DBD-SQLite
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dbdimp_tokenizer.inc view on Meta::CPAN
typedef struct perl_tokenizer {
sqlite3_tokenizer base;
SV *coderef; /* the perl tokenizer is a coderef that takes
a string and returns a cursor coderef */
} perl_tokenizer;
typedef struct perl_tokenizer_cursor {
sqlite3_tokenizer_cursor base;
SV *coderef; /* ref to the closure that returns terms */
char *pToken; /* storage for a copy of the last token */
int nTokenAllocated; /* space allocated to pToken buffer */
/* members below are only used if the input string is in utf8 */
const char *pInput; /* input we are tokenizing */
const char *currentByte; /* pointer into pInput */
int currentChar; /* char position corresponding to currentByte */
} perl_tokenizer_cursor;
/*
** Create a new tokenizer instance.
** Will be called whenever a FTS3 table is created with
** CREATE .. USING fts3( ... , tokenize=perl qualified::function::name)
** where qualified::function::name is a fully qualified perl function
*/
static int perl_tokenizer_Create(
int argc, const char * const *argv,
sqlite3_tokenizer **ppTokenizer
dbdimp_tokenizer.inc view on Meta::CPAN
sv_free(t->coderef);
sqlite3_free(t);
return SQLITE_OK;
}
/*
** Prepare to begin tokenizing a particular string. The input
** string to be tokenized is supposed to be pInput[0..nBytes-1] ..
** except that nBytes passed by fts3 is -1 (don't know why) !
** This is passed to the tokenizer instance, which then returns a
** closure implementing the cursor (so the cursor is again a coderef).
*/
static int perl_tokenizer_Open(
sqlite3_tokenizer *pTokenizer, /* Tokenizer object */
const char *pInput, int nBytes, /* Input buffer */
sqlite3_tokenizer_cursor **ppCursor /* OUT: Created tokenizer cursor */
){
dTHX;
dSP;
dMY_CXT;
U32 flags;
SV *perl_string;
int n_retval;
/* build a Perl copy of the input string */
if (nBytes < 0) { /* we get -1 from fts3. Don't know why ! */
dbdimp_tokenizer.inc view on Meta::CPAN
break;
default:
break;
}
DBD_SQLITE_UTF8_DECODE_IF_NEEDED(perl_string, MY_CXT.last_dbh_string_mode);
perl_tokenizer *t = (perl_tokenizer *)pTokenizer;
/* allocate and initialize the cursor struct */
perl_tokenizer_cursor *c;
c = (perl_tokenizer_cursor *) sqlite3_malloc(sizeof(*c));
memset(c, 0, sizeof(*c));
*ppCursor = &c->base;
/* special handling if working with utf8 strings */
if (MY_CXT.last_dbh_string_mode & DBD_SQLITE_STRING_MODE_UNICODE_ANY) {
/* data to keep track of byte positions */
c->currentByte = c->pInput = pInput;
c->currentChar = 0;
}
dbdimp_tokenizer.inc view on Meta::CPAN
ENTER;
SAVETMPS;
/* call the tokenizer coderef */
PUSHMARK(SP);
XPUSHs(perl_string);
PUTBACK;
n_retval = call_sv(t->coderef, G_SCALAR);
SPAGAIN;
/* store the cursor coderef returned by the tokenizer */
if (n_retval != 1) {
warn("tokenizer returned %d arguments, expected 1", n_retval);
}
c->coderef = newSVsv(POPs);
PUTBACK;
FREETMPS;
LEAVE;
return SQLITE_OK;
}
/*
** Close a tokenization cursor previously opened by a call to
** perl_tokenizer_Open() above.
*/
static int perl_tokenizer_Close(sqlite3_tokenizer_cursor *pCursor){
perl_tokenizer_cursor *c = (perl_tokenizer_cursor *) pCursor;
dTHX;
sv_free(c->coderef);
if (c->pToken) 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 perl_tokenizer_Open().
