int extra = nSubSrc - 1;
for(i=(pSrc?1:0); i<nSubSrc; i++){
pSrc = sqlite3SrcListAppend(db, pSrc, 0, 0);
if( pSrc==0 ){
pParent->pSrc = 0;
return 1;
}
}
pParent->pSrc = pSrc;
for(i=pSrc->nSrc-1; i-extra>=iFrom; i--){
pSrc->a[i] = pSrc->a[i-extra];
}
}
for(i=0; i<nSubSrc; i++){
pSrc->a[i+iFrom] = pSubSrc->a[i];
memset(&pSubSrc->a[i], 0, sizeof(pSubSrc->a[i]));
}
pSrc->a[iFrom].jointype = jointype;
/* Now begin substituting subquery result set expressions for
** references to the iParent in the outer query.
**
** Example:
**
** SELECT a+5, b*10 FROM (SELECT x*3 AS a, y+10 AS b FROM t1) WHERE a>b;
** \ \_____________ subquery __________/ /
** \_____________________ outer query ______________________________/
**
** We look at every expression in the outer query and every place we see
** "a" we substitute "x*3" and every place we see "b" we substitute "y+10".
*/
pList = pParent->pEList;
for(i=0; i<pList->nExpr; i++){
Expr *pExpr;
if( pList->a[i].zName==0 && (pExpr = pList->a[i].pExpr)->span.z!=0 ){
pList->a[i].zName =
sqlite3DbStrNDup(db, (char*)pExpr->span.z, pExpr->span.n);
}
}
substExprList(db, pParent->pEList, iParent, pSub->pEList);
if( isAgg ){
substExprList(db, pParent->pGroupBy, iParent, pSub->pEList);
sqlite-amalgamation.c view on Meta::CPAN
}
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
/*
** Analyze the SELECT statement passed as an argument to see if it
** is a min() or max() query. Return WHERE_ORDERBY_MIN or WHERE_ORDERBY_MAX if
** it is, or 0 otherwise. At present, a query is considered to be
** a min()/max() query if:
**
** 1. There is a single object in the FROM clause.
**
** 2. There is a single expression in the result set, and it is
** either min(x) or max(x), where x is a column reference.
*/
static int minMaxQuery(Parse *pParse, Select *p){
Expr *pExpr;
ExprList *pEList = p->pEList;
if( pEList->nExpr!=1 ) return WHERE_ORDERBY_NORMAL;
pExpr = pEList->a[0].pExpr;
pEList = pExpr->pList;
if( pExpr->op!=TK_AGG_FUNCTION || pEList==0 || pEList->nExpr!=1 ) return 0;
if( pEList->a[0].pExpr->op!=TK_AGG_COLUMN ) return WHERE_ORDERBY_NORMAL;
if( pExpr->token.n!=3 ) return WHERE_ORDERBY_NORMAL;
if( sqlite3StrNICmp((char*)pExpr->token.z,"min",3)==0 ){
return WHERE_ORDERBY_MIN;
}else if( sqlite3StrNICmp((char*)pExpr->token.z,"max",3)==0 ){
return WHERE_ORDERBY_MAX;
}
return WHERE_ORDERBY_NORMAL;
}
/*
** This routine resolves any names used in the result set of the
** supplied SELECT statement. If the SELECT statement being resolved
** is a sub-select, then pOuterNC is a pointer to the NameContext
** of the parent SELECT.
*/
SQLITE_PRIVATE int sqlite3SelectResolve(
Parse *pParse, /* The parser context */
Select *p, /* The SELECT statement being coded. */
NameContext *pOuterNC /* The outer name context. May be NULL. */
){
ExprList *pEList; /* Result set. */
int i; /* For-loop variable used in multiple places */
NameContext sNC; /* Local name-context */
ExprList *pGroupBy; /* The group by clause */
/* If this routine has run before, return immediately. */
if( p->isResolved ){
assert( !pOuterNC );
return SQLITE_OK;
}
p->isResolved = 1;
/* If there have already been errors, do nothing. */
if( pParse->nErr>0 ){
return SQLITE_ERROR;
}
/* Prepare the select statement. This call will allocate all cursors
** required to handle the tables and subqueries in the FROM clause.
*/
if( prepSelectStmt(pParse, p) ){
return SQLITE_ERROR;
}
/* Resolve the expressions in the LIMIT and OFFSET clauses. These
** are not allowed to refer to any names, so pass an empty NameContext.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
if( sqlite3ExprResolveNames(&sNC, p->pLimit) ||
sqlite3ExprResolveNames(&sNC, p->pOffset) ){
return SQLITE_ERROR;
}
/* Set up the local name-context to pass to ExprResolveNames() to
** resolve the expression-list.
*/
sNC.allowAgg = 1;
sNC.pSrcList = p->pSrc;
sNC.pNext = pOuterNC;
/* Resolve names in the result set. */
pEList = p->pEList;
if( !pEList ) return SQLITE_ERROR;
for(i=0; i<pEList->nExpr; i++){
Expr *pX = pEList->a[i].pExpr;
if( sqlite3ExprResolveNames(&sNC, pX) ){
return SQLITE_ERROR;
}
}
/* If there are no aggregate functions in the result-set, and no GROUP BY
** expression, do not allow aggregates in any of the other expressions.
*/
assert( !p->isAgg );
pGroupBy = p->pGroupBy;
if( pGroupBy || sNC.hasAgg ){
p->isAgg = 1;
}else{
sNC.allowAgg = 0;
}
/* If a HAVING clause is present, then there must be a GROUP BY clause.
*/
if( p->pHaving && !pGroupBy ){
sqlite3ErrorMsg(pParse, "a GROUP BY clause is required before HAVING");
return SQLITE_ERROR;
}
/* Add the expression list to the name-context before parsing the
** other expressions in the SELECT statement. This is so that
** expressions in the WHERE clause (etc.) can refer to expressions by
** aliases in the result set.
**
** Minor point: If this is the case, then the expression will be
** re-evaluated for each reference to it.
*/
sNC.pEList = p->pEList;
sqlite-amalgamation.c view on Meta::CPAN
** in the other SELECTs.
*/
if( p->pPrior ){
return sqlite3SelectResolve(pParse, p->pPrior, pOuterNC);
}else{
return SQLITE_OK;
}
}
/*
** Reset the aggregate accumulator.
**
** The aggregate accumulator is a set of memory cells that hold
** intermediate results while calculating an aggregate. This
** routine simply stores NULLs in all of those memory cells.
*/
static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){
Vdbe *v = pParse->pVdbe;
int i;
struct AggInfo_func *pFunc;
if( pAggInfo->nFunc+pAggInfo->nColumn==0 ){
return;
}
for(i=0; i<pAggInfo->nColumn; i++){
sqlite3VdbeAddOp2(v, OP_Null, 0, pAggInfo->aCol[i].iMem);
}
for(pFunc=pAggInfo->aFunc, i=0; i<pAggInfo->nFunc; i++, pFunc++){
sqlite3VdbeAddOp2(v, OP_Null, 0, pFunc->iMem);
if( pFunc->iDistinct>=0 ){
Expr *pE = pFunc->pExpr;
if( pE->pList==0 || pE->pList->nExpr!=1 ){
sqlite3ErrorMsg(pParse, "DISTINCT in aggregate must be followed "
"by an expression");
pFunc->iDistinct = -1;
}else{
KeyInfo *pKeyInfo = keyInfoFromExprList(pParse, pE->pList);
sqlite3VdbeAddOp4(v, OP_OpenEphemeral, pFunc->iDistinct, 0, 0,
(char*)pKeyInfo, P4_KEYINFO_HANDOFF);
}
}
}
}
/*
** Invoke the OP_AggFinalize opcode for every aggregate function
** in the AggInfo structure.
*/
static void finalizeAggFunctions(Parse *pParse, AggInfo *pAggInfo){
Vdbe *v = pParse->pVdbe;
int i;
struct AggInfo_func *pF;
for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
ExprList *pList = pF->pExpr->pList;
sqlite3VdbeAddOp4(v, OP_AggFinal, pF->iMem, pList ? pList->nExpr : 0, 0,
(void*)pF->pFunc, P4_FUNCDEF);
}
}
/*
** Update the accumulator memory cells for an aggregate based on
** the current cursor position.
*/
static void updateAccumulator(Parse *pParse, AggInfo *pAggInfo){
Vdbe *v = pParse->pVdbe;
int i;
struct AggInfo_func *pF;
struct AggInfo_col *pC;
pAggInfo->directMode = 1;
for(i=0, pF=pAggInfo->aFunc; i<pAggInfo->nFunc; i++, pF++){
int nArg;
int addrNext = 0;
int regAgg;
ExprList *pList = pF->pExpr->pList;
if( pList ){
nArg = pList->nExpr;
regAgg = sqlite3GetTempRange(pParse, nArg);
sqlite3ExprCodeExprList(pParse, pList, regAgg, 0);
}else{
nArg = 0;
regAgg = 0;
}
if( pF->iDistinct>=0 ){
addrNext = sqlite3VdbeMakeLabel(v);
assert( nArg==1 );
codeDistinct(pParse, pF->iDistinct, addrNext, 1, regAgg);
}
if( pF->pFunc->needCollSeq ){
CollSeq *pColl = 0;
struct ExprList_item *pItem;
int j;
assert( pList!=0 ); /* pList!=0 if pF->pFunc->needCollSeq is true */
for(j=0, pItem=pList->a; !pColl && j<nArg; j++, pItem++){
pColl = sqlite3ExprCollSeq(pParse, pItem->pExpr);
}
if( !pColl ){
pColl = pParse->db->pDfltColl;
}
sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ);
}
sqlite3VdbeAddOp4(v, OP_AggStep, 0, regAgg, pF->iMem,
(void*)pF->pFunc, P4_FUNCDEF);
sqlite3VdbeChangeP5(v, nArg);
sqlite3ReleaseTempRange(pParse, regAgg, nArg);
sqlite3ExprCacheAffinityChange(pParse, regAgg, nArg);
if( addrNext ){
sqlite3VdbeResolveLabel(v, addrNext);
}
}
for(i=0, pC=pAggInfo->aCol; i<pAggInfo->nAccumulator; i++, pC++){
sqlite3ExprCode(pParse, pC->pExpr, pC->iMem);
}
pAggInfo->directMode = 0;
}
/*
** Generate code for the given SELECT statement.
**
** The results are distributed in various ways depending on the
** contents of the SelectDest structure pointed to by argument pDest
** as follows:
**
** pDest->eDest Result
** ------------ -------------------------------------------
** SRT_Callback Invoke the callback for each row of the result.
**
** SRT_Mem Store first result in memory cell pDest->iParm
**
** SRT_Set Store results as keys of table pDest->iParm.
** Apply the affinity pDest->affinity before storing them.
**
** SRT_Union Store results as a key in a temporary table pDest->iParm.
**
** SRT_Except Remove results from the temporary table pDest->iParm.
**
** SRT_Table Store results in temporary table pDest->iParm
**
** SRT_EphemTab Create an temporary table pDest->iParm and store
** the result there. The cursor is left open after
** returning.
**
** SRT_Coroutine Invoke a co-routine to compute a single row of
** the result
**
** SRT_Exists Store a 1 in memory cell pDest->iParm if the result
** set is not empty.
**
** SRT_Discard Throw the results away.
**
** See the selectInnerLoop() function for a canonical listing of the
** allowed values of eDest and their meanings.
**
** This routine returns the number of errors. If any errors are
** encountered, then an appropriate error message is left in
** pParse->zErrMsg.
**
** This routine does NOT free the Select structure passed in. The
** calling function needs to do that.
**
** The pParent, parentTab, and *pParentAgg fields are filled in if this
** SELECT is a subquery. This routine may try to combine this SELECT
** with its parent to form a single flat query. In so doing, it might
** change the parent query from a non-aggregate to an aggregate query.
** For that reason, the pParentAgg flag is passed as a pointer, so it
** can be changed.
**
** Example 1: The meaning of the pParent parameter.
**
** SELECT * FROM t1 JOIN (SELECT x, count(*) FROM t2) JOIN t3;
** \ \_______ subquery _______/ /
** \ /
** \____________________ outer query ___________________/
**
** This routine is called for the outer query first. For that call,
** pParent will be NULL. During the processing of the outer query, this
** routine is called recursively to handle the subquery. For the recursive
** call, pParent will point to the outer query. Because the subquery is
** the second element in a three-way join, the parentTab parameter will
** be 1 (the 2nd value of a 0-indexed array.)
*/
SQLITE_PRIVATE int sqlite3Select(
Parse *pParse, /* The parser context */
Select *p, /* The SELECT statement being coded. */
SelectDest *pDest, /* What to do with the query results */
Select *pParent, /* Another SELECT for which this is a sub-query */
int parentTab, /* Index in pParent->pSrc of this query */
int *pParentAgg /* True if pParent uses aggregate functions */
){
int i, j; /* Loop counters */
WhereInfo *pWInfo; /* Return from sqlite3WhereBegin() */
Vdbe *v; /* The virtual machine under construction */
int isAgg; /* True for select lists like "count(*)" */
ExprList *pEList; /* List of columns to extract. */
SrcList *pTabList; /* List of tables to select from */
Expr *pWhere; /* The WHERE clause. May be NULL */
ExprList *pOrderBy; /* The ORDER BY clause. May be NULL */
ExprList *pGroupBy; /* The GROUP BY clause. May be NULL */
Expr *pHaving; /* The HAVING clause. May be NULL */
int isDistinct; /* True if the DISTINCT keyword is present */
sqlite-amalgamation.c view on Meta::CPAN
switch( pTriggerStep->op ){
case TK_SELECT: {
Select *ss = sqlite3SelectDup(db, pTriggerStep->pSelect);
if( ss ){
SelectDest dest;
sqlite3SelectDestInit(&dest, SRT_Discard, 0);
sqlite3SelectResolve(pParse, ss, 0);
sqlite3Select(pParse, ss, &dest, 0, 0, 0);
sqlite3SelectDelete(db, ss);
}
break;
}
case TK_UPDATE: {
SrcList *pSrc;
pSrc = targetSrcList(pParse, pTriggerStep);
sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
sqlite3Update(pParse, pSrc,
sqlite3ExprListDup(db, pTriggerStep->pExprList),
sqlite3ExprDup(db, pTriggerStep->pWhere), orconf);
sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
break;
}
case TK_INSERT: {
SrcList *pSrc;
pSrc = targetSrcList(pParse, pTriggerStep);
sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
sqlite3Insert(pParse, pSrc,
sqlite3ExprListDup(db, pTriggerStep->pExprList),
sqlite3SelectDup(db, pTriggerStep->pSelect),
sqlite3IdListDup(db, pTriggerStep->pIdList), orconf);
sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
break;
}
case TK_DELETE: {
SrcList *pSrc;
sqlite3VdbeAddOp2(v, OP_ResetCount, 0, 0);
pSrc = targetSrcList(pParse, pTriggerStep);
sqlite3DeleteFrom(pParse, pSrc,
sqlite3ExprDup(db, pTriggerStep->pWhere));
sqlite3VdbeAddOp2(v, OP_ResetCount, 1, 0);
break;
}
default:
assert(0);
}
pTriggerStep = pTriggerStep->pNext;
}
sqlite3VdbeAddOp2(v, OP_ContextPop, 0, 0);
VdbeComment((v, "end trigger %s", pStepList->pTrig->name));
return 0;
}
/*
** This is called to code FOR EACH ROW triggers.
**
** When the code that this function generates is executed, the following
** must be true:
**
** 1. No cursors may be open in the main database. (But newIdx and oldIdx
** can be indices of cursors in temporary tables. See below.)
**
** 2. If the triggers being coded are ON INSERT or ON UPDATE triggers, then
** a temporary vdbe cursor (index newIdx) must be open and pointing at
** a row containing values to be substituted for new.* expressions in the
** trigger program(s).
**
** 3. If the triggers being coded are ON DELETE or ON UPDATE triggers, then
** a temporary vdbe cursor (index oldIdx) must be open and pointing at
** a row containing values to be substituted for old.* expressions in the
** trigger program(s).
**
** If they are not NULL, the piOldColMask and piNewColMask output variables
** are set to values that describe the columns used by the trigger program
** in the OLD.* and NEW.* tables respectively. If column N of the
** pseudo-table is read at least once, the corresponding bit of the output
** mask is set. If a column with an index greater than 32 is read, the
** output mask is set to the special value 0xffffffff.
**
*/
SQLITE_PRIVATE int sqlite3CodeRowTrigger(
Parse *pParse, /* Parse context */
int op, /* One of TK_UPDATE, TK_INSERT, TK_DELETE */
ExprList *pChanges, /* Changes list for any UPDATE OF triggers */
int tr_tm, /* One of TRIGGER_BEFORE, TRIGGER_AFTER */
Table *pTab, /* The table to code triggers from */
int newIdx, /* The indice of the "new" row to access */
int oldIdx, /* The indice of the "old" row to access */
int orconf, /* ON CONFLICT policy */
int ignoreJump, /* Instruction to jump to for RAISE(IGNORE) */
u32 *piOldColMask, /* OUT: Mask of columns used from the OLD.* table */
u32 *piNewColMask /* OUT: Mask of columns used from the NEW.* table */
){
Trigger *p;
sqlite3 *db = pParse->db;
TriggerStack trigStackEntry;
trigStackEntry.oldColMask = 0;
trigStackEntry.newColMask = 0;
assert(op == TK_UPDATE || op == TK_INSERT || op == TK_DELETE);
assert(tr_tm == TRIGGER_BEFORE || tr_tm == TRIGGER_AFTER );
assert(newIdx != -1 || oldIdx != -1);
for(p=pTab->pTrigger; p; p=p->pNext){
int fire_this = 0;
/* Determine whether we should code this trigger */
if(
p->op==op &&
p->tr_tm==tr_tm &&
(p->pSchema==p->pTabSchema || p->pSchema==db->aDb[1].pSchema) &&
(op!=TK_UPDATE||!p->pColumns||checkColumnOverLap(p->pColumns,pChanges))
){
TriggerStack *pS; /* Pointer to trigger-stack entry */
for(pS=pParse->trigStack; pS && p!=pS->pTrigger; pS=pS->pNext){}
if( !pS ){
fire_this = 1;
}
#if 0 /* Give no warning for recursive triggers. Just do not do them */
else{
sqlite3ErrorMsg(pParse, "recursive triggers not supported (%s)",
p->name);
return SQLITE_ERROR;
}
#endif
}
sqlite-amalgamation.c view on Meta::CPAN
int okOnePass; /* True for one-pass algorithm without the FIFO */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
int triggers_exist = 0; /* True if any row triggers exist */
#endif
int iBeginAfterTrigger; /* Address of after trigger program */
int iEndAfterTrigger; /* Exit of after trigger program */
int iBeginBeforeTrigger; /* Address of before trigger program */
int iEndBeforeTrigger; /* Exit of before trigger program */
u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
u32 new_col_mask = 0; /* Mask of NEW.* columns in use */
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regData; /* New data for the row */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto update_cleanup;
}
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* If there are FOR EACH ROW triggers, allocate cursors for the
** special OLD and NEW tables
*/
if( triggers_exist ){
newIdx = pParse->nTab++;
oldIdx = pParse->nTab++;
}
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ExprResolveNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
/* Allocate memory for the array aRegIdx[]. There is one entry in the
** array for each index associated with table being updated. Fill in
** the value with a register number for indices that are to be used
** and with zero for unused indices.
sqlite-amalgamation.c view on Meta::CPAN
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView && !IsVirtual(pTab) ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Jump back to this point if a trigger encounters an IGNORE constraint. */
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
/* Top of the update loop */
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp2(v, OP_FifoRead, regOldRowid, 0);
}
if( triggers_exist ){
int regRowid;
int regRow;
int regCols;
/* Make cursor iCur point to the record that is being updated.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* Generate the OLD table
*/
regRowid = sqlite3GetTempReg(pParse);
regRow = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
if( !old_col_mask ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regRow);
}else{
sqlite3VdbeAddOp2(v, OP_RowData, iCur, regRow);
}
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, regRow, regRowid);
/* Generate the NEW table
*/
if( chngRowid ){
sqlite3ExprCodeAndCache(pParse, pRowidExpr, regRowid);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
}
regCols = sqlite3GetTempRange(pParse, pTab->nCol);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
continue;
}
j = aXRef[i];
if( new_col_mask&((u32)1<<i) || new_col_mask==0xffffffff ){
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regCols+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr, regCols+i);
}
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
}
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRow);
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
sqlite3ExprCacheAffinityChange(pParse, regCols, pTab->nCol);
}
sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
/* if( pParse->nErr ) goto update_cleanup; */
sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRow, regRowid);
sqlite3ReleaseTempReg(pParse, regRowid);
sqlite3ReleaseTempReg(pParse, regRow);
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
}
if( !isView && !IsVirtual(pTab) ){
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regData+i);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regData+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regData+i);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
/* If changing the record number, delete the old record.
*/
if( chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1, -1, 0);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
/* If there are triggers, close all the cursors after each iteration
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp2(v, OP_Close, oldIdx, 0);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", P4_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Generate code for an UPDATE of a virtual table.
