DBD-SQLcipher
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#endif
#ifdef SQLITE_USER_AUTHENTICATION
sqlite3_userauth auth; /* User authentication information */
#endif
};
/*
** A macro to discover the encoding of a database.
*/
#define SCHEMA_ENC(db) ((db)->aDb[0].pSchema->enc)
#define ENC(db) ((db)->enc)
/*
** Possible values for the sqlite3.flags.
*/
#define SQLITE_VdbeTrace 0x00000001 /* True to trace VDBE execution */
#define SQLITE_InternChanges 0x00000002 /* Uncommitted Hash table changes */
#define SQLITE_FullFSync 0x00000004 /* Use full fsync on the backend */
#define SQLITE_CkptFullFSync 0x00000008 /* Use full fsync for checkpoint */
#define SQLITE_CacheSpill 0x00000010 /* OK to spill pager cache */
#define SQLITE_FullColNames 0x00000020 /* Show full column names on SELECT */
#define SQLITE_ShortColNames 0x00000040 /* Show short columns names */
#define SQLITE_CountRows 0x00000080 /* Count rows changed by INSERT, */
/* DELETE, or UPDATE and return */
/* the count using a callback. */
#define SQLITE_NullCallback 0x00000100 /* Invoke the callback once if the */
/* result set is empty */
#define SQLITE_SqlTrace 0x00000200 /* Debug print SQL as it executes */
#define SQLITE_VdbeListing 0x00000400 /* Debug listings of VDBE programs */
#define SQLITE_WriteSchema 0x00000800 /* OK to update SQLITE_MASTER */
#define SQLITE_VdbeAddopTrace 0x00001000 /* Trace sqlite3VdbeAddOp() calls */
#define SQLITE_IgnoreChecks 0x00002000 /* Do not enforce check constraints */
#define SQLITE_ReadUncommitted 0x0004000 /* For shared-cache mode */
#define SQLITE_LegacyFileFmt 0x00008000 /* Create new databases in format 1 */
#define SQLITE_RecoveryMode 0x00010000 /* Ignore schema errors */
#define SQLITE_ReverseOrder 0x00020000 /* Reverse unordered SELECTs */
#define SQLITE_RecTriggers 0x00040000 /* Enable recursive triggers */
#define SQLITE_ForeignKeys 0x00080000 /* Enforce foreign key constraints */
#define SQLITE_AutoIndex 0x00100000 /* Enable automatic indexes */
#define SQLITE_PreferBuiltin 0x00200000 /* Preference to built-in funcs */
#define SQLITE_LoadExtension 0x00400000 /* Enable load_extension */
#define SQLITE_EnableTrigger 0x00800000 /* True to enable triggers */
#define SQLITE_DeferFKs 0x01000000 /* Defer all FK constraints */
#define SQLITE_QueryOnly 0x02000000 /* Disable database changes */
#define SQLITE_VdbeEQP 0x04000000 /* Debug EXPLAIN QUERY PLAN */
/*
** Bits of the sqlite3.dbOptFlags field that are used by the
** sqlite3_test_control(SQLITE_TESTCTRL_OPTIMIZATIONS,...) interface to
** selectively disable various optimizations.
*/
#define SQLITE_QueryFlattener 0x0001 /* Query flattening */
#define SQLITE_ColumnCache 0x0002 /* Column cache */
#define SQLITE_GroupByOrder 0x0004 /* GROUPBY cover of ORDERBY */
#define SQLITE_FactorOutConst 0x0008 /* Constant factoring */
/* not used 0x0010 // Was: SQLITE_IdxRealAsInt */
#define SQLITE_DistinctOpt 0x0020 /* DISTINCT using indexes */
#define SQLITE_CoverIdxScan 0x0040 /* Covering index scans */
#define SQLITE_OrderByIdxJoin 0x0080 /* ORDER BY of joins via index */
#define SQLITE_SubqCoroutine 0x0100 /* Evaluate subqueries as coroutines */
#define SQLITE_Transitive 0x0200 /* Transitive constraints */
#define SQLITE_OmitNoopJoin 0x0400 /* Omit unused tables in joins */
#define SQLITE_Stat34 0x0800 /* Use STAT3 or STAT4 data */
#define SQLITE_AllOpts 0xffff /* All optimizations */
/*
** Macros for testing whether or not optimizations are enabled or disabled.
*/
#ifndef SQLITE_OMIT_BUILTIN_TEST
#define OptimizationDisabled(db, mask) (((db)->dbOptFlags&(mask))!=0)
#define OptimizationEnabled(db, mask) (((db)->dbOptFlags&(mask))==0)
#else