*/
static int perl_tokenizer_Next(
sqlite3_tokenizer_cursor *pCursor, /* Cursor returned by perl_tokenizer_Open */
const char **ppToken, /* OUT: Normalized text for token */
int *pnBytes, /* OUT: Number of bytes in normalized text */
int *piStartOffset, /* Starting offset of token. IN : char offset; OUT : byte offset */
int *piEndOffset, /* Ending offset of token. IN : char offset; OUT : byte offset */
int *piPosition /* OUT: Number of tokens returned before this one */
){
perl_tokenizer_cursor *c = (perl_tokenizer_cursor *) pCursor;
int result;
int n_retval;
char *token;
char *nextByte;
STRLEN n_a; /* this is required for older perls < 5.8.8 */
I32 hop;
dTHX;
dSP;
ENTER;
SAVETMPS;
/* call the cursor */
PUSHMARK(SP);
PUTBACK;
n_retval = call_sv(c->coderef, G_ARRAY);
SPAGAIN;
/* if we get back an empty list, there is no more token */
if (n_retval == 0) {
result = SQLITE_DONE;
}
/* otherwise, get token details from the return list */
else {
if (n_retval != 5) {
warn("tokenizer cursor returned %d arguments, expected 5", n_retval);
}
*piPosition = POPi;
*piEndOffset = POPi;
*piStartOffset = POPi;
*pnBytes = POPi;
token = POPpx;
if (c->pInput) { /* if working with utf8 data */
/* compute first hop : nb of chars from last position to the start of the token */
hop = *piStartOffset - c->currentChar;
dbdimp_tokenizer.inc view on Meta::CPAN
/* make sure we have enough storage for copying the token */
if (*pnBytes > c->nTokenAllocated ){
char *pNew;
c->nTokenAllocated = *pnBytes + 20;
pNew = sqlite3_realloc(c->pToken, c->nTokenAllocated);
if( !pNew ) return SQLITE_NOMEM;
c->pToken = pNew;
}
/* need to copy the token into the C cursor before perl frees that memory */
memcpy(c->pToken, token, *pnBytes);
*ppToken = c->pToken;
result = SQLITE_OK;
}
PUTBACK;
FREETMPS;
LEAVE;
dbdimp_virtual_table.inc view on Meta::CPAN
** The set of routines that implement the perl "module"
** (i.e support for virtual tables written in Perl)
************************************************************************/
typedef struct perl_vtab {
sqlite3_vtab base;
SV *perl_vtab_obj;
HV *functions;
} perl_vtab;
typedef struct perl_vtab_cursor {
sqlite3_vtab_cursor base;
SV *perl_cursor_obj;
} perl_vtab_cursor;
typedef struct perl_vtab_init {
SV *dbh;
const char *perl_class;
} perl_vtab_init;
/* auxiliary routine for generalized method calls. Arg "i" may be unused */
static int _call_perl_vtab_method(sqlite3_vtab *pVTab,
dbdimp_virtual_table.inc view on Meta::CPAN
PUTBACK;
FREETMPS;
LEAVE;
return SQLITE_OK;
}
static int perl_vt_Open(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
dTHX;
dSP;
int count;
int rc = SQLITE_ERROR;
SV *perl_cursor;
perl_vtab_cursor *cursor;
ENTER;
SAVETMPS;
/* allocate a perl_vtab_cursor structure */
cursor = (perl_vtab_cursor *) sqlite3_malloc(sizeof(*cursor));
if( cursor==NULL ) return SQLITE_NOMEM;
memset(cursor, 0, sizeof(*cursor));
/* call the ->OPEN() method */