**
** The strategy is that we create an ephemerial table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row. (note1)
** (C) The content of every column in the row.
**
** Then we loop over this ephemeral table and for each row in
** the ephermeral table call VUpdate.
**
sqlite-amalgamation.c view on Meta::CPAN
/************** Begin file where.c *******************************************/
/*
** 2001 September 15
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements. This module is responsible for
** generating the code that loops through a table looking for applicable
** rows. Indices are selected and used to speed the search when doing
** so is applicable. Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.319 2008/08/01 17:37:41 danielk1977 Exp $
*/
/*
** The number of bits in a Bitmask. "BMS" means "BitMask Size".
*/
#define BMS (sizeof(Bitmask)*8)
/*
** Trace output macros
*/
#if defined(SQLITE_TEST) || defined(SQLITE_DEBUG)
SQLITE_PRIVATE int sqlite3WhereTrace = 0;
#endif
#if 0
# define WHERETRACE(X) if(sqlite3WhereTrace) sqlite3DebugPrintf X
#else
# define WHERETRACE(X)
#endif
/* Forward reference
*/
typedef struct WhereClause WhereClause;
typedef struct ExprMaskSet ExprMaskSet;
/*
** The query generator uses an array of instances of this structure to
** help it analyze the subexpressions of the WHERE clause. Each WHERE
** clause subexpression is separated from the others by an AND operator.
**
** All WhereTerms are collected into a single WhereClause structure.
** The following identity holds:
**
** WhereTerm.pWC->a[WhereTerm.idx] == WhereTerm
**
** When a term is of the form:
**
** X <op> <expr>
**
** where X is a column name and <op> is one of certain operators,
** then WhereTerm.leftCursor and WhereTerm.leftColumn record the
** cursor number and column number for X. WhereTerm.operator records
** the <op> using a bitmask encoding defined by WO_xxx below. The
** use of a bitmask encoding for the operator allows us to search
** quickly for terms that match any of several different operators.
**
** prereqRight and prereqAll record sets of cursor numbers,
** but they do so indirectly. A single ExprMaskSet structure translates
** cursor number into bits and the translated bit is stored in the prereq
** fields. The translation is used in order to maximize the number of
** bits that will fit in a Bitmask. The VDBE cursor numbers might be
** spread out over the non-negative integers. For example, the cursor
** numbers might be 3, 8, 9, 10, 20, 23, 41, and 45. The ExprMaskSet
** translates these sparse cursor numbers into consecutive integers
** beginning with 0 in order to make the best possible use of the available
** bits in the Bitmask. So, in the example above, the cursor numbers
** would be mapped into integers 0 through 7.
*/
typedef struct WhereTerm WhereTerm;
struct WhereTerm {
Expr *pExpr; /* Pointer to the subexpression */
i16 iParent; /* Disable pWC->a[iParent] when this term disabled */
i16 leftCursor; /* Cursor number of X in "X <op> <expr>" */
i16 leftColumn; /* Column number of X in "X <op> <expr>" */
u16 eOperator; /* A WO_xx value describing <op> */
u8 flags; /* Bit flags. See below */
u8 nChild; /* Number of children that must disable us */
WhereClause *pWC; /* The clause this term is part of */
Bitmask prereqRight; /* Bitmask of tables used by pRight */
Bitmask prereqAll; /* Bitmask of tables referenced by p */
};
/*
** Allowed values of WhereTerm.flags
*/
#define TERM_DYNAMIC 0x01 /* Need to call sqlite3ExprDelete(db, pExpr) */
#define TERM_VIRTUAL 0x02 /* Added by the optimizer. Do not code */
#define TERM_CODED 0x04 /* This term is already coded */
#define TERM_COPIED 0x08 /* Has a child */
#define TERM_OR_OK 0x10 /* Used during OR-clause processing */
/*
** An instance of the following structure holds all information about a
** WHERE clause. Mostly this is a container for one or more WhereTerms.
*/
struct WhereClause {
Parse *pParse; /* The parser context */
ExprMaskSet *pMaskSet; /* Mapping of table indices to bitmasks */
int nTerm; /* Number of terms */
int nSlot; /* Number of entries in a[] */
WhereTerm *a; /* Each a[] describes a term of the WHERE cluase */
WhereTerm aStatic[10]; /* Initial static space for a[] */
};
/*
** An instance of the following structure keeps track of a mapping
** between VDBE cursor numbers and bits of the bitmasks in WhereTerm.
**
** The VDBE cursor numbers are small integers contained in
** SrcList_item.iCursor and Expr.iTable fields. For any given WHERE
** clause, the cursor numbers might not begin with 0 and they might
** contain gaps in the numbering sequence. But we want to make maximum
** use of the bits in our bitmasks. This structure provides a mapping
** from the sparse cursor numbers into consecutive integers beginning
** with 0.
**
** If ExprMaskSet.ix[A]==B it means that The A-th bit of a Bitmask
** corresponds VDBE cursor number B. The A-th bit of a bitmask is 1<<A.
**
** For example, if the WHERE clause expression used these VDBE
** cursors: 4, 5, 8, 29, 57, 73. Then the ExprMaskSet structure
** would map those cursor numbers into bits 0 through 5.
**
** Note that the mapping is not necessarily ordered. In the example
** above, the mapping might go like this: 4->3, 5->1, 8->2, 29->0,
** 57->5, 73->4. Or one of 719 other combinations might be used. It
** does not really matter. What is important is that sparse cursor
** numbers all get mapped into bit numbers that begin with 0 and contain
** no gaps.
*/
struct ExprMaskSet {
int n; /* Number of assigned cursor values */
int ix[sizeof(Bitmask)*8]; /* Cursor assigned to each bit */
};
/*
** Bitmasks for the operators that indices are able to exploit. An
** OR-ed combination of these values can be used when searching for
** terms in the where clause.
*/
#define WO_IN 1
#define WO_EQ 2
#define WO_LT (WO_EQ<<(TK_LT-TK_EQ))
#define WO_LE (WO_EQ<<(TK_LE-TK_EQ))
#define WO_GT (WO_EQ<<(TK_GT-TK_EQ))
#define WO_GE (WO_EQ<<(TK_GE-TK_EQ))
#define WO_MATCH 64
#define WO_ISNULL 128
/*
** Value for flags returned by bestIndex().
**
** The least significant byte is reserved as a mask for WO_ values above.
** The WhereLevel.flags field is usually set to WO_IN|WO_EQ|WO_ISNULL.
** But if the table is the right table of a left join, WhereLevel.flags
** is set to WO_IN|WO_EQ. The WhereLevel.flags field can then be used as
** the "op" parameter to findTerm when we are resolving equality constraints.
** ISNULL constraints will then not be used on the right table of a left
** join. Tickets #2177 and #2189.
*/
#define WHERE_ROWID_EQ 0x000100 /* rowid=EXPR or rowid IN (...) */
#define WHERE_ROWID_RANGE 0x000200 /* rowid<EXPR and/or rowid>EXPR */
#define WHERE_COLUMN_EQ 0x001000 /* x=EXPR or x IN (...) */
#define WHERE_COLUMN_RANGE 0x002000 /* x<EXPR and/or x>EXPR */
#define WHERE_COLUMN_IN 0x004000 /* x IN (...) */
#define WHERE_TOP_LIMIT 0x010000 /* x<EXPR or x<=EXPR constraint */
#define WHERE_BTM_LIMIT 0x020000 /* x>EXPR or x>=EXPR constraint */
#define WHERE_IDX_ONLY 0x080000 /* Use index only - omit table */
#define WHERE_ORDERBY 0x100000 /* Output will appear in correct order */
#define WHERE_REVERSE 0x200000 /* Scan in reverse order */
#define WHERE_UNIQUE 0x400000 /* Selects no more than one row */
#define WHERE_VIRTUALTABLE 0x800000 /* Use virtual-table processing */
/*
** Initialize a preallocated WhereClause structure.
*/
static void whereClauseInit(
WhereClause *pWC, /* The WhereClause to be initialized */
Parse *pParse, /* The parsing context */
ExprMaskSet *pMaskSet /* Mapping from table indices to bitmasks */
){
pWC->pParse = pParse;
pWC->pMaskSet = pMaskSet;
pWC->nTerm = 0;
pWC->nSlot = ArraySize(pWC->aStatic);
pWC->a = pWC->aStatic;
}
/*
** Deallocate a WhereClause structure. The WhereClause structure
** itself is not freed. This routine is the inverse of whereClauseInit().
sqlite-amalgamation.c view on Meta::CPAN
int idx;
if( pWC->nTerm>=pWC->nSlot ){
WhereTerm *pOld = pWC->a;
sqlite3 *db = pWC->pParse->db;
pWC->a = sqlite3DbMallocRaw(db, sizeof(pWC->a[0])*pWC->nSlot*2 );
if( pWC->a==0 ){
if( flags & TERM_DYNAMIC ){
sqlite3ExprDelete(db, p);
}
pWC->a = pOld;
return 0;
}
memcpy(pWC->a, pOld, sizeof(pWC->a[0])*pWC->nTerm);
if( pOld!=pWC->aStatic ){
sqlite3DbFree(db, pOld);
}
pWC->nSlot *= 2;
}
pTerm = &pWC->a[idx = pWC->nTerm];
pWC->nTerm++;
pTerm->pExpr = p;
pTerm->flags = flags;
pTerm->pWC = pWC;
pTerm->iParent = -1;
return idx;
}
/*
** This routine identifies subexpressions in the WHERE clause where
** each subexpression is separated by the AND operator or some other
** operator specified in the op parameter. The WhereClause structure
** is filled with pointers to subexpressions. For example:
**
** WHERE a=='hello' AND coalesce(b,11)<10 AND (c+12!=d OR c==22)
** \________/ \_______________/ \________________/
** slot[0] slot[1] slot[2]
**
** The original WHERE clause in pExpr is unaltered. All this routine
** does is make slot[] entries point to substructure within pExpr.
**
** In the previous sentence and in the diagram, "slot[]" refers to
** the WhereClause.a[] array. This array grows as needed to contain
** all terms of the WHERE clause.
*/
static void whereSplit(WhereClause *pWC, Expr *pExpr, int op){
if( pExpr==0 ) return;
if( pExpr->op!=op ){
whereClauseInsert(pWC, pExpr, 0);
}else{
whereSplit(pWC, pExpr->pLeft, op);
whereSplit(pWC, pExpr->pRight, op);
}
}
/*
** Initialize an expression mask set
*/
#define initMaskSet(P) memset(P, 0, sizeof(*P))
/*
** Return the bitmask for the given cursor number. Return 0 if
** iCursor is not in the set.
*/
static Bitmask getMask(ExprMaskSet *pMaskSet, int iCursor){
int i;
for(i=0; i<pMaskSet->n; i++){
if( pMaskSet->ix[i]==iCursor ){
return ((Bitmask)1)<<i;
}
}
return 0;
}
/*
** Create a new mask for cursor iCursor.
**
** There is one cursor per table in the FROM clause. The number of
** tables in the FROM clause is limited by a test early in the
** sqlite3WhereBegin() routine. So we know that the pMaskSet->ix[]
** array will never overflow.
*/
static void createMask(ExprMaskSet *pMaskSet, int iCursor){
assert( pMaskSet->n < ArraySize(pMaskSet->ix) );
pMaskSet->ix[pMaskSet->n++] = iCursor;
}
/*
** This routine walks (recursively) an expression tree and generates
** a bitmask indicating which tables are used in that expression
** tree.
**
** In order for this routine to work, the calling function must have
** previously invoked sqlite3ExprResolveNames() on the expression. See
** the header comment on that routine for additional information.
** The sqlite3ExprResolveNames() routines looks for column names and
** sets their opcodes to TK_COLUMN and their Expr.iTable fields to
** the VDBE cursor number of the table. This routine just has to
** translate the cursor numbers into bitmask values and OR all
** the bitmasks together.
*/
static Bitmask exprListTableUsage(ExprMaskSet*, ExprList*);
static Bitmask exprSelectTableUsage(ExprMaskSet*, Select*);
static Bitmask exprTableUsage(ExprMaskSet *pMaskSet, Expr *p){
Bitmask mask = 0;
if( p==0 ) return 0;
if( p->op==TK_COLUMN ){
mask = getMask(pMaskSet, p->iTable);
return mask;
}
mask = exprTableUsage(pMaskSet, p->pRight);
mask |= exprTableUsage(pMaskSet, p->pLeft);
mask |= exprListTableUsage(pMaskSet, p->pList);
mask |= exprSelectTableUsage(pMaskSet, p->pSelect);
return mask;
}
static Bitmask exprListTableUsage(ExprMaskSet *pMaskSet, ExprList *pList){
int i;
Bitmask mask = 0;
if( pList ){
for(i=0; i<pList->nExpr; i++){
mask |= exprTableUsage(pMaskSet, pList->a[i].pExpr);
}
}
return mask;
}
static Bitmask exprSelectTableUsage(ExprMaskSet *pMaskSet, Select *pS){
Bitmask mask = 0;
while( pS ){
mask |= exprListTableUsage(pMaskSet, pS->pEList);
mask |= exprListTableUsage(pMaskSet, pS->pGroupBy);
mask |= exprListTableUsage(pMaskSet, pS->pOrderBy);
mask |= exprTableUsage(pMaskSet, pS->pWhere);
mask |= exprTableUsage(pMaskSet, pS->pHaving);
pS = pS->pPrior;
}
return mask;
}
/*
** Return TRUE if the given operator is one of the operators that is
** allowed for an indexable WHERE clause term. The allowed operators are
** "=", "<", ">", "<=", ">=", and "IN".
*/
static int allowedOp(int op){
assert( TK_GT>TK_EQ && TK_GT<TK_GE );
assert( TK_LT>TK_EQ && TK_LT<TK_GE );
assert( TK_LE>TK_EQ && TK_LE<TK_GE );
assert( TK_GE==TK_EQ+4 );
return op==TK_IN || (op>=TK_EQ && op<=TK_GE) || op==TK_ISNULL;
}
/*
** Swap two objects of type T.
*/
#define SWAP(TYPE,A,B) {TYPE t=A; A=B; B=t;}
/*
** Commute a comparison operator. Expressions of the form "X op Y"
sqlite-amalgamation.c view on Meta::CPAN
int idxNew;
Expr *pRight, *pLeft;
WhereTerm *pNewTerm;
Bitmask prereqColumn, prereqExpr;
pRight = pExpr->pList->a[0].pExpr;
pLeft = pExpr->pList->a[1].pExpr;
prereqExpr = exprTableUsage(pMaskSet, pRight);
prereqColumn = exprTableUsage(pMaskSet, pLeft);
if( (prereqExpr & prereqColumn)==0 ){
Expr *pNewExpr;
pNewExpr = sqlite3Expr(db, TK_MATCH, 0, sqlite3ExprDup(db, pRight), 0);
idxNew = whereClauseInsert(pWC, pNewExpr, TERM_VIRTUAL|TERM_DYNAMIC);
pNewTerm = &pWC->a[idxNew];
pNewTerm->prereqRight = prereqExpr;
pNewTerm->leftCursor = pLeft->iTable;
pNewTerm->leftColumn = pLeft->iColumn;
pNewTerm->eOperator = WO_MATCH;
pNewTerm->iParent = idxTerm;
pTerm = &pWC->a[idxTerm];
pTerm->nChild = 1;
pTerm->flags |= TERM_COPIED;
pNewTerm->prereqAll = pTerm->prereqAll;
}
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
/* Prevent ON clause terms of a LEFT JOIN from being used to drive
** an index for tables to the left of the join.
*/
pTerm->prereqRight |= extraRight;
}
/*
** Return TRUE if any of the expressions in pList->a[iFirst...] contain
** a reference to any table other than the iBase table.
*/
static int referencesOtherTables(
ExprList *pList, /* Search expressions in ths list */
ExprMaskSet *pMaskSet, /* Mapping from tables to bitmaps */
int iFirst, /* Be searching with the iFirst-th expression */
int iBase /* Ignore references to this table */
){
Bitmask allowed = ~getMask(pMaskSet, iBase);
while( iFirst<pList->nExpr ){
if( (exprTableUsage(pMaskSet, pList->a[iFirst++].pExpr)&allowed)!=0 ){
return 1;
}
}
return 0;
}
/*
** This routine decides if pIdx can be used to satisfy the ORDER BY
** clause. If it can, it returns 1. If pIdx cannot satisfy the
** ORDER BY clause, this routine returns 0.
**
** pOrderBy is an ORDER BY clause from a SELECT statement. pTab is the
** left-most table in the FROM clause of that same SELECT statement and
** the table has a cursor number of "base". pIdx is an index on pTab.
**
** nEqCol is the number of columns of pIdx that are used as equality
** constraints. Any of these columns may be missing from the ORDER BY
** clause and the match can still be a success.
**
** All terms of the ORDER BY that match against the index must be either
** ASC or DESC. (Terms of the ORDER BY clause past the end of a UNIQUE
** index do not need to satisfy this constraint.) The *pbRev value is
** set to 1 if the ORDER BY clause is all DESC and it is set to 0 if
** the ORDER BY clause is all ASC.
*/
static int isSortingIndex(
Parse *pParse, /* Parsing context */
ExprMaskSet *pMaskSet, /* Mapping from table indices to bitmaps */
Index *pIdx, /* The index we are testing */
int base, /* Cursor number for the table to be sorted */
ExprList *pOrderBy, /* The ORDER BY clause */
int nEqCol, /* Number of index columns with == constraints */
int *pbRev /* Set to 1 if ORDER BY is DESC */
){
int i, j; /* Loop counters */
int sortOrder = 0; /* XOR of index and ORDER BY sort direction */
int nTerm; /* Number of ORDER BY terms */
struct ExprList_item *pTerm; /* A term of the ORDER BY clause */
sqlite3 *db = pParse->db;
assert( pOrderBy!=0 );
nTerm = pOrderBy->nExpr;
assert( nTerm>0 );
/* Match terms of the ORDER BY clause against columns of
** the index.
**
** Note that indices have pIdx->nColumn regular columns plus
** one additional column containing the rowid. The rowid column
** of the index is also allowed to match against the ORDER BY
** clause.
*/
for(i=j=0, pTerm=pOrderBy->a; j<nTerm && i<=pIdx->nColumn; i++){
Expr *pExpr; /* The expression of the ORDER BY pTerm */
CollSeq *pColl; /* The collating sequence of pExpr */
int termSortOrder; /* Sort order for this term */
int iColumn; /* The i-th column of the index. -1 for rowid */
int iSortOrder; /* 1 for DESC, 0 for ASC on the i-th index term */
const char *zColl; /* Name of the collating sequence for i-th index term */
pExpr = pTerm->pExpr;
if( pExpr->op!=TK_COLUMN || pExpr->iTable!=base ){
/* Can not use an index sort on anything that is not a column in the
** left-most table of the FROM clause */
break;
}
pColl = sqlite3ExprCollSeq(pParse, pExpr);
if( !pColl ){
pColl = db->pDfltColl;
}
if( i<pIdx->nColumn ){
iColumn = pIdx->aiColumn[i];
if( iColumn==pIdx->pTable->iPKey ){
iColumn = -1;
sqlite-amalgamation.c view on Meta::CPAN
*/
#if !defined(SQLITE_OMIT_VIRTUALTABLE) && defined(SQLITE_DEBUG)
static void TRACE_IDX_INPUTS(sqlite3_index_info *p){
int i;
if( !sqlite3WhereTrace ) return;
for(i=0; i<p->nConstraint; i++){
sqlite3DebugPrintf(" constraint[%d]: col=%d termid=%d op=%d usabled=%d\n",
i,
p->aConstraint[i].iColumn,
p->aConstraint[i].iTermOffset,
p->aConstraint[i].op,
p->aConstraint[i].usable);
}
for(i=0; i<p->nOrderBy; i++){
sqlite3DebugPrintf(" orderby[%d]: col=%d desc=%d\n",
i,
p->aOrderBy[i].iColumn,
p->aOrderBy[i].desc);
}
}
static void TRACE_IDX_OUTPUTS(sqlite3_index_info *p){
int i;
if( !sqlite3WhereTrace ) return;
for(i=0; i<p->nConstraint; i++){
sqlite3DebugPrintf(" usage[%d]: argvIdx=%d omit=%d\n",
i,
p->aConstraintUsage[i].argvIndex,
p->aConstraintUsage[i].omit);
}
sqlite3DebugPrintf(" idxNum=%d\n", p->idxNum);
sqlite3DebugPrintf(" idxStr=%s\n", p->idxStr);
sqlite3DebugPrintf(" orderByConsumed=%d\n", p->orderByConsumed);
sqlite3DebugPrintf(" estimatedCost=%g\n", p->estimatedCost);
}
#else
#define TRACE_IDX_INPUTS(A)
#define TRACE_IDX_OUTPUTS(A)
#endif
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Compute the best index for a virtual table.
**
** The best index is computed by the xBestIndex method of the virtual
** table module. This routine is really just a wrapper that sets up
** the sqlite3_index_info structure that is used to communicate with
** xBestIndex.
**
** In a join, this routine might be called multiple times for the
** same virtual table. The sqlite3_index_info structure is created
** and initialized on the first invocation and reused on all subsequent
** invocations. The sqlite3_index_info structure is also used when
** code is generated to access the virtual table. The whereInfoDelete()
** routine takes care of freeing the sqlite3_index_info structure after
** everybody has finished with it.
*/
static double bestVirtualIndex(
Parse *pParse, /* The parsing context */
WhereClause *pWC, /* The WHERE clause */
struct SrcList_item *pSrc, /* The FROM clause term to search */
Bitmask notReady, /* Mask of cursors that are not available */
ExprList *pOrderBy, /* The order by clause */
int orderByUsable, /* True if we can potential sort */
sqlite3_index_info **ppIdxInfo /* Index information passed to xBestIndex */
){
Table *pTab = pSrc->pTab;
sqlite3_vtab *pVtab = pTab->pVtab;
sqlite3_index_info *pIdxInfo;
struct sqlite3_index_constraint *pIdxCons;
struct sqlite3_index_orderby *pIdxOrderBy;
struct sqlite3_index_constraint_usage *pUsage;
WhereTerm *pTerm;
int i, j;
int nOrderBy;
int rc;
/* If the sqlite3_index_info structure has not been previously
** allocated and initialized for this virtual table, then allocate
** and initialize it now
*/
pIdxInfo = *ppIdxInfo;
if( pIdxInfo==0 ){
WhereTerm *pTerm;
int nTerm;
WHERETRACE(("Recomputing index info for %s...\n", pTab->zName));
/* Count the number of possible WHERE clause constraints referring
** to this virtual table */
for(i=nTerm=0, pTerm=pWC->a; i<pWC->nTerm; i++, pTerm++){
if( pTerm->leftCursor != pSrc->iCursor ) continue;
if( (pTerm->eOperator&(pTerm->eOperator-1))==0 );
testcase( pTerm->eOperator==WO_IN );
testcase( pTerm->eOperator==WO_ISNULL );
if( pTerm->eOperator & (WO_IN|WO_ISNULL) ) continue;
nTerm++;
}
/* If the ORDER BY clause contains only columns in the current
** virtual table then allocate space for the aOrderBy part of
** the sqlite3_index_info structure.
*/
nOrderBy = 0;
if( pOrderBy ){
for(i=0; i<pOrderBy->nExpr; i++){
Expr *pExpr = pOrderBy->a[i].pExpr;
if( pExpr->op!=TK_COLUMN || pExpr->iTable!=pSrc->iCursor ) break;
}
if( i==pOrderBy->nExpr ){
nOrderBy = pOrderBy->nExpr;
}
}
/* Allocate the sqlite3_index_info structure
*/
pIdxInfo = sqlite3DbMallocZero(pParse->db, sizeof(*pIdxInfo)
+ (sizeof(*pIdxCons) + sizeof(*pUsage))*nTerm
+ sizeof(*pIdxOrderBy)*nOrderBy );
if( pIdxInfo==0 ){
sqlite3ErrorMsg(pParse, "out of memory");
return 0.0;
}
sqlite-amalgamation.c view on Meta::CPAN
pIdxInfo->estimatedCost = SQLITE_BIG_DBL / 2.0;
nOrderBy = pIdxInfo->nOrderBy;
if( pIdxInfo->nOrderBy && !orderByUsable ){
*(int*)&pIdxInfo->nOrderBy = 0;
}
(void)sqlite3SafetyOff(pParse->db);
WHERETRACE(("xBestIndex for %s\n", pTab->zName));
TRACE_IDX_INPUTS(pIdxInfo);
rc = pVtab->pModule->xBestIndex(pVtab, pIdxInfo);
TRACE_IDX_OUTPUTS(pIdxInfo);
(void)sqlite3SafetyOn(pParse->db);
if( rc!=SQLITE_OK ){
if( rc==SQLITE_NOMEM ){
pParse->db->mallocFailed = 1;
}else if( !pVtab->zErrMsg ){
sqlite3ErrorMsg(pParse, "%s", sqlite3ErrStr(rc));
}else{
sqlite3ErrorMsg(pParse, "%s", pVtab->zErrMsg);
}
}
sqlite3DbFree(pParse->db, pVtab->zErrMsg);
pVtab->zErrMsg = 0;
for(i=0; i<pIdxInfo->nConstraint; i++){
if( !pIdxInfo->aConstraint[i].usable && pUsage[i].argvIndex>0 ){
sqlite3ErrorMsg(pParse,
"table %s: xBestIndex returned an invalid plan", pTab->zName);
return 0.0;
}
}
*(int*)&pIdxInfo->nOrderBy = nOrderBy;
return pIdxInfo->estimatedCost;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
/*
** Find the best index for accessing a particular table. Return a pointer
** to the index, flags that describe how the index should be used, the
** number of equality constraints, and the "cost" for this index.
**
** The lowest cost index wins. The cost is an estimate of the amount of
** CPU and disk I/O need to process the request using the selected index.
** Factors that influence cost include:
**
** * The estimated number of rows that will be retrieved. (The
** fewer the better.)
**
** * Whether or not sorting must occur.
**
** * Whether or not there must be separate lookups in the
** index and in the main table.
**
*/
static double bestIndex(
Parse *pParse, /* The parsing context */
WhereClause *pWC, /* The WHERE clause */
struct SrcList_item *pSrc, /* The FROM clause term to search */
Bitmask notReady, /* Mask of cursors that are not available */
ExprList *pOrderBy, /* The order by clause */
Index **ppIndex, /* Make *ppIndex point to the best index */
int *pFlags, /* Put flags describing this choice in *pFlags */
int *pnEq /* Put the number of == or IN constraints here */
){
WhereTerm *pTerm;
Index *bestIdx = 0; /* Index that gives the lowest cost */
double lowestCost; /* The cost of using bestIdx */
int bestFlags = 0; /* Flags associated with bestIdx */
int bestNEq = 0; /* Best value for nEq */
int iCur = pSrc->iCursor; /* The cursor of the table to be accessed */
Index *pProbe; /* An index we are evaluating */
int rev; /* True to scan in reverse order */
int flags; /* Flags associated with pProbe */
int nEq; /* Number of == or IN constraints */
int eqTermMask; /* Mask of valid equality operators */
double cost; /* Cost of using pProbe */
WHERETRACE(("bestIndex: tbl=%s notReady=%llx\n", pSrc->pTab->zName, notReady));
lowestCost = SQLITE_BIG_DBL;
pProbe = pSrc->pTab->pIndex;
/* If the table has no indices and there are no terms in the where
** clause that refer to the ROWID, then we will never be able to do
** anything other than a full table scan on this table. We might as
** well put it first in the join order. That way, perhaps it can be
** referenced by other tables in the join.
*/
if( pProbe==0 &&
findTerm(pWC, iCur, -1, 0, WO_EQ|WO_IN|WO_LT|WO_LE|WO_GT|WO_GE,0)==0 &&
(pOrderBy==0 || !sortableByRowid(iCur, pOrderBy, pWC->pMaskSet, &rev)) ){
*pFlags = 0;
*ppIndex = 0;
*pnEq = 0;
return 0.0;
}
/* Check for a rowid=EXPR or rowid IN (...) constraints
*/
pTerm = findTerm(pWC, iCur, -1, notReady, WO_EQ|WO_IN, 0);
if( pTerm ){
Expr *pExpr;
*ppIndex = 0;
bestFlags = WHERE_ROWID_EQ;
if( pTerm->eOperator & WO_EQ ){
/* Rowid== is always the best pick. Look no further. Because only
** a single row is generated, output is always in sorted order */
*pFlags = WHERE_ROWID_EQ | WHERE_UNIQUE;
*pnEq = 1;
WHERETRACE(("... best is rowid\n"));
return 0.0;
}else if( (pExpr = pTerm->pExpr)->pList!=0 ){
/* Rowid IN (LIST): cost is NlogN where N is the number of list
** elements. */
lowestCost = pExpr->pList->nExpr;
lowestCost *= estLog(lowestCost);
}else{
/* Rowid IN (SELECT): cost is NlogN where N is the number of rows
** in the result of the inner select. We have no way to estimate
** that value so make a wild guess. */
lowestCost = 200;
}
WHERETRACE(("... rowid IN cost: %.9g\n", lowestCost));