#define OptimizationDisabled(db, mask) 0
#define OptimizationEnabled(db, mask) 1
#endif
/*
** Return true if it OK to factor constant expressions into the initialization
** code. The argument is a Parse object for the code generator.
*/
#define ConstFactorOk(P) ((P)->okConstFactor)
/*
** Possible values for the sqlite.magic field.
** The numbers are obtained at random and have no special meaning, other
** than being distinct from one another.
*/
#define SQLITE_MAGIC_OPEN 0xa029a697 /* Database is open */
#define SQLITE_MAGIC_CLOSED 0x9f3c2d33 /* Database is closed */
#define SQLITE_MAGIC_SICK 0x4b771290 /* Error and awaiting close */
#define SQLITE_MAGIC_BUSY 0xf03b7906 /* Database currently in use */
#define SQLITE_MAGIC_ERROR 0xb5357930 /* An SQLITE_MISUSE error occurred */
#define SQLITE_MAGIC_ZOMBIE 0x64cffc7f /* Close with last statement close */
/*
** Each SQL function is defined by an instance of the following
** structure. A pointer to this structure is stored in the sqlite.aFunc
** hash table. When multiple functions have the same name, the hash table
** points to a linked list of these structures.
*/
struct FuncDef {
i16 nArg; /* Number of arguments. -1 means unlimited */
u16 funcFlags; /* Some combination of SQLITE_FUNC_* */
void *pUserData; /* User data parameter */
FuncDef *pNext; /* Next function with same name */
void (*xFunc)(sqlite3_context*,int,sqlite3_value**); /* Regular function */
void (*xStep)(sqlite3_context*,int,sqlite3_value**); /* Aggregate step */
void (*xFinalize)(sqlite3_context*); /* Aggregate finalizer */
char *zName; /* SQL name of the function. */
FuncDef *pHash; /* Next with a different name but the same hash */
FuncDestructor *pDestructor; /* Reference counted destructor function */
};
/*
** This structure encapsulates a user-function destructor callback (as
** configured using create_function_v2()) and a reference counter. When
** create_function_v2() is called to create a function with a destructor,
** a single object of this type is allocated. FuncDestructor.nRef is set to
** the number of FuncDef objects created (either 1 or 3, depending on whether
** or not the specified encoding is SQLITE_ANY). The FuncDef.pDestructor
**
** This code uses unstructured "goto" statements and does not look clean.
** But that is not due to sloppy coding habits. The code is written this
** way for performance, to avoid having to run the interrupt and progress
** checks on every opcode. This helps sqlite3_step() to run about 1.5%
** faster according to "valgrind --tool=cachegrind" */
check_for_interrupt:
if( db->u1.isInterrupted ) goto abort_due_to_interrupt;
#ifndef SQLITE_OMIT_PROGRESS_CALLBACK
/* Call the progress callback if it is configured and the required number
** of VDBE ops have been executed (either since this invocation of
** sqlite3VdbeExec() or since last time the progress callback was called).
** If the progress callback returns non-zero, exit the virtual machine with
** a return code SQLITE_ABORT.
*/
if( db->xProgress!=0 && nVmStep>=nProgressLimit ){
assert( db->nProgressOps!=0 );
nProgressLimit = nVmStep + db->nProgressOps - (nVmStep%db->nProgressOps);
if( db->xProgress(db->pProgressArg) ){
rc = SQLITE_INTERRUPT;
goto vdbe_error_halt;
}
}
#endif
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 && pOp->p1<=(p->nMem-p->nCursor) );
pIn1 = &aMem[pOp->p1];
assert( VdbeMemDynamic(pIn1)==0 );
memAboutToChange(p, pIn1);
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. After
** the jump, register P1 becomes undefined.
*/
case OP_Return: { /* in1 */
pIn1 = &aMem[pOp->p1];
assert( pIn1->flags==MEM_Int );
pc = (int)pIn1->u.i;
pIn1->flags = MEM_Undefined;
break;