PUSHMARK(SP);
XPUSHs( ((perl_vtab *) pVTab)->perl_vtab_obj);
PUTBACK;
count = call_method ("OPEN", G_SCALAR);
SPAGAIN;
if (count != 1) {
warn("vtab->OPEN() method returned %d vals instead of 1", count);
SP -= count;
goto cleanup;
}
perl_cursor = POPs;
if ( !sv_isobject(perl_cursor) ) {
warn("vtab->OPEN() method did not return a blessed cursor");
goto cleanup;
}
/* everything went OK */
rc = SQLITE_OK;
cleanup:
if (rc == SQLITE_OK) {
cursor->perl_cursor_obj = SvREFCNT_inc(perl_cursor);
*ppCursor = &cursor->base;
}
else {
sqlite3_free(cursor);
}
PUTBACK;
FREETMPS;
LEAVE;
return rc;
}
static int perl_vt_Close(sqlite3_vtab_cursor *pVtabCursor){
dTHX;
dSP;
perl_vtab_cursor *perl_pVTabCursor;
ENTER;
SAVETMPS;
/* Note : there is no explicit call to a CLOSE() method; if
needed, the Perl class can implement a DESTROY() method */
perl_pVTabCursor = (perl_vtab_cursor *) pVtabCursor;
SvREFCNT_dec(perl_pVTabCursor->perl_cursor_obj);
sqlite3_free(perl_pVTabCursor);
PUTBACK;
FREETMPS;
LEAVE;
return SQLITE_OK;
}
static int perl_vt_Filter( sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv ){
dTHX;
dSP;
dMY_CXT;
int i, count;
dbd_sqlite_string_mode_t string_mode = MY_CXT.last_dbh_string_mode;
ENTER;
SAVETMPS;
/* call the FILTER() method with ($idxNum, $idxStr, @args) */
PUSHMARK(SP);
XPUSHs(((perl_vtab_cursor *) pVtabCursor)->perl_cursor_obj);
XPUSHs(sv_2mortal(newSViv(idxNum)));
XPUSHs(sv_2mortal(newSVpv(idxStr, 0)));
for(i = 0; i < argc; i++) {
XPUSHs(stacked_sv_from_sqlite3_value(aTHX_ argv[i], string_mode));
}
PUTBACK;
count = call_method("FILTER", G_VOID);
SPAGAIN;
SP -= count;
PUTBACK;
FREETMPS;
LEAVE;
return SQLITE_OK;
}
static int perl_vt_Next(sqlite3_vtab_cursor *pVtabCursor){
dTHX;
dSP;
int count;
ENTER;
SAVETMPS;
/* call the next() method */
PUSHMARK(SP);
XPUSHs(((perl_vtab_cursor *) pVtabCursor)->perl_cursor_obj);
PUTBACK;
count = call_method ("NEXT", G_VOID);
SPAGAIN;
SP -= count;
PUTBACK;
FREETMPS;
LEAVE;
return SQLITE_OK;
}
static int perl_vt_Eof(sqlite3_vtab_cursor *pVtabCursor){
dTHX;
dSP;
int count;
int eof = 1;
ENTER;
SAVETMPS;
/* call the eof() method */
PUSHMARK(SP);
XPUSHs(((perl_vtab_cursor *) pVtabCursor)->perl_cursor_obj);
PUTBACK;
count = call_method ("EOF", G_SCALAR);
SPAGAIN;
if (count != 1) {
warn("cursor->EOF() method returned %d vals instead of 1", count);
SP -= count;
}
else {
SV *sv = POPs; /* need 2 lines, because this doesn't work : */
eof = SvTRUE(sv); /* eof = SvTRUE(POPs); # I don't understand why :-( */
}
PUTBACK;
FREETMPS;
LEAVE;
return eof;
}
static int perl_vt_Column(sqlite3_vtab_cursor *pVtabCursor,
sqlite3_context* context,
int col){
dTHX;
dSP;
int count;
int rc = SQLITE_ERROR;
ENTER;
SAVETMPS;
/* call the column() method */
PUSHMARK(SP);
XPUSHs(((perl_vtab_cursor *) pVtabCursor)->perl_cursor_obj);
XPUSHs(sv_2mortal(newSViv(col)));
PUTBACK;
count = call_method ("COLUMN", G_SCALAR);
SPAGAIN;
if (count != 1) {