}
/* Estimate the cost of a table scan. If we do not know how many
** entries are in the table, use 1 million as a guess.
*/
cost = pProbe ? pProbe->aiRowEst[0] : 1000000;
WHERETRACE(("... table scan base cost: %.9g\n", cost));
flags = WHERE_ROWID_RANGE;
sqlite-amalgamation.c view on Meta::CPAN
sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0);
VdbeComment((v, "%.*s", pX->span.n, pX->span.z));
if( pLevel->nIn==0 ){
pLevel->nxt = sqlite3VdbeMakeLabel(v);
}
pLevel->nIn++;
pLevel->aInLoop = sqlite3DbReallocOrFree(pParse->db, pLevel->aInLoop,
sizeof(pLevel->aInLoop[0])*pLevel->nIn);
pIn = pLevel->aInLoop;
if( pIn ){
pIn += pLevel->nIn - 1;
pIn->iCur = iTab;
if( eType==IN_INDEX_ROWID ){
pIn->topAddr = sqlite3VdbeAddOp2(v, OP_Rowid, iTab, iReg);
}else{
pIn->topAddr = sqlite3VdbeAddOp3(v, OP_Column, iTab, 0, iReg);
}
sqlite3VdbeAddOp1(v, OP_IsNull, iReg);
}else{
pLevel->nIn = 0;
}
#endif
}
disableTerm(pLevel, pTerm);
return iReg;
}
/*
** Generate code that will evaluate all == and IN constraints for an
** index. The values for all constraints are left on the stack.
**
** For example, consider table t1(a,b,c,d,e,f) with index i1(a,b,c).
** Suppose the WHERE clause is this: a==5 AND b IN (1,2,3) AND c>5 AND c<10
** The index has as many as three equality constraints, but in this
** example, the third "c" value is an inequality. So only two
** constraints are coded. This routine will generate code to evaluate
** a==5 and b IN (1,2,3). The current values for a and b will be left
** on the stack - a is the deepest and b the shallowest.
**
** In the example above nEq==2. But this subroutine works for any value
** of nEq including 0. If nEq==0, this routine is nearly a no-op.
** The only thing it does is allocate the pLevel->iMem memory cell.
**
** This routine always allocates at least one memory cell and puts
** the address of that memory cell in pLevel->iMem. The code that
** calls this routine will use pLevel->iMem to store the termination
** key value of the loop. If one or more IN operators appear, then
** this routine allocates an additional nEq memory cells for internal
** use.
*/
static int codeAllEqualityTerms(
Parse *pParse, /* Parsing context */
WhereLevel *pLevel, /* Which nested loop of the FROM we are coding */
WhereClause *pWC, /* The WHERE clause */
Bitmask notReady, /* Which parts of FROM have not yet been coded */
int nExtraReg /* Number of extra registers to allocate */
){
int nEq = pLevel->nEq; /* The number of == or IN constraints to code */
Vdbe *v = pParse->pVdbe; /* The virtual machine under construction */
Index *pIdx = pLevel->pIdx; /* The index being used for this loop */
int iCur = pLevel->iTabCur; /* The cursor of the table */
WhereTerm *pTerm; /* A single constraint term */
int j; /* Loop counter */
int regBase; /* Base register */
/* Figure out how many memory cells we will need then allocate them.
** We always need at least one used to store the loop terminator
** value. If there are IN operators we'll need one for each == or
** IN constraint.
*/
pLevel->iMem = pParse->nMem + 1;
regBase = pParse->nMem + 2;
pParse->nMem += pLevel->nEq + 2 + nExtraReg;
/* Evaluate the equality constraints
*/
assert( pIdx->nColumn>=nEq );
for(j=0; j<nEq; j++){
int r1;
int k = pIdx->aiColumn[j];
pTerm = findTerm(pWC, iCur, k, notReady, pLevel->flags, pIdx);
if( NEVER(pTerm==0) ) break;
assert( (pTerm->flags & TERM_CODED)==0 );
r1 = codeEqualityTerm(pParse, pTerm, pLevel, regBase+j);
if( r1!=regBase+j ){
sqlite3VdbeAddOp2(v, OP_SCopy, r1, regBase+j);
}
testcase( pTerm->eOperator & WO_ISNULL );
testcase( pTerm->eOperator & WO_IN );
if( (pTerm->eOperator & (WO_ISNULL|WO_IN))==0 ){
sqlite3VdbeAddOp2(v, OP_IsNull, regBase+j, pLevel->brk);
}
}
return regBase;
}
#if defined(SQLITE_TEST)
/*
** The following variable holds a text description of query plan generated
** by the most recent call to sqlite3WhereBegin(). Each call to WhereBegin
** overwrites the previous. This information is used for testing and
** analysis only.
*/
SQLITE_API char sqlite3_query_plan[BMS*2*40]; /* Text of the join */
static int nQPlan = 0; /* Next free slow in _query_plan[] */
#endif /* SQLITE_TEST */
/*
** Free a WhereInfo structure
*/
static void whereInfoFree(WhereInfo *pWInfo){
if( pWInfo ){
int i;
sqlite3 *db = pWInfo->pParse->db;
for(i=0; i<pWInfo->nLevel; i++){
sqlite3_index_info *pInfo = pWInfo->a[i].pIdxInfo;
if( pInfo ){
assert( pInfo->needToFreeIdxStr==0 );
sqlite3DbFree(db, pInfo);
}
}
sqlite3DbFree(db, pWInfo);
}
}
/*
** Generate the beginning of the loop used for WHERE clause processing.
** The return value is a pointer to an opaque structure that contains
** information needed to terminate the loop. Later, the calling routine
** should invoke sqlite3WhereEnd() with the return value of this function
** in order to complete the WHERE clause processing.
**
** If an error occurs, this routine returns NULL.
**
** The basic idea is to do a nested loop, one loop for each table in
** the FROM clause of a select. (INSERT and UPDATE statements are the
** same as a SELECT with only a single table in the FROM clause.) For
** example, if the SQL is this:
**
** SELECT * FROM t1, t2, t3 WHERE ...;
**
** Then the code generated is conceptually like the following:
**
** foreach row1 in t1 do \ Code generated
** foreach row2 in t2 do |-- by sqlite3WhereBegin()
** foreach row3 in t3 do /
** ...
** end \ Code generated
** end |-- by sqlite3WhereEnd()
** end /
**
** Note that the loops might not be nested in the order in which they
** appear in the FROM clause if a different order is better able to make
** use of indices. Note also that when the IN operator appears in
** the WHERE clause, it might result in additional nested loops for
** scanning through all values on the right-hand side of the IN.
**
** There are Btree cursors associated with each table. t1 uses cursor
** number pTabList->a[0].iCursor. t2 uses the cursor pTabList->a[1].iCursor.
** And so forth. This routine generates code to open those VDBE cursors
** and sqlite3WhereEnd() generates the code to close them.
**
** The code that sqlite3WhereBegin() generates leaves the cursors named
** in pTabList pointing at their appropriate entries. The [...] code
** can use OP_Column and OP_Rowid opcodes on these cursors to extract
** data from the various tables of the loop.
**
** If the WHERE clause is empty, the foreach loops must each scan their
** entire tables. Thus a three-way join is an O(N^3) operation. But if
** the tables have indices and there are terms in the WHERE clause that
** refer to those indices, a complete table scan can be avoided and the
** code will run much faster. Most of the work of this routine is checking
** to see if there are indices that can be used to speed up the loop.
**
** Terms of the WHERE clause are also used to limit which rows actually
** make it to the "..." in the middle of the loop. After each "foreach",
** terms of the WHERE clause that use only terms in that loop and outer
** loops are evaluated and if false a jump is made around all subsequent
** inner loops (or around the "..." if the test occurs within the inner-
** most loop)
**
** OUTER JOINS
**
** An outer join of tables t1 and t2 is conceptally coded as follows:
**
** foreach row1 in t1 do
** flag = 0
** foreach row2 in t2 do
** start:
** ...
** flag = 1
** end
** if flag==0 then
** move the row2 cursor to a null row
** goto start
** fi
** end
**
** ORDER BY CLAUSE PROCESSING
**
** *ppOrderBy is a pointer to the ORDER BY clause of a SELECT statement,
** if there is one. If there is no ORDER BY clause or if this routine
** is called from an UPDATE or DELETE statement, then ppOrderBy is NULL.
**
** If an index can be used so that the natural output order of the table
** scan is correct for the ORDER BY clause, then that index is used and
** *ppOrderBy is set to NULL. This is an optimization that prevents an
** unnecessary sort of the result set if an index appropriate for the
** ORDER BY clause already exists.
**
** If the where clause loops cannot be arranged to provide the correct
** output order, then the *ppOrderBy is unchanged.
*/
SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* A list of all tables to be scanned */
Expr *pWhere, /* The WHERE clause */
ExprList **ppOrderBy, /* An ORDER BY clause, or NULL */
u8 wflags /* One of the WHERE_* flags defined in sqliteInt.h */
){
int i; /* Loop counter */
WhereInfo *pWInfo; /* Will become the return value of this function */
Vdbe *v = pParse->pVdbe; /* The virtual database engine */
int brk, cont = 0; /* Addresses used during code generation */
Bitmask notReady; /* Cursors that are not yet positioned */
WhereTerm *pTerm; /* A single term in the WHERE clause */
ExprMaskSet maskSet; /* The expression mask set */
WhereClause wc; /* The WHERE clause is divided into these terms */
struct SrcList_item *pTabItem; /* A single entry from pTabList */
WhereLevel *pLevel; /* A single level in the pWInfo list */
int iFrom; /* First unused FROM clause element */
int andFlags; /* AND-ed combination of all wc.a[].flags */
sqlite3 *db; /* Database connection */
ExprList *pOrderBy = 0;
/* The number of tables in the FROM clause is limited by the number of
** bits in a Bitmask
*/
if( pTabList->nSrc>BMS ){
sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
return 0;
}
if( ppOrderBy ){
pOrderBy = *ppOrderBy;
}
/* Split the WHERE clause into separate subexpressions where each
** subexpression is separated by an AND operator.
*/
initMaskSet(&maskSet);
whereClauseInit(&wc, pParse, &maskSet);
sqlite3ExprCodeConstants(pParse, pWhere);
whereSplit(&wc, pWhere, TK_AND);
/* Allocate and initialize the WhereInfo structure that will become the
** return value.
*/
db = pParse->db;
pWInfo = sqlite3DbMallocZero(db,
sizeof(WhereInfo) + pTabList->nSrc*sizeof(WhereLevel));
if( db->mallocFailed ){
goto whereBeginNoMem;
}
pWInfo->nLevel = pTabList->nSrc;
pWInfo->pParse = pParse;
pWInfo->pTabList = pTabList;
pWInfo->iBreak = sqlite3VdbeMakeLabel(v);
/* Special case: a WHERE clause that is constant. Evaluate the
** expression and either jump over all of the code or fall thru.
*/
if( pWhere && (pTabList->nSrc==0 || sqlite3ExprIsConstantNotJoin(pWhere)) ){
sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, SQLITE_JUMPIFNULL);
pWhere = 0;
}
/* Assign a bit from the bitmask to every term in the FROM clause.
**
** When assigning bitmask values to FROM clause cursors, it must be
** the case that if X is the bitmask for the N-th FROM clause term then
** the bitmask for all FROM clause terms to the left of the N-th term
** is (X-1). An expression from the ON clause of a LEFT JOIN can use
** its Expr.iRightJoinTable value to find the bitmask of the right table
** of the join. Subtracting one from the right table bitmask gives a
** bitmask for all tables to the left of the join. Knowing the bitmask
** for all tables to the left of a left join is important. Ticket #3015.
*/
for(i=0; i<pTabList->nSrc; i++){
createMask(&maskSet, pTabList->a[i].iCursor);
}
#ifndef NDEBUG
{
Bitmask toTheLeft = 0;
for(i=0; i<pTabList->nSrc; i++){
Bitmask m = getMask(&maskSet, pTabList->a[i].iCursor);
assert( (m-1)==toTheLeft );
toTheLeft |= m;
}
}
#endif
/* Analyze all of the subexpressions. Note that exprAnalyze() might
** add new virtual terms onto the end of the WHERE clause. We do not
** want to analyze these virtual terms, so start analyzing at the end
** and work forward so that the added virtual terms are never processed.
*/
exprAnalyzeAll(pTabList, &wc);
if( db->mallocFailed ){
goto whereBeginNoMem;
}
/* Chose the best index to use for each table in the FROM clause.
**
** This loop fills in the following fields:
**
** pWInfo->a[].pIdx The index to use for this level of the loop.
** pWInfo->a[].flags WHERE_xxx flags associated with pIdx
** pWInfo->a[].nEq The number of == and IN constraints
** pWInfo->a[].iFrom When term of the FROM clause is being coded
** pWInfo->a[].iTabCur The VDBE cursor for the database table
** pWInfo->a[].iIdxCur The VDBE cursor for the index
**
** This loop also figures out the nesting order of tables in the FROM
** clause.
*/
notReady = ~(Bitmask)0;
pTabItem = pTabList->a;
pLevel = pWInfo->a;
andFlags = ~0;
WHERETRACE(("*** Optimizer Start ***\n"));
for(i=iFrom=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
Index *pIdx; /* Index for FROM table at pTabItem */
int flags; /* Flags asssociated with pIdx */
int nEq; /* Number of == or IN constraints */
double cost; /* The cost for pIdx */
int j; /* For looping over FROM tables */
Index *pBest = 0; /* The best index seen so far */
int bestFlags = 0; /* Flags associated with pBest */
int bestNEq = 0; /* nEq associated with pBest */
double lowestCost; /* Cost of the pBest */
int bestJ = 0; /* The value of j */
Bitmask m; /* Bitmask value for j or bestJ */
int once = 0; /* True when first table is seen */
sqlite3_index_info *pIndex; /* Current virtual index */
lowestCost = SQLITE_BIG_DBL;
for(j=iFrom, pTabItem=&pTabList->a[j]; j<pTabList->nSrc; j++, pTabItem++){
int doNotReorder; /* True if this table should not be reordered */
doNotReorder = (pTabItem->jointype & (JT_LEFT|JT_CROSS))!=0;
if( once && doNotReorder ) break;
m = getMask(&maskSet, pTabItem->iCursor);
if( (m & notReady)==0 ){
if( j==iFrom ) iFrom++;
continue;
}
assert( pTabItem->pTab );
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTabItem->pTab) ){
sqlite3_index_info **ppIdxInfo = &pWInfo->a[j].pIdxInfo;
cost = bestVirtualIndex(pParse, &wc, pTabItem, notReady,
ppOrderBy ? *ppOrderBy : 0, i==0,
ppIdxInfo);
flags = WHERE_VIRTUALTABLE;
pIndex = *ppIdxInfo;
if( pIndex && pIndex->orderByConsumed ){
flags = WHERE_VIRTUALTABLE | WHERE_ORDERBY;
}
pIdx = 0;
nEq = 0;
if( (SQLITE_BIG_DBL/2.0)<cost ){
/* The cost is not allowed to be larger than SQLITE_BIG_DBL (the
** inital value of lowestCost in this loop. If it is, then
** the (cost<lowestCost) test below will never be true and
** pLevel->pBestIdx never set.
*/
cost = (SQLITE_BIG_DBL/2.0);
}
}else
#endif
{
sqlite-amalgamation.c view on Meta::CPAN
}else if( pLevel->flags & (WHERE_ROWID_EQ|WHERE_ROWID_RANGE) ){
zMsg = sqlite3MAppendf(db, zMsg, "%s USING PRIMARY KEY", zMsg);
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
else if( pLevel->pBestIdx ){
sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
zMsg = sqlite3MAppendf(db, zMsg, "%s VIRTUAL TABLE INDEX %d:%s", zMsg,
pBestIdx->idxNum, pBestIdx->idxStr);
}
#endif
if( pLevel->flags & WHERE_ORDERBY ){
zMsg = sqlite3MAppendf(db, zMsg, "%s ORDER BY", zMsg);
}
sqlite3VdbeAddOp4(v, OP_Explain, i, pLevel->iFrom, 0, zMsg, P4_DYNAMIC);
}
#endif /* SQLITE_OMIT_EXPLAIN */
pTabItem = &pTabList->a[pLevel->iFrom];
pTab = pTabItem->pTab;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
if( pTab->isEphem || pTab->pSelect ) continue;
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pLevel->pBestIdx ){
int iCur = pTabItem->iCursor;
sqlite3VdbeAddOp4(v, OP_VOpen, iCur, 0, 0,
(const char*)pTab->pVtab, P4_VTAB);
}else
#endif
if( (pLevel->flags & WHERE_IDX_ONLY)==0 ){
int op = pWInfo->okOnePass ? OP_OpenWrite : OP_OpenRead;
sqlite3OpenTable(pParse, pTabItem->iCursor, iDb, pTab, op);
if( !pWInfo->okOnePass && pTab->nCol<(sizeof(Bitmask)*8) ){
Bitmask b = pTabItem->colUsed;
int n = 0;
for(; b; b=b>>1, n++){}
sqlite3VdbeChangeP2(v, sqlite3VdbeCurrentAddr(v)-2, n);
assert( n<=pTab->nCol );
}
}else{
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
}
pLevel->iTabCur = pTabItem->iCursor;
if( (pIx = pLevel->pIdx)!=0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIx);
assert( pIx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pIx->nColumn+1);
sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIx->zName));
}
sqlite3CodeVerifySchema(pParse, iDb);
}
pWInfo->iTop = sqlite3VdbeCurrentAddr(v);
/* Generate the code to do the search. Each iteration of the for
** loop below generates code for a single nested loop of the VM
** program.
*/
notReady = ~(Bitmask)0;
for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
int j;
int iCur = pTabItem->iCursor; /* The VDBE cursor for the table */
Index *pIdx; /* The index we will be using */
int nxt; /* Where to jump to continue with the next IN case */
int iIdxCur; /* The VDBE cursor for the index */
int omitTable; /* True if we use the index only */
int bRev; /* True if we need to scan in reverse order */
pTabItem = &pTabList->a[pLevel->iFrom];
iCur = pTabItem->iCursor;
pIdx = pLevel->pIdx;
iIdxCur = pLevel->iIdxCur;
bRev = (pLevel->flags & WHERE_REVERSE)!=0;
omitTable = (pLevel->flags & WHERE_IDX_ONLY)!=0;
/* Create labels for the "break" and "continue" instructions
** for the current loop. Jump to brk to break out of a loop.
** Jump to cont to go immediately to the next iteration of the
** loop.
**
** When there is an IN operator, we also have a "nxt" label that
** means to continue with the next IN value combination. When
** there are no IN operators in the constraints, the "nxt" label
** is the same as "brk".
*/
brk = pLevel->brk = pLevel->nxt = sqlite3VdbeMakeLabel(v);
cont = pLevel->cont = sqlite3VdbeMakeLabel(v);
/* If this is the right table of a LEFT OUTER JOIN, allocate and
** initialize a memory cell that records if this table matches any
** row of the left table of the join.
*/
if( pLevel->iFrom>0 && (pTabItem[0].jointype & JT_LEFT)!=0 ){
pLevel->iLeftJoin = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, pLevel->iLeftJoin);
VdbeComment((v, "init LEFT JOIN no-match flag"));
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( pLevel->pBestIdx ){
/* Case 0: The table is a virtual-table. Use the VFilter and VNext
** to access the data.
*/
int j;
int iReg; /* P3 Value for OP_VFilter */
sqlite3_index_info *pBestIdx = pLevel->pBestIdx;
int nConstraint = pBestIdx->nConstraint;
struct sqlite3_index_constraint_usage *aUsage =
pBestIdx->aConstraintUsage;
const struct sqlite3_index_constraint *aConstraint =
pBestIdx->aConstraint;
iReg = sqlite3GetTempRange(pParse, nConstraint+2);
pParse->disableColCache++;
for(j=1; j<=nConstraint; j++){
int k;
for(k=0; k<nConstraint; k++){
if( aUsage[k].argvIndex==j ){
int iTerm = aConstraint[k].iTermOffset;
assert( pParse->disableColCache );
sqlite3ExprCode(pParse, wc.a[iTerm].pExpr->pRight, iReg+j+1);
break;
}
}
if( k==nConstraint ) break;
sqlite-amalgamation.c view on Meta::CPAN
int r1; /* Temp register */
WhereTerm *pRangeStart = 0; /* Inequality constraint at range start */
WhereTerm *pRangeEnd = 0; /* Inequality constraint at range end */
int startEq; /* True if range start uses ==, >= or <= */
int endEq; /* True if range end uses ==, >= or <= */
int start_constraints; /* Start of range is constrained */
int k = pIdx->aiColumn[nEq]; /* Column for inequality constraints */
int nConstraint; /* Number of constraint terms */
int op;
/* Generate code to evaluate all constraint terms using == or IN
** and store the values of those terms in an array of registers
** starting at regBase.
*/
regBase = codeAllEqualityTerms(pParse, pLevel, &wc, notReady, 2);
nxt = pLevel->nxt;
/* If this loop satisfies a sort order (pOrderBy) request that
** was passed to this function to implement a "SELECT min(x) ..."
** query, then the caller will only allow the loop to run for
** a single iteration. This means that the first row returned
** should not have a NULL value stored in 'x'. If column 'x' is
** the first one after the nEq equality constraints in the index,
** this requires some special handling.
*/
if( (wflags&WHERE_ORDERBY_MIN)!=0
&& (pLevel->flags&WHERE_ORDERBY)
&& (pIdx->nColumn>nEq)
){
assert( pOrderBy->nExpr==1 );
assert( pOrderBy->a[0].pExpr->iColumn==pIdx->aiColumn[nEq] );
isMinQuery = 1;
}
/* Find any inequality constraint terms for the start and end
** of the range.
*/
if( pLevel->flags & WHERE_TOP_LIMIT ){
pRangeEnd = findTerm(&wc, iCur, k, notReady, (WO_LT|WO_LE), pIdx);
}
if( pLevel->flags & WHERE_BTM_LIMIT ){
pRangeStart = findTerm(&wc, iCur, k, notReady, (WO_GT|WO_GE), pIdx);
}
/* If we are doing a reverse order scan on an ascending index, or
** a forward order scan on a descending index, interchange the
** start and end terms (pRangeStart and pRangeEnd).
*/
if( bRev==(pIdx->aSortOrder[nEq]==SQLITE_SO_ASC) ){
SWAP(WhereTerm *, pRangeEnd, pRangeStart);
}
testcase( pRangeStart && pRangeStart->eOperator & WO_LE );
testcase( pRangeStart && pRangeStart->eOperator & WO_GE );
testcase( pRangeEnd && pRangeEnd->eOperator & WO_LE );
testcase( pRangeEnd && pRangeEnd->eOperator & WO_GE );
startEq = !pRangeStart || pRangeStart->eOperator & (WO_LE|WO_GE);
endEq = !pRangeEnd || pRangeEnd->eOperator & (WO_LE|WO_GE);
start_constraints = pRangeStart || nEq>0;
/* Seek the index cursor to the start of the range. */
nConstraint = nEq;
if( pRangeStart ){
int dcc = pParse->disableColCache;
if( pRangeEnd ){
pParse->disableColCache++;
}
sqlite3ExprCode(pParse, pRangeStart->pExpr->pRight, regBase+nEq);
pParse->disableColCache = dcc;
sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
nConstraint++;
}else if( isMinQuery ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
nConstraint++;
startEq = 0;
start_constraints = 1;
}
codeApplyAffinity(pParse, regBase, nConstraint, pIdx);
op = aStartOp[(start_constraints<<2) + (startEq<<1) + bRev];
assert( op!=0 );
testcase( op==OP_Rewind );
testcase( op==OP_Last );
testcase( op==OP_MoveGt );
testcase( op==OP_MoveGe );
testcase( op==OP_MoveLe );
testcase( op==OP_MoveLt );
sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase,
SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
/* Load the value for the inequality constraint at the end of the
** range (if any).
*/
nConstraint = nEq;
if( pRangeEnd ){
sqlite3ExprCode(pParse, pRangeEnd->pExpr->pRight, regBase+nEq);
sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
codeApplyAffinity(pParse, regBase, nEq+1, pIdx);
nConstraint++;
}
/* Top of the loop body */
pLevel->p2 = sqlite3VdbeCurrentAddr(v);
/* Check if the index cursor is past the end of the range. */
op = aEndOp[(pRangeEnd || nEq) * (1 + bRev)];
testcase( op==OP_Noop );
testcase( op==OP_IdxGE );
testcase( op==OP_IdxLT );
sqlite3VdbeAddOp4(v, op, iIdxCur, nxt, regBase,
SQLITE_INT_TO_PTR(nConstraint), P4_INT32);
sqlite3VdbeChangeP5(v, endEq!=bRev);
/* If there are inequality constraints, check that the value
** of the table column that the inequality contrains is not NULL.
** If it is, jump to the next iteration of the loop.
*/
r1 = sqlite3GetTempReg(pParse);
testcase( pLevel->flags & WHERE_BTM_LIMIT );
testcase( pLevel->flags & WHERE_TOP_LIMIT );
if( pLevel->flags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT) ){
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
sqlite3VdbeAddOp2(v, OP_IsNull, r1, cont);
}
/* Seek the table cursor, if required */
if( !omitTable ){
sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, r1);
sqlite3VdbeAddOp3(v, OP_MoveGe, iCur, 0, r1); /* Deferred seek */
}
sqlite3ReleaseTempReg(pParse, r1);
/* Record the instruction used to terminate the loop. Disable
** WHERE clause terms made redundant by the index range scan.
*/
pLevel->op = bRev ? OP_Prev : OP_Next;
pLevel->p1 = iIdxCur;
disableTerm(pLevel, pRangeStart);
disableTerm(pLevel, pRangeEnd);
}else{
/* Case 4: There is no usable index. We must do a complete
** scan of the entire table.
*/
assert( omitTable==0 );
assert( bRev==0 );
pLevel->op = OP_Next;
pLevel->p1 = iCur;
pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, OP_Rewind, iCur, brk);
}
notReady &= ~getMask(&maskSet, iCur);
/* Insert code to test every subexpression that can be completely
** computed using the current set of tables.
*/
for(pTerm=wc.a, j=wc.nTerm; j>0; j--, pTerm++){
Expr *pE;
testcase( pTerm->flags & TERM_VIRTUAL );
testcase( pTerm->flags & TERM_CODED );
if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( (pTerm->prereqAll & notReady)!=0 ) continue;
pE = pTerm->pExpr;
assert( pE!=0 );
if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
continue;
}
sqlite3ExprIfFalse(pParse, pE, cont, SQLITE_JUMPIFNULL);
pTerm->flags |= TERM_CODED;
}
/* For a LEFT OUTER JOIN, generate code that will record the fact that
** at least one row of the right table has matched the left table.
*/
if( pLevel->iLeftJoin ){
pLevel->top = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_Integer, 1, pLevel->iLeftJoin);
VdbeComment((v, "record LEFT JOIN hit"));
sqlite3ExprClearColumnCache(pParse, pLevel->iTabCur);
sqlite3ExprClearColumnCache(pParse, pLevel->iIdxCur);
for(pTerm=wc.a, j=0; j<wc.nTerm; j++, pTerm++){
testcase( pTerm->flags & TERM_VIRTUAL );
testcase( pTerm->flags & TERM_CODED );
if( pTerm->flags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( (pTerm->prereqAll & notReady)!=0 ) continue;
assert( pTerm->pExpr );
sqlite3ExprIfFalse(pParse, pTerm->pExpr, cont, SQLITE_JUMPIFNULL);
pTerm->flags |= TERM_CODED;
sqlite-amalgamation.c view on Meta::CPAN
whereClauseClear(&wc);
return pWInfo;
/* Jump here if malloc fails */
whereBeginNoMem:
whereClauseClear(&wc);
whereInfoFree(pWInfo);
return 0;
}
/*
** Generate the end of the WHERE loop. See comments on
** sqlite3WhereBegin() for additional information.
*/
SQLITE_PRIVATE void sqlite3WhereEnd(WhereInfo *pWInfo){
Parse *pParse = pWInfo->pParse;
Vdbe *v = pParse->pVdbe;
int i;
WhereLevel *pLevel;
SrcList *pTabList = pWInfo->pTabList;
sqlite3 *db = pParse->db;
/* Generate loop termination code.
*/
sqlite3ExprClearColumnCache(pParse, -1);
for(i=pTabList->nSrc-1; i>=0; i--){
pLevel = &pWInfo->a[i];
sqlite3VdbeResolveLabel(v, pLevel->cont);
if( pLevel->op!=OP_Noop ){
sqlite3VdbeAddOp2(v, pLevel->op, pLevel->p1, pLevel->p2);
}
if( pLevel->nIn ){
struct InLoop *pIn;
int j;
sqlite3VdbeResolveLabel(v, pLevel->nxt);
for(j=pLevel->nIn, pIn=&pLevel->aInLoop[j-1]; j>0; j--, pIn--){
sqlite3VdbeJumpHere(v, pIn->topAddr+1);
sqlite3VdbeAddOp2(v, OP_Next, pIn->iCur, pIn->topAddr);
sqlite3VdbeJumpHere(v, pIn->topAddr-1);
}
sqlite3DbFree(db, pLevel->aInLoop);
}
sqlite3VdbeResolveLabel(v, pLevel->brk);
if( pLevel->iLeftJoin ){
int addr;
addr = sqlite3VdbeAddOp1(v, OP_IfPos, pLevel->iLeftJoin);
sqlite3VdbeAddOp1(v, OP_NullRow, pTabList->a[i].iCursor);
if( pLevel->iIdxCur>=0 ){
sqlite3VdbeAddOp1(v, OP_NullRow, pLevel->iIdxCur);
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, pLevel->top);
sqlite3VdbeJumpHere(v, addr);
}
}
/* The "break" point is here, just past the end of the outer loop.
** Set it.
*/
sqlite3VdbeResolveLabel(v, pWInfo->iBreak);
/* Close all of the cursors that were opened by sqlite3WhereBegin.
*/
for(i=0, pLevel=pWInfo->a; i<pTabList->nSrc; i++, pLevel++){
struct SrcList_item *pTabItem = &pTabList->a[pLevel->iFrom];
Table *pTab = pTabItem->pTab;
assert( pTab!=0 );
if( pTab->isEphem || pTab->pSelect ) continue;
if( !pWInfo->okOnePass && (pLevel->flags & WHERE_IDX_ONLY)==0 ){
sqlite3VdbeAddOp1(v, OP_Close, pTabItem->iCursor);
}
if( pLevel->pIdx!=0 ){
sqlite3VdbeAddOp1(v, OP_Close, pLevel->iIdxCur);
}
/* If this scan uses an index, make code substitutions to read data
** from the index in preference to the table. Sometimes, this means
** the table need never be read from. This is a performance boost,
** as the vdbe level waits until the table is read before actually
** seeking the table cursor to the record corresponding to the current
** position in the index.
**
** Calls to the code generator in between sqlite3WhereBegin and
** sqlite3WhereEnd will have created code that references the table
** directly. This loop scans all that code looking for opcodes
** that reference the table and converts them into opcodes that
** reference the index.
*/
if( pLevel->pIdx ){
int k, j, last;
VdbeOp *pOp;
Index *pIdx = pLevel->pIdx;
int useIndexOnly = pLevel->flags & WHERE_IDX_ONLY;
assert( pIdx!=0 );
pOp = sqlite3VdbeGetOp(v, pWInfo->iTop);
last = sqlite3VdbeCurrentAddr(v);
for(k=pWInfo->iTop; k<last; k++, pOp++){
if( pOp->p1!=pLevel->iTabCur ) continue;
if( pOp->opcode==OP_Column ){
for(j=0; j<pIdx->nColumn; j++){
if( pOp->p2==pIdx->aiColumn[j] ){
pOp->p2 = j;
pOp->p1 = pLevel->iIdxCur;
break;
}
}
assert(!useIndexOnly || j<pIdx->nColumn);
}else if( pOp->opcode==OP_Rowid ){
pOp->p1 = pLevel->iIdxCur;
pOp->opcode = OP_IdxRowid;
}else if( pOp->opcode==OP_NullRow && useIndexOnly ){
pOp->opcode = OP_Noop;
}
}
}
}
/* Final cleanup
*/
whereInfoFree(pWInfo);
return;
}
/************** End of where.c ***********************************************/
/************** Begin file parse.c *******************************************/
/* Driver template for the LEMON parser generator.
** The author disclaims copyright to this source code.
*/
/* First off, code is included that follows the "include" declaration
** in the input grammar file. */
/*
** An instance of this structure holds information about the
** LIMIT clause of a SELECT statement.
*/
struct LimitVal {
Expr *pLimit; /* The LIMIT expression. NULL if there is no limit */
Expr *pOffset; /* The OFFSET expression. NULL if there is none */
sqlite-amalgamation.c view on Meta::CPAN
** Access routines. To delete, insert a NULL pointer.
*/
SQLITE_PRIVATE void sqlite3Fts3HashInit(fts3Hash*, int keytype, int copyKey);
SQLITE_PRIVATE void *sqlite3Fts3HashInsert(fts3Hash*, const void *pKey, int nKey, void *pData);
SQLITE_PRIVATE void *sqlite3Fts3HashFind(const fts3Hash*, const void *pKey, int nKey);
SQLITE_PRIVATE void sqlite3Fts3HashClear(fts3Hash*);
/*
** Shorthand for the functions above
*/
#define fts3HashInit sqlite3Fts3HashInit
#define fts3HashInsert sqlite3Fts3HashInsert
#define fts3HashFind sqlite3Fts3HashFind
#define fts3HashClear sqlite3Fts3HashClear
/*
** Macros for looping over all elements of a hash table. The idiom is
** like this:
**
** fts3Hash h;
** fts3HashElem *p;
** ...
** for(p=fts3HashFirst(&h); p; p=fts3HashNext(p)){
** SomeStructure *pData = fts3HashData(p);
** // do something with pData
** }
*/
#define fts3HashFirst(H) ((H)->first)
#define fts3HashNext(E) ((E)->next)
#define fts3HashData(E) ((E)->data)
#define fts3HashKey(E) ((E)->pKey)
#define fts3HashKeysize(E) ((E)->nKey)
/*
** Number of entries in a hash table
*/
#define fts3HashCount(H) ((H)->count)
#endif /* _FTS3_HASH_H_ */
/************** End of fts3_hash.h *******************************************/
/************** Continuing where we left off in fts3.c ***********************/
/************** Include fts3_tokenizer.h in the middle of fts3.c *************/
/************** Begin file fts3_tokenizer.h **********************************/
/*
** 2006 July 10
**
** The author disclaims copyright to this source code.
**
*************************************************************************
** Defines the interface to tokenizers used by fulltext-search. There
** are three basic components:
**
** sqlite3_tokenizer_module is a singleton defining the tokenizer
** interface functions. This is essentially the class structure for
** tokenizers.
**
** sqlite3_tokenizer is used to define a particular tokenizer, perhaps
** including customization information defined at creation time.
**
** sqlite3_tokenizer_cursor is generated by a tokenizer to generate
** tokens from a particular input.
*/
#ifndef _FTS3_TOKENIZER_H_
#define _FTS3_TOKENIZER_H_
/* TODO(shess) Only used for SQLITE_OK and SQLITE_DONE at this time.
** If tokenizers are to be allowed to call sqlite3_*() functions, then
** we will need a way to register the API consistently.
*/
/*
** Structures used by the tokenizer interface. When a new tokenizer
** implementation is registered, the caller provides a pointer to
** an sqlite3_tokenizer_module containing pointers to the callback
** functions that make up an implementation.
**
** When an fts3 table is created, it passes any arguments passed to
** the tokenizer clause of the CREATE VIRTUAL TABLE statement to the
** sqlite3_tokenizer_module.xCreate() function of the requested tokenizer
** implementation. The xCreate() function in turn returns an
** sqlite3_tokenizer structure representing the specific tokenizer to
** be used for the fts3 table (customized by the tokenizer clause arguments).
**
** To tokenize an input buffer, the sqlite3_tokenizer_module.xOpen()
** method is called. It returns an sqlite3_tokenizer_cursor object
** that may be used to tokenize a specific input buffer based on
** the tokenization rules supplied by a specific sqlite3_tokenizer
** object.
*/
typedef struct sqlite3_tokenizer_module sqlite3_tokenizer_module;
typedef struct sqlite3_tokenizer sqlite3_tokenizer;
typedef struct sqlite3_tokenizer_cursor sqlite3_tokenizer_cursor;
struct sqlite3_tokenizer_module {
/*
** Structure version. Should always be set to 0.
*/
int iVersion;
/*
** Create a new tokenizer. The values in the argv[] array are the
** arguments passed to the "tokenizer" clause of the CREATE VIRTUAL
** TABLE statement that created the fts3 table. For example, if
** the following SQL is executed:
**
** CREATE .. USING fts3( ... , tokenizer <tokenizer-name> arg1 arg2)
**
** then argc is set to 2, and the argv[] array contains pointers
** to the strings "arg1" and "arg2".
**
** This method should return either SQLITE_OK (0), or an SQLite error
** code. If SQLITE_OK is returned, then *ppTokenizer should be set
** to point at the newly created tokenizer structure. The generic
** sqlite3_tokenizer.pModule variable should not be initialised by
** this callback. The caller will do so.
*/
int (*xCreate)(
int argc, /* Size of argv array */
const char *const*argv, /* Tokenizer argument strings */
sqlite3_tokenizer **ppTokenizer /* OUT: Created tokenizer */
);
/*
** Destroy an existing tokenizer. The fts3 module calls this method
** exactly once for each successful call to xCreate().
*/
int (*xDestroy)(sqlite3_tokenizer *pTokenizer);
/*
** Create a tokenizer cursor to tokenize an input buffer. The caller
** is responsible for ensuring that the input buffer remains valid
** until the cursor is closed (using the xClose() method).
*/
int (*xOpen)(
sqlite3_tokenizer *pTokenizer, /* Tokenizer object */
const char *pInput, int nBytes, /* Input buffer */
sqlite3_tokenizer_cursor **ppCursor /* OUT: Created tokenizer cursor */
);
/*
** Destroy an existing tokenizer cursor. The fts3 module calls this
** method exactly once for each successful call to xOpen().
*/
int (*xClose)(sqlite3_tokenizer_cursor *pCursor);
/*
** Retrieve the next token from the tokenizer cursor pCursor. This
** method should either return SQLITE_OK and set the values of the
** "OUT" variables identified below, or SQLITE_DONE to indicate that
** the end of the buffer has been reached, or an SQLite error code.
**
** *ppToken should be set to point at a buffer containing the
** normalized version of the token (i.e. after any case-folding and/or
** stemming has been performed). *pnBytes should be set to the length
** of this buffer in bytes. The input text that generated the token is
** identified by the byte offsets returned in *piStartOffset and
** *piEndOffset.
**
** The buffer *ppToken is set to point at is managed by the tokenizer
** implementation. It is only required to be valid until the next call
** to xNext() or xClose().
*/
/* TODO(shess) current implementation requires pInput to be
** nul-terminated. This should either be fixed, or pInput/nBytes
** should be converted to zInput.
*/
int (*xNext)(
sqlite3_tokenizer_cursor *pCursor, /* Tokenizer cursor */
const char **ppToken, int *pnBytes, /* OUT: Normalized text for token */
int *piStartOffset, /* OUT: Byte offset of token in input buffer */
int *piEndOffset, /* OUT: Byte offset of end of token in input buffer */
int *piPosition /* OUT: Number of tokens returned before this one */
);
};
struct sqlite3_tokenizer {
const sqlite3_tokenizer_module *pModule; /* The module for this tokenizer */
/* Tokenizer implementations will typically add additional fields */
};
struct sqlite3_tokenizer_cursor {
sqlite3_tokenizer *pTokenizer; /* Tokenizer for this cursor. */
/* Tokenizer implementations will typically add additional fields */
};
#endif /* _FTS3_TOKENIZER_H_ */
/************** End of fts3_tokenizer.h **************************************/
/************** Continuing where we left off in fts3.c ***********************/
#ifndef SQLITE_CORE
SQLITE_EXTENSION_INIT1
#endif
/* TODO(shess) MAN, this thing needs some refactoring. At minimum, it
** would be nice to order the file better, perhaps something along the
** lines of:
**
** - utility functions
** - table setup functions
** - table update functions
** - table query functions
**
** Put the query functions last because they're likely to reference
** typedefs or functions from the table update section.
*/
#if 0
# define FTSTRACE(A) printf A; fflush(stdout)
#else
# define FTSTRACE(A)
#endif
/*
** Default span for NEAR operators.
*/
#define SQLITE_FTS3_DEFAULT_NEAR_PARAM 10
/* It is not safe to call isspace(), tolower(), or isalnum() on
** hi-bit-set characters. This is the same solution used in the
** tokenizer.
*/
/* TODO(shess) The snippet-generation code should be using the
** tokenizer-generated tokens rather than doing its own local
** tokenization.
*/
/* TODO(shess) Is __isascii() a portable version of (c&0x80)==0? */
static int safe_isspace(char c){
return (c&0x80)==0 ? isspace(c) : 0;
}
static int safe_tolower(char c){
return (c&0x80)==0 ? tolower(c) : c;
}
static int safe_isalnum(char c){
return (c&0x80)==0 ? isalnum(c) : 0;
}
typedef enum DocListType {
DL_DOCIDS, /* docids only */
DL_POSITIONS, /* docids + positions */
DL_POSITIONS_OFFSETS /* docids + positions + offsets */
} DocListType;
sqlite-amalgamation.c view on Meta::CPAN
int nextColumn; /* Next word parsed must be in this column */
int dfltColumn; /* The default column */
} Query;
/*
** An instance of the following structure keeps track of generated
** matching-word offset information and snippets.
*/
typedef struct Snippet {
int nMatch; /* Total number of matches */
int nAlloc; /* Space allocated for aMatch[] */
struct snippetMatch { /* One entry for each matching term */
char snStatus; /* Status flag for use while constructing snippets */
short int iCol; /* The column that contains the match */
short int iTerm; /* The index in Query.pTerms[] of the matching term */
int iToken; /* The index of the matching document token */
short int nByte; /* Number of bytes in the term */
int iStart; /* The offset to the first character of the term */
} *aMatch; /* Points to space obtained from malloc */
char *zOffset; /* Text rendering of aMatch[] */
int nOffset; /* strlen(zOffset) */
char *zSnippet; /* Snippet text */
int nSnippet; /* strlen(zSnippet) */
} Snippet;
typedef enum QueryType {
QUERY_GENERIC, /* table scan */
QUERY_DOCID, /* lookup by docid */
QUERY_FULLTEXT /* QUERY_FULLTEXT + [i] is a full-text search for column i*/
} QueryType;
typedef enum fulltext_statement {
CONTENT_INSERT_STMT,
CONTENT_SELECT_STMT,
CONTENT_UPDATE_STMT,
CONTENT_DELETE_STMT,
CONTENT_EXISTS_STMT,
BLOCK_INSERT_STMT,
BLOCK_SELECT_STMT,
BLOCK_DELETE_STMT,
BLOCK_DELETE_ALL_STMT,
SEGDIR_MAX_INDEX_STMT,
SEGDIR_SET_STMT,
SEGDIR_SELECT_LEVEL_STMT,
SEGDIR_SPAN_STMT,
SEGDIR_DELETE_STMT,
SEGDIR_SELECT_SEGMENT_STMT,
SEGDIR_SELECT_ALL_STMT,
SEGDIR_DELETE_ALL_STMT,
SEGDIR_COUNT_STMT,
MAX_STMT /* Always at end! */
} fulltext_statement;
/* These must exactly match the enum above. */
/* TODO(shess): Is there some risk that a statement will be used in two
** cursors at once, e.g. if a query joins a virtual table to itself?
** If so perhaps we should move some of these to the cursor object.
*/
static const char *const fulltext_zStatement[MAX_STMT] = {
/* CONTENT_INSERT */ NULL, /* generated in contentInsertStatement() */
/* CONTENT_SELECT */ NULL, /* generated in contentSelectStatement() */
/* CONTENT_UPDATE */ NULL, /* generated in contentUpdateStatement() */
/* CONTENT_DELETE */ "delete from %_content where docid = ?",
/* CONTENT_EXISTS */ "select docid from %_content limit 1",
/* BLOCK_INSERT */
"insert into %_segments (blockid, block) values (null, ?)",
/* BLOCK_SELECT */ "select block from %_segments where blockid = ?",
/* BLOCK_DELETE */ "delete from %_segments where blockid between ? and ?",
/* BLOCK_DELETE_ALL */ "delete from %_segments",
/* SEGDIR_MAX_INDEX */ "select max(idx) from %_segdir where level = ?",
/* SEGDIR_SET */ "insert into %_segdir values (?, ?, ?, ?, ?, ?)",
/* SEGDIR_SELECT_LEVEL */
"select start_block, leaves_end_block, root from %_segdir "
" where level = ? order by idx",
/* SEGDIR_SPAN */
"select min(start_block), max(end_block) from %_segdir "
" where level = ? and start_block <> 0",
/* SEGDIR_DELETE */ "delete from %_segdir where level = ?",
/* NOTE(shess): The first three results of the following two
** statements must match.
*/
/* SEGDIR_SELECT_SEGMENT */
"select start_block, leaves_end_block, root from %_segdir "
" where level = ? and idx = ?",
/* SEGDIR_SELECT_ALL */
"select start_block, leaves_end_block, root from %_segdir "
" order by level desc, idx asc",
/* SEGDIR_DELETE_ALL */ "delete from %_segdir",
/* SEGDIR_COUNT */ "select count(*), ifnull(max(level),0) from %_segdir",
};
/*
** A connection to a fulltext index is an instance of the following
** structure. The xCreate and xConnect methods create an instance
** of this structure and xDestroy and xDisconnect free that instance.
** All other methods receive a pointer to the structure as one of their
** arguments.
*/
struct fulltext_vtab {
sqlite3_vtab base; /* Base class used by SQLite core */
sqlite3 *db; /* The database connection */
const char *zDb; /* logical database name */
const char *zName; /* virtual table name */
int nColumn; /* number of columns in virtual table */
char **azColumn; /* column names. malloced */
char **azContentColumn; /* column names in content table; malloced */
sqlite3_tokenizer *pTokenizer; /* tokenizer for inserts and queries */
/* Precompiled statements which we keep as long as the table is
** open.
*/
sqlite3_stmt *pFulltextStatements[MAX_STMT];
/* Precompiled statements used for segment merges. We run a
** separate select across the leaf level of each tree being merged.
*/
sqlite3_stmt *pLeafSelectStmts[MERGE_COUNT];
/* The statement used to prepare pLeafSelectStmts. */
#define LEAF_SELECT \
"select block from %_segments where blockid between ? and ? order by blockid"
/* These buffer pending index updates during transactions.
** nPendingData estimates the memory size of the pending data. It
** doesn't include the hash-bucket overhead, nor any malloc
** overhead. When nPendingData exceeds kPendingThreshold, the
** buffer is flushed even before the transaction closes.
** pendingTerms stores the data, and is only valid when nPendingData
** is >=0 (nPendingData<0 means pendingTerms has not been
** initialized). iPrevDocid is the last docid written, used to make
** certain we're inserting in sorted order.
*/
int nPendingData;
#define kPendingThreshold (1*1024*1024)
sqlite_int64 iPrevDocid;
fts3Hash pendingTerms;
};
/*
** When the core wants to do a query, it create a cursor using a
** call to xOpen. This structure is an instance of a cursor. It
** is destroyed by xClose.
*/
typedef struct fulltext_cursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
QueryType iCursorType; /* Copy of sqlite3_index_info.idxNum */
sqlite3_stmt *pStmt; /* Prepared statement in use by the cursor */
int eof; /* True if at End Of Results */
Query q; /* Parsed query string */
Snippet snippet; /* Cached snippet for the current row */
int iColumn; /* Column being searched */
DataBuffer result; /* Doclist results from fulltextQuery */
DLReader reader; /* Result reader if result not empty */
} fulltext_cursor;
static struct fulltext_vtab *cursor_vtab(fulltext_cursor *c){
return (fulltext_vtab *) c->base.pVtab;
}
static const sqlite3_module fts3Module; /* forward declaration */
/* Return a dynamically generated statement of the form
* insert into %_content (docid, ...) values (?, ...)
*/
static const char *contentInsertStatement(fulltext_vtab *v){
StringBuffer sb;
int i;
initStringBuffer(&sb);
append(&sb, "insert into %_content (docid, ");
appendList(&sb, v->nColumn, v->azContentColumn);
append(&sb, ") values (?");
for(i=0; i<v->nColumn; ++i)
append(&sb, ", ?");
append(&sb, ")");
return stringBufferData(&sb);
}
/* Return a dynamically generated statement of the form
* select <content columns> from %_content where docid = ?