}
/* Opcode: InitCoroutine P1 P2 P3 * *
**
** Set up register P1 so that it will Yield to the coroutine
** located at address P3.
**
** If P2!=0 then the coroutine implementation immediately follows
** this opcode. So jump over the coroutine implementation to
** address P2.
**
** See also: EndCoroutine
*/
case OP_InitCoroutine: { /* jump */
assert( pOp->p1>0 && pOp->p1<=(p->nMem-p->nCursor) );
assert( pOp->p2>=0 && pOp->p2<p->nOp );
assert( pOp->p3>=0 && pOp->p3<p->nOp );
pOut = &aMem[pOp->p1];
assert( !VdbeMemDynamic(pOut) );
pOut->u.i = pOp->p3 - 1;
pOut->flags = MEM_Int;
if( pOp->p2 ) pc = pOp->p2 - 1;
break;
}
/* Opcode: EndCoroutine P1 * * * *
**
** The instruction at the address in register P1 is a Yield.
** Jump to the P2 parameter of that Yield.
** After the jump, register P1 becomes undefined.
**
** See also: InitCoroutine
*/
case OP_EndCoroutine: { /* in1 */
VdbeOp *pCaller;
pIn1 = &aMem[pOp->p1];
assert( pIn1->flags==MEM_Int );
assert( pIn1->u.i>=0 && pIn1->u.i<p->nOp );
pCaller = &aOp[pIn1->u.i];
assert( pCaller->opcode==OP_Yield );
assert( pCaller->p2>=0 && pCaller->p2<p->nOp );
pc = pCaller->p2 - 1;
pIn1->flags = MEM_Undefined;
break;
}
/* Opcode: Yield P1 P2 * * *
**
** Swap the program counter with the value in register P1. This
** has the effect of yielding to a coroutine.
**
** If the coroutine that is launched by this instruction ends with
** Yield or Return then continue to the next instruction. But if
** the coroutine launched by this instruction ends with
** EndCoroutine, then jump to P2 rather than continuing with the
** next instruction.
**
** See also: InitCoroutine
*/
case OP_Yield: { /* in1, jump */
int pcDest;
pIn1 = &aMem[pOp->p1];
assert( VdbeMemDynamic(pIn1)==0 );
pIn1->flags = MEM_Int;
pcDest = (int)pIn1->u.i;
pIn1->u.i = pc;
REGISTER_TRACE(pOp->p1, pIn1);
pc = pcDest;
break;
}
/* Opcode: HaltIfNull P1 P2 P3 P4 P5
** Synopsis: if r[P3]=null halt
**
** Check the value in register P3. If it is NULL then Halt using
** parameter P1, P2, and P4 as if this were a Halt instruction. If the
** value in register P3 is not NULL, then this routine is a no-op.
** The P5 parameter should be 1.
*/
case OP_HaltIfNull: { /* in3 */
pIn3 = &aMem[pOp->p3];
if( (pIn3->flags & MEM_Null)==0 ) break;
/* Fall through into OP_Halt */
}
/* Opcode: Halt P1 P2 * P4 P5
**
** Exit immediately. All open cursors, 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.
**
** P5 is a value between 0 and 4, inclusive, that modifies the P4 string.
**
** 0: (no change)
** 1: NOT NULL contraint failed: P4
** 2: UNIQUE constraint failed: P4
** 3: CHECK constraint failed: P4
** 4: FOREIGN KEY constraint failed: P4
**
** If P5 is not zero and P4 is NULL, then everything after the ":" is
** omitted.
**
** 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.
** This routine is called 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
** insert 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
** put VALUES clause expressions into registers
** 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:
**
** 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
** end-coroutine X
** B: open write cursor to <table> and its indices
** C: yield X, at 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 an intermediate table to store the results of
** the select. The template is like this:
**
** 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
** end co-routine R
** B: open temp table
** L: yield X, at 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 */
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 iDataCur = 0; /* VDBE cursor that is the main data repository */
int iIdxCur = 0; /* First index cursor */
int ipkColumn = -1; /* Column that is the INTEGER PRIMARY KEY */
int endOfLoop; /* Label for the end of the insertion loop */
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 */
SelectDest dest; /* Destination for SELECT on rhs of INSERT */
int iDb; /* Index of database holding TABLE */
Db *pDb; /* The database containing table being inserted into */
u8 useTempTable = 0; /* Store SELECT results in intermediate table */
u8 appendFlag = 0; /* True if the insert is likely to be an append */
if( j==pTab->iPKey ){
ipkColumn = i; assert( !withoutRowid );
}
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pColumn->a[i].zName) && !withoutRowid ){
ipkColumn = i;
bIdListInOrder = 0;
}else{
sqlite3ErrorMsg(pParse, "table %S has no column named %s",
pTabList, 0, pColumn->a[i].zName);
pParse->checkSchema = 1;
goto insert_cleanup;