warn("cursor->COLUMN() method returned %d vals instead of 1", count);
SP -= count;
sqlite3_result_error(context, "column error", 12);
}
else {
SV *result = POPs;
sqlite_set_result_for_vtable(aTHX_ context, result, 0 );
rc = SQLITE_OK;
}
PUTBACK;
FREETMPS;
LEAVE;
return rc;
}
static int perl_vt_Rowid( sqlite3_vtab_cursor *pVtabCursor,
sqlite3_int64 *pRowid ){
dTHX;
dSP;
int count;
int rc = SQLITE_ERROR;
ENTER;
SAVETMPS;
/* call the rowid() method */
PUSHMARK(SP);
XPUSHs(((perl_vtab_cursor *) pVtabCursor)->perl_cursor_obj);
PUTBACK;
count = call_method ("ROWID", G_SCALAR);
SPAGAIN;
if (count != 1) {
warn("cursor->ROWID() returned %d vals instead of 1", count);
SP -= count;
}
else {
*pRowid =POPi;
rc = SQLITE_OK;
}
PUTBACK;
FREETMPS;
LEAVE;
dbdimp_virtual_table.inc view on Meta::CPAN
/* call the _SQLITE_UPDATE() method */
PUSHMARK(SP);
XPUSHs(((perl_vtab *) pVTab)->perl_vtab_obj);
for(i = 0; i < argc; i++) {
XPUSHs(stacked_sv_from_sqlite3_value(aTHX_ argv[i], string_mode));
}
PUTBACK;
count = call_method ("_SQLITE_UPDATE", G_SCALAR);
SPAGAIN;
if (count != 1) {
warn("cursor->_SQLITE_UPDATE() returned %d vals instead of 1", count);
SP -= count;
}
else {
if (argc > 1 && sqlite3_value_type(argv[0]) == SQLITE_NULL
&& sqlite3_value_type(argv[1]) == SQLITE_NULL) {
/* this was an insert without any given rowid, so the result of
the method call must be passed in *pRowid*/
rowidsv = POPs;
if (!SvOK(rowidsv))
*pRowid = 0;
dbdimp_virtual_table.inc view on Meta::CPAN
return _call_perl_vtab_method(pVTab, "ROLLBACK_TO", point);
}
static sqlite3_module perl_vt_Module = {
1, /* iVersion */
perl_vt_Create, /* xCreate */
perl_vt_Connect, /* xConnect */
perl_vt_BestIndex, /* xBestIndex */
perl_vt_Disconnect, /* xDisconnect */
perl_vt_Drop, /* xDestroy */
perl_vt_Open, /* xOpen - open a cursor */
perl_vt_Close, /* xClose - close a cursor */
perl_vt_Filter, /* xFilter - configure scan constraints */
perl_vt_Next, /* xNext - advance a cursor */
perl_vt_Eof, /* xEof - check for end of scan */
perl_vt_Column, /* xColumn - read data */
perl_vt_Rowid, /* xRowid - read data */
perl_vt_Update, /* xUpdate (optional) */
perl_vt_Begin, /* xBegin (optional) */
perl_vt_Sync, /* xSync (optional) */
perl_vt_Commit, /* xCommit (optional) */
perl_vt_Rollback, /* xRollback (optional) */
perl_vt_FindFunction, /* xFindFunction (optional) */
perl_vt_Rename, /* xRename */
fts3_tokenizer.h view on Meta::CPAN
** 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.
*/
/* #include "sqlite3.h" */
fts3_tokenizer.h view on Meta::CPAN
** 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 or 1.
*/
int iVersion;
/*
** Create a new tokenizer. The values in the argv[] array are the
fts3_tokenizer.h view on Meta::CPAN
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. *piStartOffset should be set to the index of the first
fts3_tokenizer.h view on Meta::CPAN
**
** 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 */
);