*/
static const char *contentSelectStatement(fulltext_vtab *v){
StringBuffer sb;
initStringBuffer(&sb);
append(&sb, "SELECT ");
appendList(&sb, v->nColumn, v->azContentColumn);
append(&sb, " FROM %_content WHERE docid = ?");
return stringBufferData(&sb);
}
/* Return a dynamically generated statement of the form
* update %_content set [col_0] = ?, [col_1] = ?, ...
* where docid = ?
*/
static const char *contentUpdateStatement(fulltext_vtab *v){
StringBuffer sb;
int i;
initStringBuffer(&sb);
append(&sb, "update %_content set ");
for(i=0; i<v->nColumn; ++i) {
if( i>0 ){
append(&sb, ", ");
}
append(&sb, v->azContentColumn[i]);
append(&sb, " = ?");
}
append(&sb, " where docid = ?");
return stringBufferData(&sb);
}
/* Puts a freshly-prepared statement determined by iStmt in *ppStmt.
** If the indicated statement has never been prepared, it is prepared
** and cached, otherwise the cached version is reset.
*/
static int sql_get_statement(fulltext_vtab *v, fulltext_statement iStmt,
sqlite-amalgamation.c view on Meta::CPAN
}
/* Decide how to handle an SQL query. */
static int fulltextBestIndex(sqlite3_vtab *pVTab, sqlite3_index_info *pInfo){
fulltext_vtab *v = (fulltext_vtab *)pVTab;
int i;
FTSTRACE(("FTS3 BestIndex\n"));
for(i=0; i<pInfo->nConstraint; ++i){
const struct sqlite3_index_constraint *pConstraint;
pConstraint = &pInfo->aConstraint[i];
if( pConstraint->usable ) {
if( (pConstraint->iColumn==-1 || pConstraint->iColumn==v->nColumn+1) &&
pConstraint->op==SQLITE_INDEX_CONSTRAINT_EQ ){
pInfo->idxNum = QUERY_DOCID; /* lookup by docid */
FTSTRACE(("FTS3 QUERY_DOCID\n"));
} else if( pConstraint->iColumn>=0 && pConstraint->iColumn<=v->nColumn &&
pConstraint->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
/* full-text search */
pInfo->idxNum = QUERY_FULLTEXT + pConstraint->iColumn;
FTSTRACE(("FTS3 QUERY_FULLTEXT %d\n", pConstraint->iColumn));
} else continue;
pInfo->aConstraintUsage[i].argvIndex = 1;
pInfo->aConstraintUsage[i].omit = 1;
/* An arbitrary value for now.
* TODO: Perhaps docid matches should be considered cheaper than
* full-text searches. */
pInfo->estimatedCost = 1.0;
return SQLITE_OK;
}
}
pInfo->idxNum = QUERY_GENERIC;
return SQLITE_OK;
}
static int fulltextDisconnect(sqlite3_vtab *pVTab){
FTSTRACE(("FTS3 Disconnect %p\n", pVTab));
fulltext_vtab_destroy((fulltext_vtab *)pVTab);
return SQLITE_OK;
}
static int fulltextDestroy(sqlite3_vtab *pVTab){
fulltext_vtab *v = (fulltext_vtab *)pVTab;
int rc;
FTSTRACE(("FTS3 Destroy %p\n", pVTab));
rc = sql_exec(v->db, v->zDb, v->zName,
"drop table if exists %_content;"
"drop table if exists %_segments;"
"drop table if exists %_segdir;"
);
if( rc!=SQLITE_OK ) return rc;
fulltext_vtab_destroy((fulltext_vtab *)pVTab);
return SQLITE_OK;
}
static int fulltextOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
fulltext_cursor *c;
c = (fulltext_cursor *) sqlite3_malloc(sizeof(fulltext_cursor));
if( c ){
memset(c, 0, sizeof(fulltext_cursor));
/* sqlite will initialize c->base */
*ppCursor = &c->base;
FTSTRACE(("FTS3 Open %p: %p\n", pVTab, c));
return SQLITE_OK;
}else{
return SQLITE_NOMEM;
}
}
/* Free all of the dynamically allocated memory held by *q
*/
static void queryClear(Query *q){
int i;
for(i = 0; i < q->nTerms; ++i){
sqlite3_free(q->pTerms[i].pTerm);
}
sqlite3_free(q->pTerms);
CLEAR(q);
}
/* Free all of the dynamically allocated memory held by the
** Snippet
*/
static void snippetClear(Snippet *p){
sqlite3_free(p->aMatch);
sqlite3_free(p->zOffset);
sqlite3_free(p->zSnippet);
CLEAR(p);
}
/*
** Append a single entry to the p->aMatch[] log.
*/
static void snippetAppendMatch(
Snippet *p, /* Append the entry to this snippet */
int iCol, int iTerm, /* The column and query term */
int iToken, /* Matching token in document */
int iStart, int nByte /* Offset and size of the match */
){
int i;
struct snippetMatch *pMatch;
if( p->nMatch+1>=p->nAlloc ){
p->nAlloc = p->nAlloc*2 + 10;
p->aMatch = sqlite3_realloc(p->aMatch, p->nAlloc*sizeof(p->aMatch[0]) );
if( p->aMatch==0 ){
p->nMatch = 0;
p->nAlloc = 0;
return;
}
}
i = p->nMatch++;
pMatch = &p->aMatch[i];
pMatch->iCol = iCol;
pMatch->iTerm = iTerm;
pMatch->iToken = iToken;
pMatch->iStart = iStart;
pMatch->nByte = nByte;
}
/*
** Sizing information for the circular buffer used in snippetOffsetsOfColumn()
*/
#define FTS3_ROTOR_SZ (32)
#define FTS3_ROTOR_MASK (FTS3_ROTOR_SZ-1)
/*
** Add entries to pSnippet->aMatch[] for every match that occurs against
** document zDoc[0..nDoc-1] which is stored in column iColumn.
*/
static void snippetOffsetsOfColumn(
Query *pQuery,
Snippet *pSnippet,
int iColumn,
const char *zDoc,
int nDoc
){
const sqlite3_tokenizer_module *pTModule; /* The tokenizer module */
sqlite3_tokenizer *pTokenizer; /* The specific tokenizer */
sqlite3_tokenizer_cursor *pTCursor; /* Tokenizer cursor */
fulltext_vtab *pVtab; /* The full text index */
int nColumn; /* Number of columns in the index */
const QueryTerm *aTerm; /* Query string terms */
int nTerm; /* Number of query string terms */
int i, j; /* Loop counters */
int rc; /* Return code */
unsigned int match, prevMatch; /* Phrase search bitmasks */
const char *zToken; /* Next token from the tokenizer */
int nToken; /* Size of zToken */
int iBegin, iEnd, iPos; /* Offsets of beginning and end */
/* The following variables keep a circular buffer of the last
** few tokens */
unsigned int iRotor = 0; /* Index of current token */
int iRotorBegin[FTS3_ROTOR_SZ]; /* Beginning offset of token */
int iRotorLen[FTS3_ROTOR_SZ]; /* Length of token */
pVtab = pQuery->pFts;
nColumn = pVtab->nColumn;
pTokenizer = pVtab->pTokenizer;
pTModule = pTokenizer->pModule;
rc = pTModule->xOpen(pTokenizer, zDoc, nDoc, &pTCursor);
if( rc ) return;
pTCursor->pTokenizer = pTokenizer;
aTerm = pQuery->pTerms;
nTerm = pQuery->nTerms;
if( nTerm>=FTS3_ROTOR_SZ ){
nTerm = FTS3_ROTOR_SZ - 1;
}
prevMatch = 0;
while(1){
rc = pTModule->xNext(pTCursor, &zToken, &nToken, &iBegin, &iEnd, &iPos);
if( rc ) break;
iRotorBegin[iRotor&FTS3_ROTOR_MASK] = iBegin;
iRotorLen[iRotor&FTS3_ROTOR_MASK] = iEnd-iBegin;
match = 0;
for(i=0; i<nTerm; i++){
int iCol;
iCol = aTerm[i].iColumn;
if( iCol>=0 && iCol<nColumn && iCol!=iColumn ) continue;
if( aTerm[i].nTerm>nToken ) continue;
if( !aTerm[i].isPrefix && aTerm[i].nTerm<nToken ) continue;
assert( aTerm[i].nTerm<=nToken );
if( memcmp(aTerm[i].pTerm, zToken, aTerm[i].nTerm) ) continue;
if( aTerm[i].iPhrase>1 && (prevMatch & (1<<i))==0 ) continue;
match |= 1<<i;
if( i==nTerm-1 || aTerm[i+1].iPhrase==1 ){
for(j=aTerm[i].iPhrase-1; j>=0; j--){
int k = (iRotor-j) & FTS3_ROTOR_MASK;
snippetAppendMatch(pSnippet, iColumn, i-j, iPos-j,
iRotorBegin[k], iRotorLen[k]);
}
}
}
prevMatch = match<<1;
iRotor++;
}
pTModule->xClose(pTCursor);
}
sqlite-amalgamation.c view on Meta::CPAN
int iNextTerm = pMatch->iTerm+iDir;
int iPrevTerm = iNextTerm;
int iEndToken;
int iStartToken;
if( iDir<0 ){
int nPhrase = 1;
iStartToken = pMatch->iToken;
while( (pMatch->iTerm+nPhrase)<pQuery->nTerms
&& pQuery->pTerms[pMatch->iTerm+nPhrase].iPhrase>1
){
nPhrase++;
}
iEndToken = iStartToken + nPhrase - 1;
}else{
iEndToken = pMatch->iToken;
iStartToken = pMatch->iToken+1-pQueryTerm->iPhrase;
}
while( pQuery->pTerms[iNextTerm].iPhrase>1 ){
iNextTerm--;
}
while( (iPrevTerm+1)<pQuery->nTerms &&
pQuery->pTerms[iPrevTerm+1].iPhrase>1
){
iPrevTerm++;
}
for(jj=0; isOk==0 && jj<pSnippet->nMatch; jj++){
struct snippetMatch *p = &pSnippet->aMatch[jj];
if( p->iCol==pMatch->iCol && ((
p->iTerm==iNextTerm &&
p->iToken>iEndToken &&
p->iToken<=iEndToken+nNear
) || (
p->iTerm==iPrevTerm &&
p->iToken<iStartToken &&
p->iToken>=iStartToken-nNear
))){
isOk = 1;
}
}
if( !isOk ){
for(jj=1-pQueryTerm->iPhrase; jj<=0; jj++){
pMatch[jj].iTerm = -1;
}
ii = -1;
iDir = 1;
}
}
}
iDir -= 2;
}
}
/*
** Compute all offsets for the current row of the query.
** If the offsets have already been computed, this routine is a no-op.
*/
static void snippetAllOffsets(fulltext_cursor *p){
int nColumn;
int iColumn, i;
int iFirst, iLast;
fulltext_vtab *pFts;
if( p->snippet.nMatch ) return;
if( p->q.nTerms==0 ) return;
pFts = p->q.pFts;
nColumn = pFts->nColumn;
iColumn = (p->iCursorType - QUERY_FULLTEXT);
if( iColumn<0 || iColumn>=nColumn ){
iFirst = 0;
iLast = nColumn-1;
}else{
iFirst = iColumn;
iLast = iColumn;
}
for(i=iFirst; i<=iLast; i++){
const char *zDoc;
int nDoc;
zDoc = (const char*)sqlite3_column_text(p->pStmt, i+1);
nDoc = sqlite3_column_bytes(p->pStmt, i+1);
snippetOffsetsOfColumn(&p->q, &p->snippet, i, zDoc, nDoc);
}
trimSnippetOffsetsForNear(&p->q, &p->snippet);
}
/*
** Convert the information in the aMatch[] array of the snippet
** into the string zOffset[0..nOffset-1].
*/
static void snippetOffsetText(Snippet *p){
int i;
int cnt = 0;
StringBuffer sb;
char zBuf[200];
if( p->zOffset ) return;
initStringBuffer(&sb);
for(i=0; i<p->nMatch; i++){
struct snippetMatch *pMatch = &p->aMatch[i];
if( pMatch->iTerm>=0 ){
/* If snippetMatch.iTerm is less than 0, then the match was
** discarded as part of processing the NEAR operator (see the
** trimSnippetOffsetsForNear() function for details). Ignore
** it in this case
*/
zBuf[0] = ' ';
sqlite3_snprintf(sizeof(zBuf)-1, &zBuf[cnt>0], "%d %d %d %d",
pMatch->iCol, pMatch->iTerm, pMatch->iStart, pMatch->nByte);
append(&sb, zBuf);
cnt++;
}
}
p->zOffset = stringBufferData(&sb);
p->nOffset = stringBufferLength(&sb);
}
/*
** zDoc[0..nDoc-1] is phrase of text. aMatch[0..nMatch-1] are a set
** of matching words some of which might be in zDoc. zDoc is column
** number iCol.
**
** iBreak is suggested spot in zDoc where we could begin or end an
** excerpt. Return a value similar to iBreak but possibly adjusted
** to be a little left or right so that the break point is better.
*/
static int wordBoundary(
int iBreak, /* The suggested break point */
const char *zDoc, /* Document text */
int nDoc, /* Number of bytes in zDoc[] */
struct snippetMatch *aMatch, /* Matching words */
int nMatch, /* Number of entries in aMatch[] */
int iCol /* The column number for zDoc[] */
){
int i;
if( iBreak<=10 ){
return 0;
}
if( iBreak>=nDoc-10 ){
return nDoc;
}
for(i=0; i<nMatch && aMatch[i].iCol<iCol; i++){}
while( i<nMatch && aMatch[i].iStart+aMatch[i].nByte<iBreak ){ i++; }
if( i<nMatch ){
if( aMatch[i].iStart<iBreak+10 ){
return aMatch[i].iStart;
}
if( i>0 && aMatch[i-1].iStart+aMatch[i-1].nByte>=iBreak ){
return aMatch[i-1].iStart;
}
}
for(i=1; i<=10; i++){
if( safe_isspace(zDoc[iBreak-i]) ){
return iBreak - i + 1;
}
if( safe_isspace(zDoc[iBreak+i]) ){
return iBreak + i + 1;
}
}
return iBreak;
}
/*
** Allowed values for Snippet.aMatch[].snStatus
*/
#define SNIPPET_IGNORE 0 /* It is ok to omit this match from the snippet */
#define SNIPPET_DESIRED 1 /* We want to include this match in the snippet */
/*
** Generate the text of a snippet.
*/
static void snippetText(
fulltext_cursor *pCursor, /* The cursor we need the snippet for */
const char *zStartMark, /* Markup to appear before each match */
const char *zEndMark, /* Markup to appear after each match */
const char *zEllipsis /* Ellipsis mark */
){
int i, j;
struct snippetMatch *aMatch;
int nMatch;
int nDesired;
StringBuffer sb;
int tailCol;
int tailOffset;
int iCol;
int nDoc;
const char *zDoc;
int iStart, iEnd;
int tailEllipsis = 0;
int iMatch;
sqlite3_free(pCursor->snippet.zSnippet);
pCursor->snippet.zSnippet = 0;
aMatch = pCursor->snippet.aMatch;
nMatch = pCursor->snippet.nMatch;
initStringBuffer(&sb);
for(i=0; i<nMatch; i++){
aMatch[i].snStatus = SNIPPET_IGNORE;
}
nDesired = 0;
for(i=0; i<pCursor->q.nTerms; i++){
for(j=0; j<nMatch; j++){
if( aMatch[j].iTerm==i ){
aMatch[j].snStatus = SNIPPET_DESIRED;
nDesired++;
break;
}
}
}
iMatch = 0;
tailCol = -1;
tailOffset = 0;
for(i=0; i<nMatch && nDesired>0; i++){
if( aMatch[i].snStatus!=SNIPPET_DESIRED ) continue;
nDesired--;
iCol = aMatch[i].iCol;
zDoc = (const char*)sqlite3_column_text(pCursor->pStmt, iCol+1);
nDoc = sqlite3_column_bytes(pCursor->pStmt, iCol+1);
iStart = aMatch[i].iStart - 40;
iStart = wordBoundary(iStart, zDoc, nDoc, aMatch, nMatch, iCol);
if( iStart<=10 ){
iStart = 0;
}
if( iCol==tailCol && iStart<=tailOffset+20 ){
iStart = tailOffset;
}
if( (iCol!=tailCol && tailCol>=0) || iStart!=tailOffset ){
trimWhiteSpace(&sb);
appendWhiteSpace(&sb);
append(&sb, zEllipsis);
appendWhiteSpace(&sb);
}
iEnd = aMatch[i].iStart + aMatch[i].nByte + 40;
iEnd = wordBoundary(iEnd, zDoc, nDoc, aMatch, nMatch, iCol);
if( iEnd>=nDoc-10 ){
iEnd = nDoc;
tailEllipsis = 0;
}else{
tailEllipsis = 1;
}
while( iMatch<nMatch && aMatch[iMatch].iCol<iCol ){ iMatch++; }
while( iStart<iEnd ){
while( iMatch<nMatch && aMatch[iMatch].iStart<iStart
&& aMatch[iMatch].iCol<=iCol ){
iMatch++;
}
if( iMatch<nMatch && aMatch[iMatch].iStart<iEnd
&& aMatch[iMatch].iCol==iCol ){
nappend(&sb, &zDoc[iStart], aMatch[iMatch].iStart - iStart);
iStart = aMatch[iMatch].iStart;
append(&sb, zStartMark);
nappend(&sb, &zDoc[iStart], aMatch[iMatch].nByte);
append(&sb, zEndMark);
iStart += aMatch[iMatch].nByte;
for(j=iMatch+1; j<nMatch; j++){
if( aMatch[j].iTerm==aMatch[iMatch].iTerm
&& aMatch[j].snStatus==SNIPPET_DESIRED ){
nDesired--;
aMatch[j].snStatus = SNIPPET_IGNORE;
}
}
}else{
nappend(&sb, &zDoc[iStart], iEnd - iStart);
iStart = iEnd;
}
}
tailCol = iCol;
tailOffset = iEnd;
}
trimWhiteSpace(&sb);
if( tailEllipsis ){
appendWhiteSpace(&sb);
append(&sb, zEllipsis);
}
pCursor->snippet.zSnippet = stringBufferData(&sb);
pCursor->snippet.nSnippet = stringBufferLength(&sb);
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fulltextClose(sqlite3_vtab_cursor *pCursor){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
FTSTRACE(("FTS3 Close %p\n", c));
sqlite3_finalize(c->pStmt);
queryClear(&c->q);
snippetClear(&c->snippet);
if( c->result.nData!=0 ) dlrDestroy(&c->reader);
dataBufferDestroy(&c->result);
sqlite3_free(c);
return SQLITE_OK;
}
static int fulltextNext(sqlite3_vtab_cursor *pCursor){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
int rc;
FTSTRACE(("FTS3 Next %p\n", pCursor));
snippetClear(&c->snippet);
if( c->iCursorType < QUERY_FULLTEXT ){
/* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
rc = sqlite3_step(c->pStmt);
switch( rc ){
case SQLITE_ROW:
c->eof = 0;
return SQLITE_OK;
case SQLITE_DONE:
c->eof = 1;
return SQLITE_OK;
default:
c->eof = 1;
return rc;
}
} else { /* full-text query */
rc = sqlite3_reset(c->pStmt);
if( rc!=SQLITE_OK ) return rc;
if( c->result.nData==0 || dlrAtEnd(&c->reader) ){
c->eof = 1;
return SQLITE_OK;
}
rc = sqlite3_bind_int64(c->pStmt, 1, dlrDocid(&c->reader));
dlrStep(&c->reader);
if( rc!=SQLITE_OK ) return rc;
/* TODO(shess) Handle SQLITE_SCHEMA AND SQLITE_BUSY. */
rc = sqlite3_step(c->pStmt);
if( rc==SQLITE_ROW ){ /* the case we expect */
c->eof = 0;
return SQLITE_OK;
}
/* an error occurred; abort */
return rc==SQLITE_DONE ? SQLITE_ERROR : rc;
}
}
/* TODO(shess) If we pushed LeafReader to the top of the file, or to
** another file, term_select() could be pushed above
** docListOfTerm().
*/
static int termSelect(fulltext_vtab *v, int iColumn,
const char *pTerm, int nTerm, int isPrefix,
DocListType iType, DataBuffer *out);
/* Return a DocList corresponding to the query term *pTerm. If *pTerm
** is the first term of a phrase query, go ahead and evaluate the phrase
** query and return the doclist for the entire phrase query.
**
** The resulting DL_DOCIDS doclist is stored in pResult, which is
** overwritten.
*/
static int docListOfTerm(
fulltext_vtab *v, /* The full text index */
int iColumn, /* column to restrict to. No restriction if >=nColumn */
QueryTerm *pQTerm, /* Term we are looking for, or 1st term of a phrase */
sqlite-amalgamation.c view on Meta::CPAN
/* Add a new term pTerm[0..nTerm-1] to the query *q.
*/
static void queryAdd(Query *q, const char *pTerm, int nTerm){
QueryTerm *t;
++q->nTerms;
q->pTerms = sqlite3_realloc(q->pTerms, q->nTerms * sizeof(q->pTerms[0]));
if( q->pTerms==0 ){
q->nTerms = 0;
return;
}
t = &q->pTerms[q->nTerms - 1];
CLEAR(t);
t->pTerm = sqlite3_malloc(nTerm+1);
memcpy(t->pTerm, pTerm, nTerm);
t->pTerm[nTerm] = 0;
t->nTerm = nTerm;
t->isOr = q->nextIsOr;
t->isPrefix = 0;
q->nextIsOr = 0;
t->iColumn = q->nextColumn;
q->nextColumn = q->dfltColumn;
}
/*
** Check to see if the string zToken[0...nToken-1] matches any
** column name in the virtual table. If it does,
** return the zero-indexed column number. If not, return -1.
*/
static int checkColumnSpecifier(
fulltext_vtab *pVtab, /* The virtual table */
const char *zToken, /* Text of the token */
int nToken /* Number of characters in the token */
){
int i;
for(i=0; i<pVtab->nColumn; i++){
if( memcmp(pVtab->azColumn[i], zToken, nToken)==0
&& pVtab->azColumn[i][nToken]==0 ){
return i;
}
}
return -1;
}
/*
** Parse the text at pSegment[0..nSegment-1]. Add additional terms
** to the query being assemblied in pQuery.
**
** inPhrase is true if pSegment[0..nSegement-1] is contained within
** double-quotes. If inPhrase is true, then the first term
** is marked with the number of terms in the phrase less one and
** OR and "-" syntax is ignored. If inPhrase is false, then every
** term found is marked with nPhrase=0 and OR and "-" syntax is significant.
*/
static int tokenizeSegment(
sqlite3_tokenizer *pTokenizer, /* The tokenizer to use */
const char *pSegment, int nSegment, /* Query expression being parsed */
int inPhrase, /* True if within "..." */
Query *pQuery /* Append results here */
){
const sqlite3_tokenizer_module *pModule = pTokenizer->pModule;
sqlite3_tokenizer_cursor *pCursor;
int firstIndex = pQuery->nTerms;
int iCol;
int nTerm = 1;
int rc = pModule->xOpen(pTokenizer, pSegment, nSegment, &pCursor);
if( rc!=SQLITE_OK ) return rc;
pCursor->pTokenizer = pTokenizer;
while( 1 ){
const char *pToken;
int nToken, iBegin, iEnd, iPos;
rc = pModule->xNext(pCursor,
&pToken, &nToken,
&iBegin, &iEnd, &iPos);
if( rc!=SQLITE_OK ) break;
if( !inPhrase &&
pSegment[iEnd]==':' &&
(iCol = checkColumnSpecifier(pQuery->pFts, pToken, nToken))>=0 ){
pQuery->nextColumn = iCol;
continue;
}
if( !inPhrase && pQuery->nTerms>0 && nToken==2
&& pSegment[iBegin+0]=='O'
&& pSegment[iBegin+1]=='R'
){
pQuery->nextIsOr = 1;
continue;
}
if( !inPhrase && pQuery->nTerms>0 && !pQuery->nextIsOr && nToken==4
&& pSegment[iBegin+0]=='N'
&& pSegment[iBegin+1]=='E'
&& pSegment[iBegin+2]=='A'
&& pSegment[iBegin+3]=='R'
){
QueryTerm *pTerm = &pQuery->pTerms[pQuery->nTerms-1];
if( (iBegin+6)<nSegment
&& pSegment[iBegin+4] == '/'
&& pSegment[iBegin+5]>='0' && pSegment[iBegin+5]<='9'
){
pTerm->nNear = (pSegment[iBegin+5] - '0');
nToken += 2;
if( pSegment[iBegin+6]>='0' && pSegment[iBegin+6]<=9 ){
pTerm->nNear = pTerm->nNear * 10 + (pSegment[iBegin+6] - '0');
iEnd++;
}
pModule->xNext(pCursor, &pToken, &nToken, &iBegin, &iEnd, &iPos);
} else {
pTerm->nNear = SQLITE_FTS3_DEFAULT_NEAR_PARAM;
}
pTerm->nNear++;
continue;
}
queryAdd(pQuery, pToken, nToken);
if( !inPhrase && iBegin>0 && pSegment[iBegin-1]=='-' ){
pQuery->pTerms[pQuery->nTerms-1].isNot = 1;
}
if( iEnd<nSegment && pSegment[iEnd]=='*' ){
pQuery->pTerms[pQuery->nTerms-1].isPrefix = 1;
sqlite-amalgamation.c view on Meta::CPAN
return rc;
}
dataBufferInit(&new, 0);
docListOrMerge(right.pData, right.nData, or.pData, or.nData, &new);
dataBufferDestroy(&right);
dataBufferDestroy(&or);
right = new;
}
if( i==nNot ){ /* first term processed. */
left = right;
}else{
dataBufferInit(&new, 0);
docListAndMerge(left.pData, left.nData, right.pData, right.nData, &new);
dataBufferDestroy(&right);
dataBufferDestroy(&left);
left = new;
}
}
if( nNot==pQuery->nTerms ){
/* We do not yet know how to handle a query of only NOT terms */
return SQLITE_ERROR;
}
/* Do the EXCEPT terms */
for(i=0; i<pQuery->nTerms; i += aTerm[i].nPhrase + 1){
if( !aTerm[i].isNot ) continue;
rc = docListOfTerm(v, aTerm[i].iColumn, &aTerm[i], &right);
if( rc ){
queryClear(pQuery);
dataBufferDestroy(&left);
return rc;
}
dataBufferInit(&new, 0);
docListExceptMerge(left.pData, left.nData, right.pData, right.nData, &new);
dataBufferDestroy(&right);
dataBufferDestroy(&left);
left = new;
}
*pResult = left;
return rc;
}
/*
** This is the xFilter interface for the virtual table. See
** the virtual table xFilter method documentation for additional
** information.
**
** If idxNum==QUERY_GENERIC then do a full table scan against
** the %_content table.
**
** If idxNum==QUERY_DOCID then do a docid lookup for a single entry
** in the %_content table.
**
** If idxNum>=QUERY_FULLTEXT then use the full text index. The
** column on the left-hand side of the MATCH operator is column
** number idxNum-QUERY_FULLTEXT, 0 indexed. argv[0] is the right-hand
** side of the MATCH operator.
*/
/* TODO(shess) Upgrade the cursor initialization and destruction to
** account for fulltextFilter() being called multiple times on the
** same cursor. The current solution is very fragile. Apply fix to
** fts3 as appropriate.
*/
static int fulltextFilter(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, const char *idxStr, /* Which indexing scheme to use */
int argc, sqlite3_value **argv /* Arguments for the indexing scheme */
){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
fulltext_vtab *v = cursor_vtab(c);
int rc;
FTSTRACE(("FTS3 Filter %p\n",pCursor));
/* If the cursor has a statement that was not prepared according to
** idxNum, clear it. I believe all calls to fulltextFilter with a
** given cursor will have the same idxNum , but in this case it's
** easy to be safe.
*/
if( c->pStmt && c->iCursorType!=idxNum ){
sqlite3_finalize(c->pStmt);
c->pStmt = NULL;
}
/* Get a fresh statement appropriate to idxNum. */
/* TODO(shess): Add a prepared-statement cache in the vt structure.