}
}
}
}
/* Figure out how many columns of data are supplied. If the data
** is coming from a SELECT statement, then generate a co-routine that
** produces a single row of the SELECT on each invocation. The
** co-routine is the common header to the 3rd and 4th templates.
*/
if( pSelect ){
/* Data is coming from a SELECT. Generate a co-routine to run the SELECT */
int regYield; /* Register holding co-routine entry-point */
int addrTop; /* Top of the co-routine */
int rc; /* Result code */
regYield = ++pParse->nMem;
addrTop = sqlite3VdbeCurrentAddr(v) + 1;
sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield, 0, addrTop);
sqlite3SelectDestInit(&dest, SRT_Coroutine, regYield);
dest.iSdst = bIdListInOrder ? regData : 0;
dest.nSdst = pTab->nCol;
rc = sqlite3Select(pParse, pSelect, &dest);
regFromSelect = dest.iSdst;
assert( pParse->nErr==0 || rc );
if( rc || db->mallocFailed ) goto insert_cleanup;
sqlite3VdbeAddOp1(v, OP_EndCoroutine, regYield);
sqlite3VdbeJumpHere(v, addrTop - 1); /* label B: */
assert( pSelect->pEList );
nColumn = pSelect->pEList->nExpr;
/* Set useTempTable to TRUE if the result of the SELECT statement
** should be written into a temporary table (template 4). Set to
** FALSE if each output row of the SELECT can be written directly into
** the destination table (template 3).
**
** A temp table must be used if the table being updated is also one
** of the tables being read by the SELECT statement. Also use a
** temp table in the case of row triggers.
*/
if( pTrigger || readsTable(pParse, iDb, pTab) ){
useTempTable = 1;
}
if( useTempTable ){
/* Invoke the coroutine to extract information from the SELECT
** and add it to a transient table srcTab. The code generated
** here is from the 4th template:
**
** B: open temp table
** L: yield X, goto M at EOF
** insert row from R..R+n into temp table
** goto L
** M: ...
*/
int regRec; /* Register to hold packed record */
int regTempRowid; /* Register to hold temp table ROWID */
int addrL; /* Label "L" */
srcTab = pParse->nTab++;
regRec = sqlite3GetTempReg(pParse);
regTempRowid = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn);
addrL = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec);
sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid);
sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrL);
sqlite3VdbeJumpHere(v, addrL);
sqlite3ReleaseTempReg(pParse, regRec);
sqlite3ReleaseTempReg(pParse, regTempRowid);
}
}else{
/* This is the case if the data for the INSERT is coming from a VALUES
** clause
*/
NameContext sNC;
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
srcTab = -1;
assert( useTempTable==0 );
nColumn = pList ? pList->nExpr : 0;
for(i=0; i<nColumn; i++){
if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){
goto insert_cleanup;
}
}
}
/* If there is no IDLIST term but the table has an integer primary
** key, the set the ipkColumn variable to the integer primary key
** column index in the original table definition.
*/
if( pColumn==0 && nColumn>0 ){
ipkColumn = pTab->iPKey;
}
/* Make sure the number of columns in the source data matches the number
** of columns to be inserted into the table.
*/
if( IsVirtual(pTab) ){
for(i=0; i<pTab->nCol; i++){
nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0);
}
}
if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){
explainComposite(pParse, p->op, iSub1, iSub2, p->op!=TK_ALL);