/***********************************************************************
** Methods below this point are only available if iVersion>=1.
*/
/*
** Configure the language id of a tokenizer cursor.
*/
int (*xLanguageid)(sqlite3_tokenizer_cursor *pCsr, int iLangid);
};
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 */
};
int fts3_global_term_cnt(int iTerm, int iCol);
int fts3_term_cnt(int iTerm, int iCol);
#endif /* _FTS3_TOKENIZER_H_ */
/************** End of fts3_tokenizer.h **************************************/
lib/DBD/SQLite/GetInfo.pm view on Meta::CPAN
# NOTE: This is based purely on what sqlite3odbc supports.
#
# Static CA1: NEXT, ABSOLUTE, RELATIVE, BOOKMARK, LOCK_NO_CHANGE, POSITION, UPDATE, DELETE, REFRESH,
# BULK_ADD, BULK_UPDATE_BY_BOOKMARK, BULK_DELETE_BY_BOOKMARK = 466511
#
# Forward-only CA1: NEXT, BOOKMARK
#
# CA2: READ_ONLY_CONCURRENCY, LOCK_CONCURRENCY
144 => 0, # SQL_DYNAMIC_CURSOR_ATTRIBUTES1 - No dynamic cursor support
145 => 0, # SQL_DYNAMIC_CURSOR_ATTRIBUTES2 - No dynamic cursor support
146 => 1+8, # SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES1
147 => 1+2, # SQL_FORWARD_ONLY_CURSOR_ATTRIBUTES2
150 => 0, # SQL_KEYSET_CURSOR_ATTRIBUTES1 - No keyset cursor support
151 => 0, # SQL_KEYSET_CURSOR_ATTRIBUTES2 - No keyset cursor support
167 => 466511, # SQL_STATIC_CURSOR_ATTRIBUTES1
168 => 1+2, # SQL_STATIC_CURSOR_ATTRIBUTES2
27 => 'Y', # SQL_EXPRESSIONS_IN_ORDERBY - ORDER BY allows expressions
8 => 63, # SQL_FETCH_DIRECTION - Cursors support next, first, last, prior, absolute, relative
84 => 2, # SQL_FILE_USAGE - Single-tier driver, treats files as databases
81 => 1+2+8, # SQL_GETDATA_EXTENSIONS - Same as sqlite3odbc.c
88 => 3, # SQL_GROUP_BY - SELECT columns are independent of GROUP BY columns
28 => 4, # SQL_IDENTIFIER_CASE - Not case-sensitive, stored in mixed case
29 => '"', # SQL_IDENTIFIER_QUOTE_CHAR - Uses " for identifiers, though supports [] and ` as well
lib/DBD/SQLite/GetInfo.pm view on Meta::CPAN
115 => 1+8+16+32+64, # SQL_OJ_CAPABILITIES - Supports all OUTER JOINs except RIGHT & FULL
90 => 'N', # SQL_ORDER_BY_COLUMNS_IN_SELECT - ORDER BY columns don't have to be in the SELECT list
38 => 'Y', # SQL_OUTER_JOINS - Supports OUTER JOINs
153 => 2, # SQL_PARAM_ARRAY_ROW_COUNTS - Only has row counts for executed statements
154 => 3, # SQL_PARAM_ARRAY_SELECTS - No support for arrays of parameters
80 => 0, # SQL_POSITIONED_STATEMENTS - No support for positioned statements (WHERE CURRENT OF or SELECT FOR UPDATE)
79 => 31, # SQL_POS_OPERATIONS - Supports all SQLSetPos operations
21 => 'N', # SQL_PROCEDURES - No procedures
40 => '', # SQL_PROCEDURE_TERM - No procedures
93 => 4, # SQL_QUOTED_IDENTIFIER_CASE - Even quoted identifiers are case-insensitive
11 => 'N', # SQL_ROW_UPDATES - No fancy cursor update support
39 => '', # SQL_SCHEMA_TERM - No schemas
91 => 0, # SQL_SCHEMA_USAGE - No schemas
43 => 2, # SQL_SCROLL_CONCURRENCY - Updates/deletes on cursors lock the database
44 => 1+16, # SQL_SCROLL_OPTIONS - Only supports static & forward-only cursors
14 => '\\', # SQL_SEARCH_PATTERN_ESCAPE - Default escape character for LIKE is \
13 => \&sql_server_name, # SQL_SERVER_NAME - Just $dbh->{Name}
94 => '', # SQL_SPECIAL_CHARACTERS - Other drivers tend to stick to the ASCII/Latin-1 range, and SQLite uses all of
# the lower 7-bit punctuation for other things
155 => 7, # SQL_SQL92_DATETIME_FUNCTIONS - Supports CURRENT_(DATE|TIME|TIMESTAMP)
156 => 1+2+4+8, # SQL_SQL92_FOREIGN_KEY_DELETE_RULE - Support all ON DELETE options