** The cache must handle multiple open cursors. Easier to cache the
** statement variants at the vt to reduce malloc/realloc/free here.
** Or we could have a StringBuffer variant which allowed stack
** construction for small values.
*/
if( !c->pStmt ){
StringBuffer sb;
initStringBuffer(&sb);
append(&sb, "SELECT docid, ");
appendList(&sb, v->nColumn, v->azContentColumn);
append(&sb, " FROM %_content");
if( idxNum!=QUERY_GENERIC ) append(&sb, " WHERE docid = ?");
rc = sql_prepare(v->db, v->zDb, v->zName, &c->pStmt,
stringBufferData(&sb));
stringBufferDestroy(&sb);
if( rc!=SQLITE_OK ) return rc;
c->iCursorType = idxNum;
}else{
sqlite3_reset(c->pStmt);
assert( c->iCursorType==idxNum );
}
switch( idxNum ){
case QUERY_GENERIC:
break;
case QUERY_DOCID:
rc = sqlite3_bind_int64(c->pStmt, 1, sqlite3_value_int64(argv[0]));
if( rc!=SQLITE_OK ) return rc;
break;
default: /* full-text search */
{
const char *zQuery = (const char *)sqlite3_value_text(argv[0]);
assert( idxNum<=QUERY_FULLTEXT+v->nColumn);
assert( argc==1 );
queryClear(&c->q);
if( c->result.nData!=0 ){
/* This case happens if the same cursor is used repeatedly. */
dlrDestroy(&c->reader);
dataBufferReset(&c->result);
}else{
dataBufferInit(&c->result, 0);
}
rc = fulltextQuery(v, idxNum-QUERY_FULLTEXT, zQuery, -1, &c->result, &c->q);
if( rc!=SQLITE_OK ) return rc;
if( c->result.nData!=0 ){
dlrInit(&c->reader, DL_DOCIDS, c->result.pData, c->result.nData);
}
break;
}
}
return fulltextNext(pCursor);
}
/* This is the xEof method of the virtual table. The SQLite core
** calls this routine to find out if it has reached the end of
** a query's results set.
*/
static int fulltextEof(sqlite3_vtab_cursor *pCursor){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
return c->eof;
}
/* This is the xColumn method of the virtual table. The SQLite
** core calls this method during a query when it needs the value
** of a column from the virtual table. This method needs to use
** one of the sqlite3_result_*() routines to store the requested
** value back in the pContext.
*/
static int fulltextColumn(sqlite3_vtab_cursor *pCursor,
sqlite3_context *pContext, int idxCol){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
fulltext_vtab *v = cursor_vtab(c);
if( idxCol<v->nColumn ){
sqlite3_value *pVal = sqlite3_column_value(c->pStmt, idxCol+1);
sqlite3_result_value(pContext, pVal);
}else if( idxCol==v->nColumn ){
/* The extra column whose name is the same as the table.
** Return a blob which is a pointer to the cursor
*/
sqlite3_result_blob(pContext, &c, sizeof(c), SQLITE_TRANSIENT);
}else if( idxCol==v->nColumn+1 ){
/* The docid column, which is an alias for rowid. */
sqlite3_value *pVal = sqlite3_column_value(c->pStmt, 0);
sqlite3_result_value(pContext, pVal);
}
return SQLITE_OK;
}
/* This is the xRowid method. The SQLite core calls this routine to
** retrieve the rowid for the current row of the result set. fts3
** exposes %_content.docid as the rowid for the virtual table. The
** rowid should be written to *pRowid.
*/
static int fulltextRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
fulltext_cursor *c = (fulltext_cursor *) pCursor;
*pRowid = sqlite3_column_int64(c->pStmt, 0);
return SQLITE_OK;
}
/* Add all terms in [zText] to pendingTerms table. If [iColumn] > 0,
** we also store positions and offsets in the hash table using that
** column number.
*/
static int buildTerms(fulltext_vtab *v, sqlite_int64 iDocid,
const char *zText, int iColumn){
sqlite3_tokenizer *pTokenizer = v->pTokenizer;
sqlite3_tokenizer_cursor *pCursor;
const char *pToken;
int nTokenBytes;
int iStartOffset, iEndOffset, iPosition;
int rc;
rc = pTokenizer->pModule->xOpen(pTokenizer, zText, -1, &pCursor);
if( rc!=SQLITE_OK ) return rc;
pCursor->pTokenizer = pTokenizer;
while( SQLITE_OK==(rc=pTokenizer->pModule->xNext(pCursor,
&pToken, &nTokenBytes,
&iStartOffset, &iEndOffset,
&iPosition)) ){
DLCollector *p;
int nData; /* Size of doclist before our update. */
/* Positions can't be negative; we use -1 as a terminator
* internally. Token can't be NULL or empty. */
if( iPosition<0 || pToken == NULL || nTokenBytes == 0 ){
rc = SQLITE_ERROR;
break;
}
p = fts3HashFind(&v->pendingTerms, pToken, nTokenBytes);
if( p==NULL ){
nData = 0;
p = dlcNew(iDocid, DL_DEFAULT);
fts3HashInsert(&v->pendingTerms, pToken, nTokenBytes, p);
/* Overhead for our hash table entry, the key, and the value. */
v->nPendingData += sizeof(struct fts3HashElem)+sizeof(*p)+nTokenBytes;
}else{
nData = p->b.nData;
if( p->dlw.iPrevDocid!=iDocid ) dlcNext(p, iDocid);
}
if( iColumn>=0 ){
dlcAddPos(p, iColumn, iPosition, iStartOffset, iEndOffset);
}
/* Accumulate data added by dlcNew or dlcNext, and dlcAddPos. */
v->nPendingData += p->b.nData-nData;
}
/* TODO(shess) Check return? Should this be able to cause errors at
** this point? Actually, same question about sqlite3_finalize(),
** though one could argue that failure there means that the data is
** not durable. *ponder*
*/
pTokenizer->pModule->xClose(pCursor);
if( SQLITE_DONE == rc ) return SQLITE_OK;
return rc;
}
/* Add doclists for all terms in [pValues] to pendingTerms table. */
static int insertTerms(fulltext_vtab *v, sqlite_int64 iDocid,
sqlite3_value **pValues){
int i;
for(i = 0; i < v->nColumn ; ++i){
char *zText = (char*)sqlite3_value_text(pValues[i]);
int rc = buildTerms(v, iDocid, zText, i);
sqlite-amalgamation.c view on Meta::CPAN
*/
ASSERT_VALID_INTERIOR_BLOCK(block);
rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
if( rc!=SQLITE_OK ) return rc;
*piEndBlockid = iBlockid;
pWriter->parentWriter = sqlite3_malloc(sizeof(*pWriter->parentWriter));
interiorWriterInit(pWriter->iHeight+1,
block->term.pData, block->term.nData,
iBlockid, pWriter->parentWriter);
/* Flush additional blocks and append to the higher interior
** node.
*/
for(block=block->next; block!=NULL; block=block->next){
ASSERT_VALID_INTERIOR_BLOCK(block);
rc = block_insert(v, block->data.pData, block->data.nData, &iBlockid);
if( rc!=SQLITE_OK ) return rc;
*piEndBlockid = iBlockid;
interiorWriterAppend(pWriter->parentWriter,
block->term.pData, block->term.nData, iBlockid);
}
/* Parent node gets the chance to be the root. */
return interiorWriterRootInfo(v, pWriter->parentWriter,
ppRootInfo, pnRootInfo, piEndBlockid);
}
/****************************************************************/
/* InteriorReader is used to read off the data from an interior node
** (see comment at top of file for the format).
*/
typedef struct InteriorReader {
const char *pData;
int nData;
DataBuffer term; /* previous term, for decoding term delta. */
sqlite_int64 iBlockid;
} InteriorReader;
static void interiorReaderDestroy(InteriorReader *pReader){
dataBufferDestroy(&pReader->term);
SCRAMBLE(pReader);
}
/* TODO(shess) The assertions are great, but what if we're in NDEBUG
** and the blob is empty or otherwise contains suspect data?
*/
static void interiorReaderInit(const char *pData, int nData,
InteriorReader *pReader){
int n, nTerm;
/* Require at least the leading flag byte */
assert( nData>0 );
assert( pData[0]!='\0' );
CLEAR(pReader);
/* Decode the base blockid, and set the cursor to the first term. */
n = fts3GetVarint(pData+1, &pReader->iBlockid);
assert( 1+n<=nData );
pReader->pData = pData+1+n;
pReader->nData = nData-(1+n);
/* A single-child interior node (such as when a leaf node was too
** large for the segment directory) won't have any terms.
** Otherwise, decode the first term.
*/
if( pReader->nData==0 ){
dataBufferInit(&pReader->term, 0);
}else{
n = fts3GetVarint32(pReader->pData, &nTerm);
dataBufferInit(&pReader->term, nTerm);
dataBufferReplace(&pReader->term, pReader->pData+n, nTerm);
assert( n+nTerm<=pReader->nData );
pReader->pData += n+nTerm;
pReader->nData -= n+nTerm;
}
}
static int interiorReaderAtEnd(InteriorReader *pReader){
return pReader->term.nData==0;
}
static sqlite_int64 interiorReaderCurrentBlockid(InteriorReader *pReader){
return pReader->iBlockid;
}
static int interiorReaderTermBytes(InteriorReader *pReader){
assert( !interiorReaderAtEnd(pReader) );
return pReader->term.nData;
}
static const char *interiorReaderTerm(InteriorReader *pReader){
assert( !interiorReaderAtEnd(pReader) );
return pReader->term.pData;
}
/* Step forward to the next term in the node. */
static void interiorReaderStep(InteriorReader *pReader){
assert( !interiorReaderAtEnd(pReader) );
/* If the last term has been read, signal eof, else construct the
** next term.
*/
if( pReader->nData==0 ){
dataBufferReset(&pReader->term);
}else{
int n, nPrefix, nSuffix;
n = fts3GetVarint32(pReader->pData, &nPrefix);
n += fts3GetVarint32(pReader->pData+n, &nSuffix);
/* Truncate the current term and append suffix data. */
pReader->term.nData = nPrefix;
dataBufferAppend(&pReader->term, pReader->pData+n, nSuffix);
assert( n+nSuffix<=pReader->nData );
pReader->pData += n+nSuffix;
pReader->nData -= n+nSuffix;
sqlite-amalgamation.c view on Meta::CPAN
assert( nArg==2+v->nColumn+2);
if( SQLITE_NULL != sqlite3_value_type(pRequestDocid) &&
SQLITE_NULL != sqlite3_value_type(ppArg[1]) ){
/* TODO(shess) Consider allowing this to work if the values are
** identical. I'm inclined to discourage that usage, though,
** given that both rowid and docid are special columns. Better
** would be to define one or the other as the default winner,
** but should it be fts3-centric (docid) or SQLite-centric
** (rowid)?
*/
rc = SQLITE_ERROR;
}else{
if( SQLITE_NULL == sqlite3_value_type(pRequestDocid) ){
pRequestDocid = ppArg[1];
}
rc = index_insert(v, pRequestDocid, &ppArg[2], pRowid);
}
}
return rc;
}
static int fulltextSync(sqlite3_vtab *pVtab){
FTSTRACE(("FTS3 xSync()\n"));
return flushPendingTerms((fulltext_vtab *)pVtab);
}
static int fulltextBegin(sqlite3_vtab *pVtab){
fulltext_vtab *v = (fulltext_vtab *) pVtab;
FTSTRACE(("FTS3 xBegin()\n"));
/* Any buffered updates should have been cleared by the previous
** transaction.
*/
assert( v->nPendingData<0 );
return clearPendingTerms(v);
}
static int fulltextCommit(sqlite3_vtab *pVtab){
fulltext_vtab *v = (fulltext_vtab *) pVtab;
FTSTRACE(("FTS3 xCommit()\n"));
/* Buffered updates should have been cleared by fulltextSync(). */
assert( v->nPendingData<0 );
return clearPendingTerms(v);
}
static int fulltextRollback(sqlite3_vtab *pVtab){
FTSTRACE(("FTS3 xRollback()\n"));
return clearPendingTerms((fulltext_vtab *)pVtab);
}
/*
** Implementation of the snippet() function for FTS3
*/
static void snippetFunc(
sqlite3_context *pContext,
int argc,
sqlite3_value **argv
){
fulltext_cursor *pCursor;
if( argc<1 ) return;
if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
sqlite3_result_error(pContext, "illegal first argument to html_snippet",-1);
}else{
const char *zStart = "<b>";
const char *zEnd = "</b>";
const char *zEllipsis = "<b>...</b>";
memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
if( argc>=2 ){
zStart = (const char*)sqlite3_value_text(argv[1]);
if( argc>=3 ){
zEnd = (const char*)sqlite3_value_text(argv[2]);
if( argc>=4 ){
zEllipsis = (const char*)sqlite3_value_text(argv[3]);
}
}
}
snippetAllOffsets(pCursor);
snippetText(pCursor, zStart, zEnd, zEllipsis);
sqlite3_result_text(pContext, pCursor->snippet.zSnippet,
pCursor->snippet.nSnippet, SQLITE_STATIC);
}
}
/*
** Implementation of the offsets() function for FTS3
*/
static void snippetOffsetsFunc(
sqlite3_context *pContext,
int argc,
sqlite3_value **argv
){
fulltext_cursor *pCursor;
if( argc<1 ) return;
if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
sqlite3_result_error(pContext, "illegal first argument to offsets",-1);
}else{
memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
snippetAllOffsets(pCursor);
snippetOffsetText(&pCursor->snippet);
sqlite3_result_text(pContext,
pCursor->snippet.zOffset, pCursor->snippet.nOffset,
SQLITE_STATIC);
}
}
/* OptLeavesReader is nearly identical to LeavesReader, except that
** where LeavesReader is geared towards the merging of complete
** segment levels (with exactly MERGE_COUNT segments), OptLeavesReader
** is geared towards implementation of the optimize() function, and
** can merge all segments simultaneously. This version may be
** somewhat less efficient than LeavesReader because it merges into an
** accumulator rather than doing an N-way merge, but since segment
** size grows exponentially (so segment count logrithmically) this is
** probably not an immediate problem.
*/
/* TODO(shess): Prove that assertion, or extend the merge code to
** merge tree fashion (like the prefix-searching code does).
*/
/* TODO(shess): OptLeavesReader and LeavesReader could probably be
** merged with little or no loss of performance for LeavesReader. The
** merged code would need to handle >MERGE_COUNT segments, and would
** also need to be able to optionally optimize away deletes.
*/
typedef struct OptLeavesReader {
/* Segment number, to order readers by age. */
int segment;
LeavesReader reader;
} OptLeavesReader;
static int optLeavesReaderAtEnd(OptLeavesReader *pReader){
return leavesReaderAtEnd(&pReader->reader);
}
static int optLeavesReaderTermBytes(OptLeavesReader *pReader){
return leavesReaderTermBytes(&pReader->reader);
}
static const char *optLeavesReaderData(OptLeavesReader *pReader){
return leavesReaderData(&pReader->reader);
}
static int optLeavesReaderDataBytes(OptLeavesReader *pReader){
return leavesReaderDataBytes(&pReader->reader);
}
static const char *optLeavesReaderTerm(OptLeavesReader *pReader){
return leavesReaderTerm(&pReader->reader);
}
static int optLeavesReaderStep(fulltext_vtab *v, OptLeavesReader *pReader){
return leavesReaderStep(v, &pReader->reader);
}
static int optLeavesReaderTermCmp(OptLeavesReader *lr1, OptLeavesReader *lr2){
return leavesReaderTermCmp(&lr1->reader, &lr2->reader);
}
/* Order by term ascending, segment ascending (oldest to newest), with
sqlite-amalgamation.c view on Meta::CPAN
iReader++, nReaders++ ){
dlrInit(&dlReaders[nReaders], DL_DEFAULT,
optLeavesReaderData(&readers[iReader]),
optLeavesReaderDataBytes(&readers[iReader]));
}
/* Merge doclists and swap result into accumulator. */
dataBufferReset(&merged);
docListMerge(&merged, dlReaders, nReaders);
tmp = merged;
merged = doclist;
doclist = tmp;
while( nReaders-- > 0 ){
dlrDestroy(&dlReaders[nReaders]);
}
/* Accumulated doclist to reader 0 for next pass. */
dlrInit(&dlReaders[0], DL_DEFAULT, doclist.pData, doclist.nData);
}
/* Destroy reader that was left in the pipeline. */
dlrDestroy(&dlReaders[0]);
/* Trim deletions from the doclist. */
dataBufferReset(&merged);
docListTrim(DL_DEFAULT, doclist.pData, doclist.nData,
-1, DL_DEFAULT, &merged);
}
/* Only pass doclists with hits (skip if all hits deleted). */
if( merged.nData>0 ){
rc = leafWriterStep(v, pWriter,
optLeavesReaderTerm(&readers[0]),
optLeavesReaderTermBytes(&readers[0]),
merged.pData, merged.nData);
if( rc!=SQLITE_OK ) goto err;
}
/* Step merged readers to next term and reorder. */
while( i-- > 0 ){
rc = optLeavesReaderStep(v, &readers[i]);
if( rc!=SQLITE_OK ) goto err;
optLeavesReaderReorder(&readers[i], nReaders-i);
}
}
err:
dataBufferDestroy(&doclist);
dataBufferDestroy(&merged);
return rc;
}
/* Implement optimize() function for FTS3. optimize(t) merges all
** segments in the fts index into a single segment. 't' is the magic
** table-named column.
*/
static void optimizeFunc(sqlite3_context *pContext,
int argc, sqlite3_value **argv){
fulltext_cursor *pCursor;
if( argc>1 ){
sqlite3_result_error(pContext, "excess arguments to optimize()",-1);
}else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
sqlite3_result_error(pContext, "illegal first argument to optimize",-1);
}else{
fulltext_vtab *v;
int i, rc, iMaxLevel;
OptLeavesReader *readers;
int nReaders;
LeafWriter writer;
sqlite3_stmt *s;
memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
v = cursor_vtab(pCursor);
/* Flush any buffered updates before optimizing. */
rc = flushPendingTerms(v);
if( rc!=SQLITE_OK ) goto err;
rc = segdir_count(v, &nReaders, &iMaxLevel);
if( rc!=SQLITE_OK ) goto err;
if( nReaders==0 || nReaders==1 ){
sqlite3_result_text(pContext, "Index already optimal", -1,
SQLITE_STATIC);
return;
}
rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
if( rc!=SQLITE_OK ) goto err;
readers = sqlite3_malloc(nReaders*sizeof(readers[0]));
if( readers==NULL ) goto err;
/* Note that there will already be a segment at this position
** until we call segdir_delete() on iMaxLevel.
*/
leafWriterInit(iMaxLevel, 0, &writer);
i = 0;
while( (rc = sqlite3_step(s))==SQLITE_ROW ){
sqlite_int64 iStart = sqlite3_column_int64(s, 0);
sqlite_int64 iEnd = sqlite3_column_int64(s, 1);
const char *pRootData = sqlite3_column_blob(s, 2);
int nRootData = sqlite3_column_bytes(s, 2);
assert( i<nReaders );
rc = leavesReaderInit(v, -1, iStart, iEnd, pRootData, nRootData,
&readers[i].reader);
if( rc!=SQLITE_OK ) break;
readers[i].segment = i;
i++;
}
/* If we managed to succesfully read them all, optimize them. */
if( rc==SQLITE_DONE ){
assert( i==nReaders );
rc = optimizeInternal(v, readers, nReaders, &writer);
}
while( i-- > 0 ){
leavesReaderDestroy(&readers[i].reader);
}
sqlite3_free(readers);
/* If we've successfully gotten to here, delete the old segments
** and flush the interior structure of the new segment.
*/
if( rc==SQLITE_OK ){
for( i=0; i<=iMaxLevel; i++ ){
rc = segdir_delete(v, i);
if( rc!=SQLITE_OK ) break;
}
sqlite-amalgamation.c view on Meta::CPAN
int iTerm, nTerms, nResultBytes, iByte;
char *result;
TermData *pData;
fts3HashElem *e;
/* Iterate pTerms to generate an array of terms in pData for
** sorting.
*/
nTerms = fts3HashCount(pTerms);
assert( nTerms>0 );
pData = sqlite3_malloc(nTerms*sizeof(TermData));
if( pData==NULL ) return SQLITE_NOMEM;
nResultBytes = 0;
for(iTerm = 0, e = fts3HashFirst(pTerms); e; iTerm++, e = fts3HashNext(e)){
nResultBytes += fts3HashKeysize(e)+1; /* Term plus trailing space */
assert( iTerm<nTerms );
pData[iTerm].pTerm = fts3HashKey(e);
pData[iTerm].nTerm = fts3HashKeysize(e);
pData[iTerm].pCollector = fts3HashData(e); /* unused */
}
assert( iTerm==nTerms );
assert( nResultBytes>0 ); /* nTerms>0, nResultsBytes must be, too. */
result = sqlite3_malloc(nResultBytes);
if( result==NULL ){
sqlite3_free(pData);
return SQLITE_NOMEM;
}
if( nTerms>1 ) qsort(pData, nTerms, sizeof(*pData), termDataCmp);
/* Read the terms in order to build the result. */
iByte = 0;
for(iTerm=0; iTerm<nTerms; ++iTerm){
memcpy(result+iByte, pData[iTerm].pTerm, pData[iTerm].nTerm);
iByte += pData[iTerm].nTerm;
result[iByte++] = ' ';
}
assert( iByte==nResultBytes );
assert( result[nResultBytes-1]==' ' );
result[nResultBytes-1] = '\0';
/* Passes away ownership of result. */
sqlite3_result_text(pContext, result, nResultBytes-1, sqlite3_free);
sqlite3_free(pData);
return SQLITE_OK;