/* Compute collating sequences used by
** temporary tables needed to implement the compound select.
** Attach the KeyInfo structure to all temporary tables.
**
** This section is run by the right-most SELECT statement only.
** SELECT statements to the left always skip this part. The right-most
** SELECT might also skip this part if it has no ORDER BY clause and
** no temp tables are required.
*/
if( p->selFlags & SF_UsesEphemeral ){
int i; /* Loop counter */
KeyInfo *pKeyInfo; /* Collating sequence for the result set */
Select *pLoop; /* For looping through SELECT statements */
CollSeq **apColl; /* For looping through pKeyInfo->aColl[] */
int nCol; /* Number of columns in result set */
assert( p->pNext==0 );
nCol = p->pEList->nExpr;
pKeyInfo = sqlite3KeyInfoAlloc(db, nCol, 1);
if( !pKeyInfo ){
rc = SQLITE_NOMEM;
goto multi_select_end;
}
for(i=0, apColl=pKeyInfo->aColl; i<nCol; i++, apColl++){
*apColl = multiSelectCollSeq(pParse, p, i);
if( 0==*apColl ){
*apColl = db->pDfltColl;
}
}
for(pLoop=p; pLoop; pLoop=pLoop->pPrior){
for(i=0; i<2; i++){
int addr = pLoop->addrOpenEphm[i];
if( addr<0 ){
/* If [0] is unused then [1] is also unused. So we can
** always safely abort as soon as the first unused slot is found */
assert( pLoop->addrOpenEphm[1]<0 );
break;
}
sqlite3VdbeChangeP2(v, addr, nCol);
sqlite3VdbeChangeP4(v, addr, (char*)sqlite3KeyInfoRef(pKeyInfo),
P4_KEYINFO);
pLoop->addrOpenEphm[i] = -1;
}
}
sqlite3KeyInfoUnref(pKeyInfo);
}
multi_select_end:
pDest->iSdst = dest.iSdst;
pDest->nSdst = dest.nSdst;
sqlite3SelectDelete(db, pDelete);
return rc;
}
#endif /* SQLITE_OMIT_COMPOUND_SELECT */
/*
** Code an output subroutine for a coroutine implementation of a
** SELECT statment.
**
** The data to be output is contained in pIn->iSdst. There are
** pIn->nSdst columns to be output. pDest is where the output should
** be sent.
**
** regReturn is the number of the register holding the subroutine
** return address.
**
** If regPrev>0 then it is the first register in a vector that
** records the previous output. mem[regPrev] is a flag that is false
** if there has been no previous output. If regPrev>0 then code is
** generated to suppress duplicates. pKeyInfo is used for comparing
** keys.
**
** If the LIMIT found in p->iLimit is reached, jump immediately to
** iBreak.
*/
static int generateOutputSubroutine(
Parse *pParse, /* Parsing context */
Select *p, /* The SELECT statement */
SelectDest *pIn, /* Coroutine supplying data */
SelectDest *pDest, /* Where to send the data */
int regReturn, /* The return address register */
int regPrev, /* Previous result register. No uniqueness if 0 */
KeyInfo *pKeyInfo, /* For comparing with previous entry */
int iBreak /* Jump here if we hit the LIMIT */
){
Vdbe *v = pParse->pVdbe;
int iContinue;
int addr;
addr = sqlite3VdbeCurrentAddr(v);
iContinue = sqlite3VdbeMakeLabel(v);
/* Suppress duplicates for UNION, EXCEPT, and INTERSECT
*/
if( regPrev ){
int j1, j2;
j1 = sqlite3VdbeAddOp1(v, OP_IfNot, regPrev); VdbeCoverage(v);
j2 = sqlite3VdbeAddOp4(v, OP_Compare, pIn->iSdst, regPrev+1, pIn->nSdst,
(char*)sqlite3KeyInfoRef(pKeyInfo), P4_KEYINFO);
sqlite3VdbeAddOp3(v, OP_Jump, j2+2, iContinue, j2+2); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, j1);
sqlite3VdbeAddOp3(v, OP_Copy, pIn->iSdst, regPrev+1, pIn->nSdst-1);
sqlite3VdbeAddOp2(v, OP_Integer, 1, regPrev);
}
if( pParse->db->mallocFailed ) return 0;
/* Suppress the first OFFSET entries if there is an OFFSET clause
*/
codeOffset(v, p->iOffset, iContinue);
switch( pDest->eDest ){
/* Store the result as data using a unique key.
*/
case SRT_Table:
case SRT_EphemTab: {
int r1 = sqlite3GetTempReg(pParse);
int r2 = sqlite3GetTempReg(pParse);
sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSDParm, 1);
/* The LIMIT clause will jump out of the loop for us */
break;
}
#endif /* #ifndef SQLITE_OMIT_SUBQUERY */
/* The results are stored in a sequence of registers
** starting at pDest->iSdst. Then the co-routine yields.
*/
case SRT_Coroutine: {
if( pDest->iSdst==0 ){
pDest->iSdst = sqlite3GetTempRange(pParse, pIn->nSdst);
pDest->nSdst = pIn->nSdst;
}
sqlite3ExprCodeMove(pParse, pIn->iSdst, pDest->iSdst, pDest->nSdst);
sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
break;
}
/* If none of the above, then the result destination must be
** SRT_Output. This routine is never called with any other
** destination other than the ones handled above or SRT_Output.
**
** For SRT_Output, results are stored in a sequence of registers.
** Then the OP_ResultRow opcode is used to cause sqlite3_step() to
** return the next row of result.
*/
default: {
assert( pDest->eDest==SRT_Output );
sqlite3VdbeAddOp2(v, OP_ResultRow, pIn->iSdst, pIn->nSdst);
sqlite3ExprCacheAffinityChange(pParse, pIn->iSdst, pIn->nSdst);
break;
}
}
/* Jump to the end of the loop if the LIMIT is reached.
*/
if( p->iLimit ){
sqlite3VdbeAddOp3(v, OP_IfZero, p->iLimit, iBreak, -1); VdbeCoverage(v);
}
/* Generate the subroutine return
*/
sqlite3VdbeResolveLabel(v, iContinue);
sqlite3VdbeAddOp1(v, OP_Return, regReturn);
return addr;
}
/*
** Alternative compound select code generator for cases when there
** is an ORDER BY clause.
**
** We assume a query of the following form:
**
** <selectA> <operator> <selectB> ORDER BY <orderbylist>
**
** <operator> is one of UNION ALL, UNION, EXCEPT, or INTERSECT. The idea
** is to code both <selectA> and <selectB> with the ORDER BY clause as
** co-routines. Then run the co-routines in parallel and merge the results
** into the output. In addition to the two coroutines (called selectA and
** selectB) there are 7 subroutines:
**
** outA: Move the output of the selectA coroutine into the output
** of the compound query.
**
** outB: Move the output of the selectB coroutine into the output
** of the compound query. (Only generated for UNION and
** UNION ALL. EXCEPT and INSERTSECT never output a row that
** appears only in B.)
**
** AltB: Called when there is data from both coroutines and A<B.
**
** AeqB: Called when there is data from both coroutines and A==B.
**
** AgtB: Called when there is data from both coroutines and A>B.
**
** EofA: Called when data is exhausted from selectA.
**
** EofB: Called when data is exhausted from selectB.
**
** The implementation of the latter five subroutines depend on which
** <operator> is used:
**
**
** UNION ALL UNION EXCEPT INTERSECT
** ------------- ----------------- -------------- -----------------
** AltB: outA, nextA outA, nextA outA, nextA nextA
**
** AeqB: outA, nextA nextA nextA outA, nextA
**
** AgtB: outB, nextB outB, nextB nextB nextB
**
** EofA: outB, nextB outB, nextB halt halt
**
** EofB: outA, nextA outA, nextA outA, nextA halt
**
** In the AltB, AeqB, and AgtB subroutines, an EOF on A following nextA
** causes an immediate jump to EofA and an EOF on B following nextB causes
** an immediate jump to EofB. Within EofA and EofB, and EOF on entry or
** following nextX causes a jump to the end of the select processing.
**
** Duplicate removal in the UNION, EXCEPT, and INTERSECT cases is handled
** within the output subroutine. The regPrev register set holds the previously
** output value. A comparison is made against this value and the output
** is skipped if the next results would be the same as the previous.
**
** The implementation plan is to implement the two coroutines and seven
** subroutines first, then put the control logic at the bottom. Like this:
**
** goto Init
** coA: coroutine for left query (A)
** coB: coroutine for right query (B)
** outA: output one row of A
** outB: output one row of B (UNION and UNION ALL only)
** EofA: ...
** EofB: ...
** AltB: ...
** AeqB: ...
** AgtB: ...
** Init: initialize coroutine registers
** yield coA
** if eof(A) goto EofA
** yield coB
** if eof(B) goto EofB
** Cmpr: Compare A, B
** Jump AltB, AeqB, AgtB
** End: ...
**
** We call AltB, AeqB, AgtB, EofA, and EofB "subroutines" but they are not
** actually called using Gosub and they do not Return. EofA and EofB loop
** until all data is exhausted then jump to the "end" labe. AltB, AeqB,
** and AgtB jump to either L2 or to one of EofA or EofB.
*/