}
/* Implements dump_terms() for use in inspecting the fts3 index from
** tests. TEXT result containing the ordered list of terms joined by
** spaces. dump_terms(t, level, idx) dumps the terms for the segment
** specified by level, idx (in %_segdir), while dump_terms(t) dumps
** all terms in the index. In both cases t is the fts table's magic
** table-named column.
*/
static void dumpTermsFunc(
sqlite3_context *pContext,
int argc, sqlite3_value **argv
){
fulltext_cursor *pCursor;
if( argc!=3 && argc!=1 ){
generateError(pContext, "dump_terms", "incorrect arguments");
}else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
generateError(pContext, "dump_terms", "illegal first argument");
}else{
fulltext_vtab *v;
fts3Hash terms;
sqlite3_stmt *s = NULL;
int rc;
memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
v = cursor_vtab(pCursor);
/* If passed only the cursor column, get all segments. Otherwise
** get the segment described by the following two arguments.
*/
if( argc==1 ){
rc = sql_get_statement(v, SEGDIR_SELECT_ALL_STMT, &s);
}else{
rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
if( rc==SQLITE_OK ){
rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[1]));
if( rc==SQLITE_OK ){
rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[2]));
}
}
}
if( rc!=SQLITE_OK ){
generateError(pContext, "dump_terms", NULL);
return;
}
/* Collect the terms for each segment. */
sqlite3Fts3HashInit(&terms, FTS3_HASH_STRING, 1);
while( (rc = sqlite3_step(s))==SQLITE_ROW ){
rc = collectSegmentTerms(v, s, &terms);
if( rc!=SQLITE_OK ) break;
}
if( rc!=SQLITE_DONE ){
sqlite3_reset(s);
generateError(pContext, "dump_terms", NULL);
}else{
const int nTerms = fts3HashCount(&terms);
if( nTerms>0 ){
rc = generateTermsResult(pContext, &terms);
if( rc==SQLITE_NOMEM ){
generateError(pContext, "dump_terms", "out of memory");
}else{
assert( rc==SQLITE_OK );
}
}else if( argc==3 ){
/* The specific segment asked for could not be found. */
generateError(pContext, "dump_terms", "segment not found");
}else{
/* No segments found. */
/* TODO(shess): It should be impossible to reach this. This
** case can only happen for an empty table, in which case
** SQLite has no rows to call this function on.
*/
sqlite3_result_null(pContext);
}
}
sqlite3Fts3HashClear(&terms);
}
}
/* Expand the DL_DEFAULT doclist in pData into a text result in
** pContext.
*/
static void createDoclistResult(sqlite3_context *pContext,
const char *pData, int nData){
DataBuffer dump;
sqlite-amalgamation.c view on Meta::CPAN
dataBufferAppend(&dump, buf, strlen(buf));
}
if( DL_DEFAULT==DL_POSITIONS_OFFSETS ){
sqlite3_snprintf(sizeof(buf), buf, "%d,%d,%d ",
plrPosition(&plReader),
plrStartOffset(&plReader), plrEndOffset(&plReader));
}else if( DL_DEFAULT==DL_POSITIONS ){
sqlite3_snprintf(sizeof(buf), buf, "%d ", plrPosition(&plReader));
}else{
assert( NULL=="Unhandled DL_DEFAULT value");
}
dataBufferAppend(&dump, buf, strlen(buf));
}
plrDestroy(&plReader);
assert( dump.nData>0 );
dump.nData--; /* Overwrite trailing space. */
assert( dump.pData[dump.nData]==' ');
dataBufferAppend(&dump, "]] ", 3);
}
}
dlrDestroy(&dlReader);
assert( dump.nData>0 );
dump.nData--; /* Overwrite trailing space. */
assert( dump.pData[dump.nData]==' ');
dump.pData[dump.nData] = '\0';
assert( dump.nData>0 );
/* Passes ownership of dump's buffer to pContext. */
sqlite3_result_text(pContext, dump.pData, dump.nData, sqlite3_free);
dump.pData = NULL;
dump.nData = dump.nCapacity = 0;
}
/* Implements dump_doclist() for use in inspecting the fts3 index from
** tests. TEXT result containing a string representation of the
** doclist for the indicated term. dump_doclist(t, term, level, idx)
** dumps the doclist for term from the segment specified by level, idx
** (in %_segdir), while dump_doclist(t, term) dumps the logical
** doclist for the term across all segments. The per-segment doclist
** can contain deletions, while the full-index doclist will not
** (deletions are omitted).
**
** Result formats differ with the setting of DL_DEFAULTS. Examples:
**
** DL_DOCIDS: [1] [3] [7]
** DL_POSITIONS: [1 0[0 4] 1[17]] [3 1[5]]
** DL_POSITIONS_OFFSETS: [1 0[0,0,3 4,23,26] 1[17,102,105]] [3 1[5,20,23]]
**
** In each case the number after the outer '[' is the docid. In the
** latter two cases, the number before the inner '[' is the column
** associated with the values within. For DL_POSITIONS the numbers
** within are the positions, for DL_POSITIONS_OFFSETS they are the
** position, the start offset, and the end offset.
*/
static void dumpDoclistFunc(
sqlite3_context *pContext,
int argc, sqlite3_value **argv
){
fulltext_cursor *pCursor;
if( argc!=2 && argc!=4 ){
generateError(pContext, "dump_doclist", "incorrect arguments");
}else if( sqlite3_value_type(argv[0])!=SQLITE_BLOB ||
sqlite3_value_bytes(argv[0])!=sizeof(pCursor) ){
generateError(pContext, "dump_doclist", "illegal first argument");
}else if( sqlite3_value_text(argv[1])==NULL ||
sqlite3_value_text(argv[1])[0]=='\0' ){
generateError(pContext, "dump_doclist", "empty second argument");
}else{
const char *pTerm = (const char *)sqlite3_value_text(argv[1]);
const int nTerm = strlen(pTerm);
fulltext_vtab *v;
int rc;
DataBuffer doclist;
memcpy(&pCursor, sqlite3_value_blob(argv[0]), sizeof(pCursor));
v = cursor_vtab(pCursor);
dataBufferInit(&doclist, 0);
/* termSelect() yields the same logical doclist that queries are
** run against.
*/
if( argc==2 ){
rc = termSelect(v, v->nColumn, pTerm, nTerm, 0, DL_DEFAULT, &doclist);
}else{
sqlite3_stmt *s = NULL;
/* Get our specific segment's information. */
rc = sql_get_statement(v, SEGDIR_SELECT_SEGMENT_STMT, &s);
if( rc==SQLITE_OK ){
rc = sqlite3_bind_int(s, 1, sqlite3_value_int(argv[2]));
if( rc==SQLITE_OK ){
rc = sqlite3_bind_int(s, 2, sqlite3_value_int(argv[3]));
}
}
if( rc==SQLITE_OK ){
rc = sqlite3_step(s);
if( rc==SQLITE_DONE ){
dataBufferDestroy(&doclist);
generateError(pContext, "dump_doclist", "segment not found");
return;
}
/* Found a segment, load it into doclist. */
if( rc==SQLITE_ROW ){
const sqlite_int64 iLeavesEnd = sqlite3_column_int64(s, 1);
const char *pData = sqlite3_column_blob(s, 2);
const int nData = sqlite3_column_bytes(s, 2);
/* loadSegment() is used by termSelect() to load each
** segment's data.
*/
rc = loadSegment(v, pData, nData, iLeavesEnd, pTerm, nTerm, 0,
&doclist);
if( rc==SQLITE_OK ){
rc = sqlite3_step(s);
/* Should not have more than one matching segment. */
if( rc!=SQLITE_DONE ){
sqlite3_reset(s);
dataBufferDestroy(&doclist);
generateError(pContext, "dump_doclist", "invalid segdir");
return;
}
rc = SQLITE_OK;
}
}
}
sqlite3_reset(s);
}
if( rc==SQLITE_OK ){
if( doclist.nData>0 ){
sqlite-amalgamation.c view on Meta::CPAN
if( pH->htsize==0 ){
fts3Rehash(pH,8);
if( pH->htsize==0 ){
pH->count = 0;
fts3HashFree(new_elem);
return data;
}
}
if( pH->count > pH->htsize ){
fts3Rehash(pH,pH->htsize*2);
}
assert( pH->htsize>0 );
assert( (pH->htsize & (pH->htsize-1))==0 );
h = hraw & (pH->htsize-1);
fts3HashInsertElement(pH, &pH->ht[h], new_elem);
new_elem->data = data;
return 0;
}
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
/************** End of fts3_hash.c *******************************************/
/************** Begin file fts3_porter.c *************************************/
/*
** 2006 September 30
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
*************************************************************************
** Implementation of the full-text-search tokenizer that implements
** a Porter stemmer.
*/
/*
** The code in this file is only compiled if:
**
** * The FTS3 module is being built as an extension
** (in which case SQLITE_CORE is not defined), or
**
** * The FTS3 module is being built into the core of
** SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
*/
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
/*
** Class derived from sqlite3_tokenizer
*/
typedef struct porter_tokenizer {
sqlite3_tokenizer base; /* Base class */
} porter_tokenizer;
/*
** Class derived from sqlit3_tokenizer_cursor
*/
typedef struct porter_tokenizer_cursor {
sqlite3_tokenizer_cursor base;
const char *zInput; /* input we are tokenizing */
int nInput; /* size of the input */
int iOffset; /* current position in zInput */
int iToken; /* index of next token to be returned */
char *zToken; /* storage for current token */
int nAllocated; /* space allocated to zToken buffer */
} porter_tokenizer_cursor;
/* Forward declaration */
static const sqlite3_tokenizer_module porterTokenizerModule;
/*
** Create a new tokenizer instance.
*/
static int porterCreate(
int argc, const char * const *argv,
sqlite3_tokenizer **ppTokenizer
){
porter_tokenizer *t;
t = (porter_tokenizer *) sqlite3_malloc(sizeof(*t));
if( t==NULL ) return SQLITE_NOMEM;
memset(t, 0, sizeof(*t));
*ppTokenizer = &t->base;
return SQLITE_OK;
}
/*
** Destroy a tokenizer
*/
static int porterDestroy(sqlite3_tokenizer *pTokenizer){
sqlite3_free(pTokenizer);
return SQLITE_OK;
}
/*
** Prepare to begin tokenizing a particular string. The input
** string to be tokenized is zInput[0..nInput-1]. A cursor
** used to incrementally tokenize this string is returned in
** *ppCursor.
*/
static int porterOpen(
sqlite3_tokenizer *pTokenizer, /* The tokenizer */
const char *zInput, int nInput, /* String to be tokenized */
sqlite3_tokenizer_cursor **ppCursor /* OUT: Tokenization cursor */
){
porter_tokenizer_cursor *c;
c = (porter_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
if( c==NULL ) return SQLITE_NOMEM;
c->zInput = zInput;
if( zInput==0 ){
c->nInput = 0;
}else if( nInput<0 ){
c->nInput = (int)strlen(zInput);
}else{
c->nInput = nInput;
}
c->iOffset = 0; /* start tokenizing at the beginning */
c->iToken = 0;
c->zToken = NULL; /* no space allocated, yet. */
c->nAllocated = 0;
*ppCursor = &c->base;
return SQLITE_OK;
}
/*
** Close a tokenization cursor previously opened by a call to
** porterOpen() above.
*/
static int porterClose(sqlite3_tokenizer_cursor *pCursor){
porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
sqlite3_free(c->zToken);
sqlite3_free(c);
return SQLITE_OK;
}
/*
** Vowel or consonant
*/
static const char cType[] = {
0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 0,
1, 1, 1, 2, 1
};
/*
** isConsonant() and isVowel() determine if their first character in
** the string they point to is a consonant or a vowel, according
** to Porter ruls.
**
** A consonate is any letter other than 'a', 'e', 'i', 'o', or 'u'.
** 'Y' is a consonant unless it follows another consonant,
** in which case it is a vowel.
**
** In these routine, the letters are in reverse order. So the 'y' rule
** is that 'y' is a consonant unless it is followed by another
** consonent.
*/
static int isVowel(const char*);
static int isConsonant(const char *z){
int j;
char x = *z;
if( x==0 ) return 0;
assert( x>='a' && x<='z' );
j = cType[x-'a'];
if( j<2 ) return j;
return z[1]==0 || isVowel(z + 1);
}
static int isVowel(const char *z){
int j;
char x = *z;
if( x==0 ) return 0;
assert( x>='a' && x<='z' );
j = cType[x-'a'];
if( j<2 ) return 1-j;
return isConsonant(z + 1);
}
/*
** Let any sequence of one or more vowels be represented by V and let
** C be sequence of one or more consonants. Then every word can be
** represented as:
**
** [C] (VC){m} [V]
**
** In prose: A word is an optional consonant followed by zero or
** vowel-consonant pairs followed by an optional vowel. "m" is the
** number of vowel consonant pairs. This routine computes the value
** of m for the first i bytes of a word.
**
** Return true if the m-value for z is 1 or more. In other words,
** return true if z contains at least one vowel that is followed
** by a consonant.
sqlite-amalgamation.c view on Meta::CPAN
}
break;
case 't':
stem(&z, "eta", "", m_gt_1) ||
stem(&z, "iti", "", m_gt_1);
break;
case 'u':
if( z[0]=='s' && z[2]=='o' && m_gt_1(z+3) ){
z += 3;
}
break;
case 'v':
case 'z':
if( z[0]=='e' && z[2]=='i' && m_gt_1(z+3) ){
z += 3;
}
break;
}
/* Step 5a */
if( z[0]=='e' ){
if( m_gt_1(z+1) ){
z++;
}else if( m_eq_1(z+1) && !star_oh(z+1) ){
z++;
}
}
/* Step 5b */
if( m_gt_1(z) && z[0]=='l' && z[1]=='l' ){
z++;
}
/* z[] is now the stemmed word in reverse order. Flip it back
** around into forward order and return.
*/
*pnOut = i = strlen(z);
zOut[i] = 0;
while( *z ){
zOut[--i] = *(z++);
}
}
/*
** Characters that can be part of a token. We assume any character
** whose value is greater than 0x80 (any UTF character) can be
** part of a token. In other words, delimiters all must have
** values of 0x7f or lower.
*/
static const char porterIdChar[] = {
/* x0 x1 x2 x3 x4 x5 x6 x7 x8 x9 xA xB xC xD xE xF */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, /* 3x */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 4x */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, /* 5x */
0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 6x */
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, /* 7x */
};
#define isDelim(C) (((ch=C)&0x80)==0 && (ch<0x30 || !porterIdChar[ch-0x30]))
/*
** Extract the next token from a tokenization cursor. The cursor must
** have been opened by a prior call to porterOpen().
*/
static int porterNext(
sqlite3_tokenizer_cursor *pCursor, /* Cursor returned by porterOpen */
const char **pzToken, /* OUT: *pzToken is the token text */
int *pnBytes, /* OUT: Number of bytes in token */
int *piStartOffset, /* OUT: Starting offset of token */
int *piEndOffset, /* OUT: Ending offset of token */
int *piPosition /* OUT: Position integer of token */
){
porter_tokenizer_cursor *c = (porter_tokenizer_cursor *) pCursor;
const char *z = c->zInput;
while( c->iOffset<c->nInput ){
int iStartOffset, ch;
/* Scan past delimiter characters */
while( c->iOffset<c->nInput && isDelim(z[c->iOffset]) ){
c->iOffset++;
}
/* Count non-delimiter characters. */
iStartOffset = c->iOffset;
while( c->iOffset<c->nInput && !isDelim(z[c->iOffset]) ){
c->iOffset++;
}
if( c->iOffset>iStartOffset ){
int n = c->iOffset-iStartOffset;
if( n>c->nAllocated ){
c->nAllocated = n+20;
c->zToken = sqlite3_realloc(c->zToken, c->nAllocated);
if( c->zToken==NULL ) return SQLITE_NOMEM;
}
porter_stemmer(&z[iStartOffset], n, c->zToken, pnBytes);
*pzToken = c->zToken;
*piStartOffset = iStartOffset;
*piEndOffset = c->iOffset;
*piPosition = c->iToken++;
return SQLITE_OK;
}
}
return SQLITE_DONE;
}
/*
** The set of routines that implement the porter-stemmer tokenizer
*/
static const sqlite3_tokenizer_module porterTokenizerModule = {
0,
porterCreate,
porterDestroy,
porterOpen,
porterClose,
porterNext,
};
/*
** Allocate a new porter tokenizer. Return a pointer to the new
** tokenizer in *ppModule
*/
SQLITE_PRIVATE void sqlite3Fts3PorterTokenizerModule(
sqlite3_tokenizer_module const**ppModule
){
*ppModule = &porterTokenizerModule;
}
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
/************** End of fts3_porter.c *****************************************/
/************** Begin file fts3_tokenizer.c **********************************/
sqlite-amalgamation.c view on Meta::CPAN
if( n!=sizeof(pPtr) ){
sqlite3_result_error(context, "argument type mismatch", -1);
return;
}
pPtr = *(void **)sqlite3_value_blob(argv[1]);
pOld = sqlite3Fts3HashInsert(pHash, (void *)zName, nName, pPtr);
if( pOld==pPtr ){
sqlite3_result_error(context, "out of memory", -1);
return;
}
}else{
pPtr = sqlite3Fts3HashFind(pHash, zName, nName);
if( !pPtr ){
char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
sqlite3_result_error(context, zErr, -1);
sqlite3_free(zErr);
return;
}
}
sqlite3_result_blob(context, (void *)&pPtr, sizeof(pPtr), SQLITE_TRANSIENT);
}
#ifdef SQLITE_TEST
/*
** Implementation of a special SQL scalar function for testing tokenizers
** designed to be used in concert with the Tcl testing framework. This
** function must be called with two arguments:
**
** SELECT <function-name>(<key-name>, <input-string>);
** SELECT <function-name>(<key-name>, <pointer>);
**
** where <function-name> is the name passed as the second argument
** to the sqlite3Fts3InitHashTable() function (e.g. 'fts3_tokenizer')
** concatenated with the string '_test' (e.g. 'fts3_tokenizer_test').
**
** The return value is a string that may be interpreted as a Tcl
** list. For each token in the <input-string>, three elements are
** added to the returned list. The first is the token position, the
** second is the token text (folded, stemmed, etc.) and the third is the
** substring of <input-string> associated with the token. For example,
** using the built-in "simple" tokenizer:
**
** SELECT fts_tokenizer_test('simple', 'I don't see how');
**
** will return the string:
**
** "{0 i I 1 dont don't 2 see see 3 how how}"
**
*/
static void testFunc(
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
fts3Hash *pHash;
sqlite3_tokenizer_module *p;
sqlite3_tokenizer *pTokenizer = 0;
sqlite3_tokenizer_cursor *pCsr = 0;
const char *zErr = 0;
const char *zName;
int nName;
const char *zInput;
int nInput;
const char *zArg = 0;
const char *zToken;
int nToken;
int iStart;
int iEnd;
int iPos;
Tcl_Obj *pRet;
assert( argc==2 || argc==3 );
nName = sqlite3_value_bytes(argv[0]);
zName = (const char *)sqlite3_value_text(argv[0]);
nInput = sqlite3_value_bytes(argv[argc-1]);
zInput = (const char *)sqlite3_value_text(argv[argc-1]);
if( argc==3 ){
zArg = (const char *)sqlite3_value_text(argv[1]);
}
pHash = (fts3Hash *)sqlite3_user_data(context);
p = (sqlite3_tokenizer_module *)sqlite3Fts3HashFind(pHash, zName, nName+1);
if( !p ){
char *zErr = sqlite3_mprintf("unknown tokenizer: %s", zName);
sqlite3_result_error(context, zErr, -1);
sqlite3_free(zErr);
return;
}
pRet = Tcl_NewObj();
Tcl_IncrRefCount(pRet);
if( SQLITE_OK!=p->xCreate(zArg ? 1 : 0, &zArg, &pTokenizer) ){
zErr = "error in xCreate()";
goto finish;
}
pTokenizer->pModule = p;
if( SQLITE_OK!=p->xOpen(pTokenizer, zInput, nInput, &pCsr) ){
zErr = "error in xOpen()";
goto finish;
}
pCsr->pTokenizer = pTokenizer;
while( SQLITE_OK==p->xNext(pCsr, &zToken, &nToken, &iStart, &iEnd, &iPos) ){
Tcl_ListObjAppendElement(0, pRet, Tcl_NewIntObj(iPos));
Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
zToken = &zInput[iStart];
nToken = iEnd-iStart;
Tcl_ListObjAppendElement(0, pRet, Tcl_NewStringObj(zToken, nToken));
}
sqlite-amalgamation.c view on Meta::CPAN
zTest = sqlite3_mprintf("%s_test", zName);
zTest2 = sqlite3_mprintf("%s_internal_test", zName);
if( !zTest || !zTest2 ){
rc = SQLITE_NOMEM;
}
#endif
if( rc!=SQLITE_OK
|| (rc = sqlite3_create_function(db, zName, 1, any, p, scalarFunc, 0, 0))
|| (rc = sqlite3_create_function(db, zName, 2, any, p, scalarFunc, 0, 0))
#ifdef SQLITE_TEST
|| (rc = sqlite3_create_function(db, zTest, 2, any, p, testFunc, 0, 0))
|| (rc = sqlite3_create_function(db, zTest, 3, any, p, testFunc, 0, 0))
|| (rc = sqlite3_create_function(db, zTest2, 0, any, pdb, intTestFunc, 0, 0))
#endif
);
sqlite3_free(zTest);
sqlite3_free(zTest2);
return rc;
}
#endif /* !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3) */
/************** End of fts3_tokenizer.c **************************************/
/************** Begin file fts3_tokenizer1.c *********************************/
/*
** 2006 Oct 10
**
** The author disclaims copyright to this source code. In place of
** a legal notice, here is a blessing:
**
** May you do good and not evil.
** May you find forgiveness for yourself and forgive others.
** May you share freely, never taking more than you give.
**
******************************************************************************
**
** Implementation of the "simple" full-text-search tokenizer.
*/
/*
** The code in this file is only compiled if:
**
** * The FTS3 module is being built as an extension
** (in which case SQLITE_CORE is not defined), or
**
** * The FTS3 module is being built into the core of
** SQLite (in which case SQLITE_ENABLE_FTS3 is defined).
*/
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_FTS3)
typedef struct simple_tokenizer {
sqlite3_tokenizer base;
char delim[128]; /* flag ASCII delimiters */
} simple_tokenizer;
typedef struct simple_tokenizer_cursor {
sqlite3_tokenizer_cursor base;
const char *pInput; /* input we are tokenizing */
int nBytes; /* size of the input */
int iOffset; /* current position in pInput */
int iToken; /* index of next token to be returned */
char *pToken; /* storage for current token */
int nTokenAllocated; /* space allocated to zToken buffer */
} simple_tokenizer_cursor;
/* Forward declaration */
static const sqlite3_tokenizer_module simpleTokenizerModule;
static int simpleDelim(simple_tokenizer *t, unsigned char c){
return c<0x80 && t->delim[c];
}
/*
** Create a new tokenizer instance.
*/
static int simpleCreate(
int argc, const char * const *argv,
sqlite3_tokenizer **ppTokenizer
){
simple_tokenizer *t;
t = (simple_tokenizer *) sqlite3_malloc(sizeof(*t));
if( t==NULL ) return SQLITE_NOMEM;
memset(t, 0, sizeof(*t));
/* TODO(shess) Delimiters need to remain the same from run to run,
** else we need to reindex. One solution would be a meta-table to
** track such information in the database, then we'd only want this
** information on the initial create.
*/
if( argc>1 ){
int i, n = strlen(argv[1]);
for(i=0; i<n; i++){
unsigned char ch = argv[1][i];
/* We explicitly don't support UTF-8 delimiters for now. */
if( ch>=0x80 ){
sqlite3_free(t);
return SQLITE_ERROR;
}
t->delim[ch] = 1;
}
} else {
/* Mark non-alphanumeric ASCII characters as delimiters */
int i;
for(i=1; i<0x80; i++){
t->delim[i] = !isalnum(i);
}
}
*ppTokenizer = &t->base;
return SQLITE_OK;
}
/*
** Destroy a tokenizer
*/
static int simpleDestroy(sqlite3_tokenizer *pTokenizer){
sqlite3_free(pTokenizer);
return SQLITE_OK;
}
/*
** Prepare to begin tokenizing a particular string. The input
** string to be tokenized is pInput[0..nBytes-1]. A cursor
** used to incrementally tokenize this string is returned in
** *ppCursor.
*/
static int simpleOpen(
sqlite3_tokenizer *pTokenizer, /* The tokenizer */
const char *pInput, int nBytes, /* String to be tokenized */
sqlite3_tokenizer_cursor **ppCursor /* OUT: Tokenization cursor */
){
simple_tokenizer_cursor *c;
c = (simple_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
if( c==NULL ) return SQLITE_NOMEM;
c->pInput = pInput;
if( pInput==0 ){
c->nBytes = 0;
}else if( nBytes<0 ){
c->nBytes = (int)strlen(pInput);
}else{
c->nBytes = nBytes;
}
c->iOffset = 0; /* start tokenizing at the beginning */
c->iToken = 0;
c->pToken = NULL; /* no space allocated, yet. */
c->nTokenAllocated = 0;
*ppCursor = &c->base;
return SQLITE_OK;
}
/*
** Close a tokenization cursor previously opened by a call to
** simpleOpen() above.
*/
static int simpleClose(sqlite3_tokenizer_cursor *pCursor){
simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
sqlite3_free(c->pToken);
sqlite3_free(c);
return SQLITE_OK;
}
/*
** Extract the next token from a tokenization cursor. The cursor must
** have been opened by a prior call to simpleOpen().
*/
static int simpleNext(
sqlite3_tokenizer_cursor *pCursor, /* Cursor returned by simpleOpen */
const char **ppToken, /* OUT: *ppToken is the token text */
int *pnBytes, /* OUT: Number of bytes in token */
int *piStartOffset, /* OUT: Starting offset of token */
int *piEndOffset, /* OUT: Ending offset of token */
int *piPosition /* OUT: Position integer of token */
){
simple_tokenizer_cursor *c = (simple_tokenizer_cursor *) pCursor;
simple_tokenizer *t = (simple_tokenizer *) pCursor->pTokenizer;
unsigned char *p = (unsigned char *)c->pInput;
while( c->iOffset<c->nBytes ){
int iStartOffset;
int isAscii = 0;
/* Scan past delimiter characters */
while( c->iOffset<c->nBytes && simpleDelim(t, p[c->iOffset]) ){
c->iOffset++;
}
iStartOffset = c->iOffset;
{
register unsigned char uv;
uv = p[c->iOffset];
if (uv <= 0x7F) {
/* US-ASCII: Use simpleDelim to tokenize */
while( c->iOffset<c->nBytes && (p[c->iOffset] <= 0x7F) && !simpleDelim(t, p[c->iOffset]) ) {
c->iOffset++;
}
isAscii = 1;
}
else {
/* Non-ASCII: Assume per-character tokenization */
c->iOffset += (
(uv <= 0xDF) ? 2 :
(uv <= 0xEF) ? 3 :
4
);
if (uv <= 0xE3 || uv >= 0xEA) {
/* XXX: This needs to be updated with a proper "is punctuation" check. */
continue;
}
}
}
if( c->iOffset>iStartOffset ){
int i, n = c->iOffset-iStartOffset;
if( n>c->nTokenAllocated ){
c->nTokenAllocated = n+20;
c->pToken = sqlite3_realloc(c->pToken, c->nTokenAllocated);
if( c->pToken==NULL ) return SQLITE_NOMEM;
}
if (!isAscii) {
/* Was not ASCII, don't bother running tolower() */
memcpy(c->pToken, p+iStartOffset, n);
}
else for(i=0; i<n; i++){
/* TODO(shess) This needs expansion to handle UTF-8
** case-insensitivity.
*/
unsigned char ch = p[iStartOffset+i];
c->pToken[i] = ch<0x80 ? tolower(ch) : ch;
}
*ppToken = c->pToken;
sqlite-amalgamation.c view on Meta::CPAN
/*
** An rtree virtual-table object.
*/
struct Rtree {
sqlite3_vtab base;
sqlite3 *db; /* Host database connection */
int iNodeSize; /* Size in bytes of each node in the node table */
int nDim; /* Number of dimensions */
int nBytesPerCell; /* Bytes consumed per cell */
int iDepth; /* Current depth of the r-tree structure */
char *zDb; /* Name of database containing r-tree table */
char *zName; /* Name of r-tree table */
RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */
int nBusy; /* Current number of users of this structure */
/* List of nodes removed during a CondenseTree operation. List is
** linked together via the pointer normally used for hash chains -
** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree
** headed by the node (leaf nodes have RtreeNode.iNode==0).
*/
RtreeNode *pDeleted;
int iReinsertHeight; /* Height of sub-trees Reinsert() has run on */
/* Statements to read/write/delete a record from xxx_node */
sqlite3_stmt *pReadNode;
sqlite3_stmt *pWriteNode;
sqlite3_stmt *pDeleteNode;
/* Statements to read/write/delete a record from xxx_rowid */
sqlite3_stmt *pReadRowid;
sqlite3_stmt *pWriteRowid;
sqlite3_stmt *pDeleteRowid;
/* Statements to read/write/delete a record from xxx_parent */
sqlite3_stmt *pReadParent;
sqlite3_stmt *pWriteParent;
sqlite3_stmt *pDeleteParent;
int eCoordType;
};
/* Possible values for eCoordType: */
#define RTREE_COORD_REAL32 0
#define RTREE_COORD_INT32 1
/*
** The minimum number of cells allowed for a node is a third of the
** maximum. In Gutman's notation:
**
** m = M/3
**
** If an R*-tree "Reinsert" operation is required, the same number of
** cells are removed from the overfull node and reinserted into the tree.
*/
#define RTREE_MINCELLS(p) ((((p)->iNodeSize-4)/(p)->nBytesPerCell)/3)
#define RTREE_REINSERT(p) RTREE_MINCELLS(p)
#define RTREE_MAXCELLS 51
/*
** An rtree cursor object.
*/
struct RtreeCursor {
sqlite3_vtab_cursor base;
RtreeNode *pNode; /* Node cursor is currently pointing at */
int iCell; /* Index of current cell in pNode */
int iStrategy; /* Copy of idxNum search parameter */
int nConstraint; /* Number of entries in aConstraint */
RtreeConstraint *aConstraint; /* Search constraints. */
};
union RtreeCoord {
float f;
int i;
};
/*
** The argument is an RtreeCoord. Return the value stored within the RtreeCoord
** formatted as a double. This macro assumes that local variable pRtree points
** to the Rtree structure associated with the RtreeCoord.
*/
#define DCOORD(coord) ( \
(pRtree->eCoordType==RTREE_COORD_REAL32) ? \
((double)coord.f) : \
((double)coord.i) \
)
/*
** A search constraint.
*/
struct RtreeConstraint {
int iCoord; /* Index of constrained coordinate */
int op; /* Constraining operation */
double rValue; /* Constraint value. */
};
/* Possible values for RtreeConstraint.op */
#define RTREE_EQ 0x41
#define RTREE_LE 0x42
#define RTREE_LT 0x43
#define RTREE_GE 0x44
#define RTREE_GT 0x45
/*
** An rtree structure node.
**
** Data format (RtreeNode.zData):
**
** 1. If the node is the root node (node 1), then the first 2 bytes
** of the node contain the tree depth as a big-endian integer.
** For non-root nodes, the first 2 bytes are left unused.
**
** 2. The next 2 bytes contain the number of entries currently
** stored in the node.
**
** 3. The remainder of the node contains the node entries. Each entry
** consists of a single 8-byte integer followed by an even number
** of 4-byte coordinates. For leaf nodes the integer is the rowid
** of a record. For internal nodes it is the node number of a
** child page.
*/
struct RtreeNode {
RtreeNode *pParent; /* Parent node */
i64 iNode;
int nRef;
sqlite-amalgamation.c view on Meta::CPAN
}
/*
** Decrement the r-tree reference count. When the reference count reaches
** zero the structure is deleted.
*/
static void rtreeRelease(Rtree *pRtree){
pRtree->nBusy--;
if( pRtree->nBusy==0 ){
sqlite3_finalize(pRtree->pReadNode);
sqlite3_finalize(pRtree->pWriteNode);
sqlite3_finalize(pRtree->pDeleteNode);
sqlite3_finalize(pRtree->pReadRowid);
sqlite3_finalize(pRtree->pWriteRowid);
sqlite3_finalize(pRtree->pDeleteRowid);
sqlite3_finalize(pRtree->pReadParent);
sqlite3_finalize(pRtree->pWriteParent);
sqlite3_finalize(pRtree->pDeleteParent);
sqlite3_free(pRtree);
}
}
/*
** Rtree virtual table module xDisconnect method.
*/
static int rtreeDisconnect(sqlite3_vtab *pVtab){
rtreeRelease((Rtree *)pVtab);
return SQLITE_OK;
}
/*
** Rtree virtual table module xDestroy method.
*/
static int rtreeDestroy(sqlite3_vtab *pVtab){
Rtree *pRtree = (Rtree *)pVtab;
int rc;
char *zCreate = sqlite3_mprintf(
"DROP TABLE '%q'.'%q_node';"
"DROP TABLE '%q'.'%q_rowid';"
"DROP TABLE '%q'.'%q_parent';",
pRtree->zDb, pRtree->zName,
pRtree->zDb, pRtree->zName,
pRtree->zDb, pRtree->zName
);
if( !zCreate ){
rc = SQLITE_NOMEM;
}else{
rc = sqlite3_exec(pRtree->db, zCreate, 0, 0, 0);
sqlite3_free(zCreate);
}
if( rc==SQLITE_OK ){
rtreeRelease(pRtree);
}
return rc;
}
/*
** Rtree virtual table module xOpen method.
*/
static int rtreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
int rc = SQLITE_NOMEM;
RtreeCursor *pCsr;
pCsr = (RtreeCursor *)sqlite3_malloc(sizeof(RtreeCursor));
if( pCsr ){
memset(pCsr, 0, sizeof(RtreeCursor));
pCsr->base.pVtab = pVTab;
rc = SQLITE_OK;
}
*ppCursor = (sqlite3_vtab_cursor *)pCsr;
return rc;
}
/*
** Rtree virtual table module xClose method.
*/
static int rtreeClose(sqlite3_vtab_cursor *cur){
Rtree *pRtree = (Rtree *)(cur->pVtab);
int rc;
RtreeCursor *pCsr = (RtreeCursor *)cur;
sqlite3_free(pCsr->aConstraint);
rc = nodeRelease(pRtree, pCsr->pNode);
sqlite3_free(pCsr);
return rc;
}
/*
** Rtree virtual table module xEof method.
**
** Return non-zero if the cursor does not currently point to a valid
** record (i.e if the scan has finished), or zero otherwise.
*/
static int rtreeEof(sqlite3_vtab_cursor *cur){
RtreeCursor *pCsr = (RtreeCursor *)cur;
return (pCsr->pNode==0);
}
/*
** Cursor pCursor currently points to a cell in a non-leaf page.
** Return true if the sub-tree headed by the cell is filtered
** (excluded) by the constraints in the pCursor->aConstraint[]
** array, or false otherwise.
*/
static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
RtreeCell cell;
int ii;
int bRes = 0;
nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
for(ii=0; bRes==0 && ii<pCursor->nConstraint; ii++){
RtreeConstraint *p = &pCursor->aConstraint[ii];
double cell_min = DCOORD(cell.aCoord[(p->iCoord>>1)*2]);
double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE
|| p->op==RTREE_GT || p->op==RTREE_EQ
);
switch( p->op ){
case RTREE_LE: case RTREE_LT: bRes = p->rValue<cell_min; break;
case RTREE_GE: case RTREE_GT: bRes = p->rValue>cell_max; break;
case RTREE_EQ:
bRes = (p->rValue>cell_max || p->rValue<cell_min);
break;
}
}
return bRes;
}
/*
** Return true if the cell that cursor pCursor currently points to
** would be filtered (excluded) by the constraints in the
** pCursor->aConstraint[] array, or false otherwise.
**
** This function assumes that the cell is part of a leaf node.
*/
static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
RtreeCell cell;
int ii;
nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
for(ii=0; ii<pCursor->nConstraint; ii++){
RtreeConstraint *p = &pCursor->aConstraint[ii];
double coord = DCOORD(cell.aCoord[p->iCoord]);
int res;
assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE
|| p->op==RTREE_GT || p->op==RTREE_EQ
);
switch( p->op ){
case RTREE_LE: res = (coord<=p->rValue); break;
case RTREE_LT: res = (coord<p->rValue); break;
case RTREE_GE: res = (coord>=p->rValue); break;
case RTREE_GT: res = (coord>p->rValue); break;
case RTREE_EQ: res = (coord==p->rValue); break;
}
if( !res ) return 1;
}
return 0;
}
/*
** Cursor pCursor currently points at a node that heads a sub-tree of
** height iHeight (if iHeight==0, then the node is a leaf). Descend
** to point to the left-most cell of the sub-tree that matches the
** configured constraints.
*/
static int descendToCell(
Rtree *pRtree,
RtreeCursor *pCursor,
int iHeight,
int *pEof /* OUT: Set to true if cannot descend */
){
int isEof;
int rc;
int ii;
RtreeNode *pChild;
sqlite3_int64 iRowid;
RtreeNode *pSavedNode = pCursor->pNode;
int iSavedCell = pCursor->iCell;
assert( iHeight>=0 );
if( iHeight==0 ){
isEof = testRtreeEntry(pRtree, pCursor);
}else{
isEof = testRtreeCell(pRtree, pCursor);
}
if( isEof || iHeight==0 ){
*pEof = isEof;
return SQLITE_OK;
}
iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
rc = nodeAcquire(pRtree, iRowid, pCursor->pNode, &pChild);
if( rc!=SQLITE_OK ){
return rc;
}
nodeRelease(pRtree, pCursor->pNode);
pCursor->pNode = pChild;
isEof = 1;
for(ii=0; isEof && ii<NCELL(pChild); ii++){
pCursor->iCell = ii;
rc = descendToCell(pRtree, pCursor, iHeight-1, &isEof);
if( rc!=SQLITE_OK ){
return rc;
}
}
if( isEof ){
assert( pCursor->pNode==pChild );
nodeReference(pSavedNode);
nodeRelease(pRtree, pChild);
pCursor->pNode = pSavedNode;
pCursor->iCell = iSavedCell;
}
*pEof = isEof;
return SQLITE_OK;
}
/*
** One of the cells in node pNode is guaranteed to have a 64-bit
** integer value equal to iRowid. Return the index of this cell.
*/
static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
int ii;
for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
assert( ii<(NCELL(pNode)-1) );
}
return ii;
}
/*
** Return the index of the cell containing a pointer to node pNode
** in its parent. If pNode is the root node, return -1.
*/
static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
RtreeNode *pParent = pNode->pParent;
if( pParent ){
return nodeRowidIndex(pRtree, pParent, pNode->iNode);
}
return -1;
}
/*
** Rtree virtual table module xNext method.
*/
static int rtreeNext(sqlite3_vtab_cursor *pVtabCursor){
Rtree *pRtree = (Rtree *)(pVtabCursor->pVtab);
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
int rc = SQLITE_OK;
if( pCsr->iStrategy==1 ){
/* This "scan" is a direct lookup by rowid. There is no next entry. */
nodeRelease(pRtree, pCsr->pNode);
pCsr->pNode = 0;
}
else if( pCsr->pNode ){
/* Move to the next entry that matches the configured constraints. */
int iHeight = 0;
while( pCsr->pNode ){
RtreeNode *pNode = pCsr->pNode;
int nCell = NCELL(pNode);
for(pCsr->iCell++; pCsr->iCell<nCell; pCsr->iCell++){
int isEof;
rc = descendToCell(pRtree, pCsr, iHeight, &isEof);
if( rc!=SQLITE_OK || !isEof ){
return rc;
}
}
pCsr->pNode = pNode->pParent;
pCsr->iCell = nodeParentIndex(pRtree, pNode);
nodeReference(pCsr->pNode);
nodeRelease(pRtree, pNode);
iHeight++;
}
}
return rc;
}
/*
** Rtree virtual table module xRowid method.
*/
static int rtreeRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *pRowid){
Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
assert(pCsr->pNode);
*pRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
return SQLITE_OK;
}
/*
** Rtree virtual table module xColumn method.
*/
static int rtreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
Rtree *pRtree = (Rtree *)cur->pVtab;
RtreeCursor *pCsr = (RtreeCursor *)cur;
if( i==0 ){
i64 iRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell);
sqlite3_result_int64(ctx, iRowid);
}else{
RtreeCoord c;
nodeGetCoord(pRtree, pCsr->pNode, pCsr->iCell, i-1, &c);
if( pRtree->eCoordType==RTREE_COORD_REAL32 ){
sqlite3_result_double(ctx, c.f);
}else{
assert( pRtree->eCoordType==RTREE_COORD_INT32 );
sqlite3_result_int(ctx, c.i);
}
}
return SQLITE_OK;
}
/*
** Use nodeAcquire() to obtain the leaf node containing the record with
** rowid iRowid. If successful, set *ppLeaf to point to the node and
** return SQLITE_OK. If there is no such record in the table, set
** *ppLeaf to 0 and return SQLITE_OK. If an error occurs, set *ppLeaf
** to zero and return an SQLite error code.
*/
static int findLeafNode(Rtree *pRtree, i64 iRowid, RtreeNode **ppLeaf){
int rc;
*ppLeaf = 0;
sqlite3_bind_int64(pRtree->pReadRowid, 1, iRowid);
if( sqlite3_step(pRtree->pReadRowid)==SQLITE_ROW ){
i64 iNode = sqlite3_column_int64(pRtree->pReadRowid, 0);
rc = nodeAcquire(pRtree, iNode, 0, ppLeaf);
sqlite3_reset(pRtree->pReadRowid);
}else{
rc = sqlite3_reset(pRtree->pReadRowid);
}
return rc;
}
/*
** Rtree virtual table module xFilter method.
*/
static int rtreeFilter(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
RtreeNode *pRoot = 0;
int ii;
int rc = SQLITE_OK;
rtreeReference(pRtree);
sqlite3_free(pCsr->aConstraint);
pCsr->aConstraint = 0;
pCsr->iStrategy = idxNum;
if( idxNum==1 ){
/* Special case - lookup by rowid. */
RtreeNode *pLeaf; /* Leaf on which the required cell resides */
i64 iRowid = sqlite3_value_int64(argv[0]);
rc = findLeafNode(pRtree, iRowid, &pLeaf);
pCsr->pNode = pLeaf;
if( pLeaf && rc==SQLITE_OK ){
pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
}
}else{
/* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array
** with the configured constraints.
*/
if( argc>0 ){
pCsr->aConstraint = sqlite3_malloc(sizeof(RtreeConstraint)*argc);
pCsr->nConstraint = argc;
if( !pCsr->aConstraint ){
rc = SQLITE_NOMEM;
}else{
assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
for(ii=0; ii<argc; ii++){
RtreeConstraint *p = &pCsr->aConstraint[ii];
p->op = idxStr[ii*2];
p->iCoord = idxStr[ii*2+1]-'a';
p->rValue = sqlite3_value_double(argv[ii]);
}
}
}
if( rc==SQLITE_OK ){
pCsr->pNode = 0;
rc = nodeAcquire(pRtree, 1, 0, &pRoot);
}
if( rc==SQLITE_OK ){
int isEof = 1;
int nCell = NCELL(pRoot);
pCsr->pNode = pRoot;
for(pCsr->iCell=0; rc==SQLITE_OK && pCsr->iCell<nCell; pCsr->iCell++){
assert( pCsr->pNode==pRoot );
rc = descendToCell(pRtree, pCsr, pRtree->iDepth, &isEof);
if( !isEof ){
break;
}
}
sqlite-amalgamation.c view on Meta::CPAN
if( sqlite3_value_type(azData[2])==SQLITE_NULL ){
rc = newRowid(pRtree, &cell.iRowid);
}else{
cell.iRowid = sqlite3_value_int64(azData[2]);
sqlite3_bind_int64(pRtree->pReadRowid, 1, cell.iRowid);
if( SQLITE_ROW==sqlite3_step(pRtree->pReadRowid) ){
sqlite3_reset(pRtree->pReadRowid);
rc = SQLITE_CONSTRAINT;
goto constraint;
}
rc = sqlite3_reset(pRtree->pReadRowid);
}
if( rc==SQLITE_OK ){
rc = ChooseLeaf(pRtree, &cell, 0, &pLeaf);
}
if( rc==SQLITE_OK ){
int rc2;
pRtree->iReinsertHeight = -1;
rc = rtreeInsertCell(pRtree, pLeaf, &cell, 0);
rc2 = nodeRelease(pRtree, pLeaf);
if( rc==SQLITE_OK ){
rc = rc2;
}
}
}
constraint:
rtreeRelease(pRtree);
return rc;
}
/*
** The xRename method for rtree module virtual tables.
*/
static int rtreeRename(sqlite3_vtab *pVtab, const char *zNewName){
Rtree *pRtree = (Rtree *)pVtab;
int rc = SQLITE_NOMEM;
char *zSql = sqlite3_mprintf(
"ALTER TABLE %Q.'%q_node' RENAME TO \"%w_node\";"
"ALTER TABLE %Q.'%q_parent' RENAME TO \"%w_parent\";"
"ALTER TABLE %Q.'%q_rowid' RENAME TO \"%w_rowid\";"
, pRtree->zDb, pRtree->zName, zNewName
, pRtree->zDb, pRtree->zName, zNewName
, pRtree->zDb, pRtree->zName, zNewName
);
if( zSql ){
rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0);
sqlite3_free(zSql);
}
return rc;
}
static sqlite3_module rtreeModule = {
0, /* iVersion */
rtreeCreate, /* xCreate - create a table */
rtreeConnect, /* xConnect - connect to an existing table */
rtreeBestIndex, /* xBestIndex - Determine search strategy */
rtreeDisconnect, /* xDisconnect - Disconnect from a table */
rtreeDestroy, /* xDestroy - Drop a table */
rtreeOpen, /* xOpen - open a cursor */
rtreeClose, /* xClose - close a cursor */
rtreeFilter, /* xFilter - configure scan constraints */
rtreeNext, /* xNext - advance a cursor */
rtreeEof, /* xEof */
rtreeColumn, /* xColumn - read data */
rtreeRowid, /* xRowid - read data */
rtreeUpdate, /* xUpdate - write data */
0, /* xBegin - begin transaction */
0, /* xSync - sync transaction */
0, /* xCommit - commit transaction */
0, /* xRollback - rollback transaction */
0, /* xFindFunction - function overloading */
rtreeRename /* xRename - rename the table */
};
static int rtreeSqlInit(
Rtree *pRtree,
sqlite3 *db,
const char *zDb,
const char *zPrefix,
int isCreate
){
int rc = SQLITE_OK;
#define N_STATEMENT 9
static const char *azSql[N_STATEMENT] = {
/* Read and write the xxx_node table */
"SELECT data FROM '%q'.'%q_node' WHERE nodeno = :1",
"INSERT OR REPLACE INTO '%q'.'%q_node' VALUES(:1, :2)",
"DELETE FROM '%q'.'%q_node' WHERE nodeno = :1",
/* Read and write the xxx_rowid table */
"SELECT nodeno FROM '%q'.'%q_rowid' WHERE rowid = :1",
"INSERT OR REPLACE INTO '%q'.'%q_rowid' VALUES(:1, :2)",
"DELETE FROM '%q'.'%q_rowid' WHERE rowid = :1",
/* Read and write the xxx_parent table */
"SELECT parentnode FROM '%q'.'%q_parent' WHERE nodeno = :1",
"INSERT OR REPLACE INTO '%q'.'%q_parent' VALUES(:1, :2)",
"DELETE FROM '%q'.'%q_parent' WHERE nodeno = :1"
};
sqlite3_stmt **appStmt[N_STATEMENT];
int i;
pRtree->db = db;
if( isCreate ){
char *zCreate = sqlite3_mprintf(
"CREATE TABLE \"%w\".\"%w_node\"(nodeno INTEGER PRIMARY KEY, data BLOB);"
"CREATE TABLE \"%w\".\"%w_rowid\"(rowid INTEGER PRIMARY KEY, nodeno INTEGER);"
"CREATE TABLE \"%w\".\"%w_parent\"(nodeno INTEGER PRIMARY KEY, parentnode INTEGER);"
"INSERT INTO '%q'.'%q_node' VALUES(1, zeroblob(%d))",
zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, pRtree->iNodeSize
);
if( !zCreate ){
return SQLITE_NOMEM;
}
rc = sqlite3_exec(db, zCreate, 0, 0, 0);
sqlite3_free(zCreate);
if( rc!=SQLITE_OK ){
return rc;
}
}
( run in 1.003 second using v1.01-cache-2.11-cpan-13bb782fe5a )