#ifndef SQLITE_OMIT_COMPOUND_SELECT
static int multiSelectOrderBy(
Parse *pParse, /* Parsing context */
Select *p, /* The right-most of SELECTs to be coded */
SelectDest *pDest /* What to do with query results */
){
int i, j; /* Loop counters */
Select *pPrior; /* Another SELECT immediately to our left */
Vdbe *v; /* Generate code to this VDBE */
SelectDest destA; /* Destination for coroutine A */
SelectDest destB; /* Destination for coroutine B */
int regAddrA; /* Address register for select-A coroutine */
int regAddrB; /* Address register for select-B coroutine */
int addrSelectA; /* Address of the select-A coroutine */
int addrSelectB; /* Address of the select-B coroutine */
int regOutA; /* Address register for the output-A subroutine */
int regOutB; /* Address register for the output-B subroutine */
int addrOutA; /* Address of the output-A subroutine */
int addrOutB = 0; /* Address of the output-B subroutine */
int addrEofA; /* Address of the select-A-exhausted subroutine */
int addrEofA_noB; /* Alternate addrEofA if B is uninitialized */
int addrEofB; /* Address of the select-B-exhausted subroutine */
int addrAltB; /* Address of the A<B subroutine */
int addrAeqB; /* Address of the A==B subroutine */
int addrAgtB; /* Address of the A>B subroutine */
int regLimitA; /* Limit register for select-A */
int regLimitB; /* Limit register for select-A */
int regPrev; /* A range of registers to hold previous output */
int savedLimit; /* Saved value of p->iLimit */
int savedOffset; /* Saved value of p->iOffset */
int labelCmpr; /* Label for the start of the merge algorithm */
int labelEnd; /* Label for the end of the overall SELECT stmt */
int j1; /* Jump instructions that get retargetted */
int op; /* One of TK_ALL, TK_UNION, TK_EXCEPT, TK_INTERSECT */
KeyInfo *pKeyDup = 0; /* Comparison information for duplicate removal */
KeyInfo *pKeyMerge; /* Comparison information for merging rows */
sqlite3 *db; /* Database connection */
ExprList *pOrderBy; /* The ORDER BY clause */
int nOrderBy; /* Number of terms in the ORDER BY clause */
int *aPermute; /* Mapping from ORDER BY terms to result set columns */
#ifndef SQLITE_OMIT_EXPLAIN
int iSub1; /* EQP id of left-hand query */
int iSub2; /* EQP id of right-hand query */
#endif
assert( p->pOrderBy!=0 );
assert( pKeyDup==0 ); /* "Managed" code needs this. Ticket #3382. */
db = pParse->db;
v = pParse->pVdbe;
assert( v!=0 ); /* Already thrown the error if VDBE alloc failed */
labelEnd = sqlite3VdbeMakeLabel(v);
labelCmpr = sqlite3VdbeMakeLabel(v);
/* Patch up the ORDER BY clause
*/
op = p->op;
pPrior = p->pPrior;
assert( pPrior->pOrderBy==0 );
pOrderBy = p->pOrderBy;
assert( pOrderBy );
nOrderBy = pOrderBy->nExpr;
/* For operators other than UNION ALL we have to make sure that
** the ORDER BY clause covers every term of the result set. Add
** terms to the ORDER BY clause as necessary.
*/
if( op!=TK_ALL ){
for(i=1; db->mallocFailed==0 && i<=p->pEList->nExpr; i++){
struct ExprList_item *pItem;
for(j=0, pItem=pOrderBy->a; j<nOrderBy; j++, pItem++){
assert( pItem->u.x.iOrderByCol>0 );
if( pItem->u.x.iOrderByCol==i ) break;
}
if( j==nOrderBy ){
/* Reattach the ORDER BY clause to the query.
*/
p->pOrderBy = pOrderBy;
pPrior->pOrderBy = sqlite3ExprListDup(pParse->db, pOrderBy, 0);
/* Allocate a range of temporary registers and the KeyInfo needed
** for the logic that removes duplicate result rows when the
** operator is UNION, EXCEPT, or INTERSECT (but not UNION ALL).
*/
if( op==TK_ALL ){
regPrev = 0;
}else{
int nExpr = p->pEList->nExpr;
assert( nOrderBy>=nExpr || db->mallocFailed );
regPrev = pParse->nMem+1;
pParse->nMem += nExpr+1;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regPrev);
pKeyDup = sqlite3KeyInfoAlloc(db, nExpr, 1);
if( pKeyDup ){
assert( sqlite3KeyInfoIsWriteable(pKeyDup) );
for(i=0; i<nExpr; i++){
pKeyDup->aColl[i] = multiSelectCollSeq(pParse, p, i);
pKeyDup->aSortOrder[i] = 0;
}
}
}
/* Separate the left and the right query from one another
*/
p->pPrior = 0;
pPrior->pNext = 0;
sqlite3ResolveOrderGroupBy(pParse, p, p->pOrderBy, "ORDER");
if( pPrior->pPrior==0 ){
sqlite3ResolveOrderGroupBy(pParse, pPrior, pPrior->pOrderBy, "ORDER");
}
/* Compute the limit registers */
computeLimitRegisters(pParse, p, labelEnd);
if( p->iLimit && op==TK_ALL ){
regLimitA = ++pParse->nMem;
regLimitB = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Copy, p->iOffset ? p->iOffset+1 : p->iLimit,
regLimitA);
sqlite3VdbeAddOp2(v, OP_Copy, regLimitA, regLimitB);
}else{
regLimitA = regLimitB = 0;
}
sqlite3ExprDelete(db, p->pLimit);
p->pLimit = 0;
sqlite3ExprDelete(db, p->pOffset);
p->pOffset = 0;
regAddrA = ++pParse->nMem;
regAddrB = ++pParse->nMem;
regOutA = ++pParse->nMem;
regOutB = ++pParse->nMem;
sqlite3SelectDestInit(&destA, SRT_Coroutine, regAddrA);
sqlite3SelectDestInit(&destB, SRT_Coroutine, regAddrB);
/* Generate a coroutine to evaluate the SELECT statement to the
** left of the compound operator - the "A" select.
*/
addrSelectA = sqlite3VdbeCurrentAddr(v) + 1;
j1 = sqlite3VdbeAddOp3(v, OP_InitCoroutine, regAddrA, 0, addrSelectA);
VdbeComment((v, "left SELECT"));
pPrior->iLimit = regLimitA;
explainSetInteger(iSub1, pParse->iNextSelectId);
sqlite3Select(pParse, pPrior, &destA);
sqlite3VdbeAddOp1(v, OP_EndCoroutine, regAddrA);
sqlite3VdbeJumpHere(v, j1);
/* Generate a coroutine to evaluate the SELECT statement on
** the right - the "B" select
*/
addrSelectB = sqlite3VdbeCurrentAddr(v) + 1;
j1 = sqlite3VdbeAddOp3(v, OP_InitCoroutine, regAddrB, 0, addrSelectB);
VdbeComment((v, "right SELECT"));
savedLimit = p->iLimit;
savedOffset = p->iOffset;
p->iLimit = regLimitB;
p->iOffset = 0;
explainSetInteger(iSub2, pParse->iNextSelectId);
sqlite3Select(pParse, p, &destB);
p->iLimit = savedLimit;
p->iOffset = savedOffset;
sqlite3VdbeAddOp1(v, OP_EndCoroutine, regAddrB);
/* Generate a subroutine that outputs the current row of the A
** select as the next output row of the compound select.
*/
VdbeNoopComment((v, "Output routine for A"));
addrOutA = generateOutputSubroutine(pParse,
p, &destA, pDest, regOutA,
regPrev, pKeyDup, labelEnd);
/* Generate a subroutine that outputs the current row of the B
** select as the next output row of the compound select.
*/
if( op==TK_ALL || op==TK_UNION ){
VdbeNoopComment((v, "Output routine for B"));
addrOutB = generateOutputSubroutine(pParse,
p, &destB, pDest, regOutB,
regPrev, pKeyDup, labelEnd);
}
sqlite3KeyInfoUnref(pKeyDup);
/* Generate a subroutine to run when the results from select A
** are exhausted and only data in select B remains.
*/
if( op==TK_EXCEPT || op==TK_INTERSECT ){
addrEofA_noB = addrEofA = labelEnd;
}else{
VdbeNoopComment((v, "eof-A subroutine"));
addrEofA = sqlite3VdbeAddOp2(v, OP_Gosub, regOutB, addrOutB);
addrEofA_noB = sqlite3VdbeAddOp2(v, OP_Yield, regAddrB, labelEnd);
VdbeCoverage(v);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofA);
p->nSelectRow += pPrior->nSelectRow;
}
/* Generate a subroutine to run when the results from select B
** are exhausted and only data in select A remains.
*/
if( op==TK_INTERSECT ){
addrEofB = addrEofA;
if( p->nSelectRow > pPrior->nSelectRow ) p->nSelectRow = pPrior->nSelectRow;
}else{
VdbeNoopComment((v, "eof-B subroutine"));
addrEofB = sqlite3VdbeAddOp2(v, OP_Gosub, regOutA, addrOutA);
sqlite3VdbeAddOp2(v, OP_Yield, regAddrA, labelEnd); VdbeCoverage(v);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addrEofB);
}
( run in 2.282 seconds using v1.01-cache-2.11-cpan-13bb782fe5a )