157 => 1+2+4+8, # SQL_SQL92_FOREIGN_KEY_UPDATE_RULE - Support all ON UPDATE options
158 => 0, # SQL_SQL92_GRANT - No users; no support for GRANT
159 => 0, # SQL_SQL92_NUMERIC_VALUE_FUNCTIONS - No support for any of the listed functions
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
};
return $outputs;
}
sub OPEN {
my $self = shift;
my $class = ref $self;
my $cursor_class = $class . "::Cursor";
return $cursor_class->NEW($self, @_);
}
#----------------------------------------------------------------------
# methods for insert/delete/update
#----------------------------------------------------------------------
sub _SQLITE_UPDATE {
my ($self, $old_rowid, $new_rowid, @values) = @_;
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
sub NEW {
my ($class, $vtable, @args) = @_;
my $self = {vtable => $vtable,
args => \@args};
bless $self, $class;
}
sub FILTER {
my ($self, $idxNum, $idxStr, @values) = @_;
die "FILTER() should be redefined in cursor subclass";
}
sub EOF {
my ($self) = @_;
die "EOF() should be redefined in cursor subclass";
}
sub NEXT {
my ($self) = @_;
die "NEXT() should be redefined in cursor subclass";
}
sub COLUMN {
my ($self, $idxCol) = @_;
die "COLUMN() should be redefined in cursor subclass";
}
sub ROWID {
my ($self) = @_;
die "ROWID() should be redefined in cursor subclass";
}
1;
__END__
=head1 NAME
DBD::SQLite::VirtualTable -- SQLite virtual tables implemented in Perl
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
=over
=item *
the B<table> class implements methods for creating or connecting
a virtual table, for destroying it, for opening new searches, etc.
=item *
the B<cursor> class implements methods for performing a specific
SQL statement
=back
=head2 Methods
Most methods in both classes are not called directly from Perl
code : instead, they are callbacks, called from the sqlite kernel.
Following common Perl conventions, such methods have names in
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
that will be used
=over
=item a)
by the sqlite kernel to decide about the best search strategy
=item b)
by the cursor L</FILTER> method to produce the desired subset
of rows from the virtual table.
=back
By calling this method, the SQLite core is saying to the virtual table
that it needs to access some subset of the rows in the virtual table
and it wants to know the most efficient way to do that access. The
C<BEST_INDEX> method replies with information that the SQLite core can
then use to conduct an efficient search of the virtual table.
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
The C<$constraints> arrayref is used both for input and for output.
While iterating over the array, the method should
add the following keys into usable constraints :
=over
=item C<argvIndex>
An index into the C<@values> array that will be passed to
the cursor's L</FILTER> method. In other words, if the current
constraint corresponds to the SQL fragment C<WHERE ... AND foo < 123 ...>,
and the corresponding C<argvIndex> takes value 5, this means that
the C<FILTER> method will receive C<123> in C<$values[5]>.
=item C<omit>
A boolean telling to the sqlite core that it can safely omit
to double check that constraint before returning the resultset
to the calling program; this means that the FILTER method has fulfilled
the filtering job on that constraint and there is no need to do any
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
=item C<estimatedRows>
An integer giving the estimated number of rows returned by that query.
=back
=head3 OPEN
Called to instantiate a new cursor.
The default implementation appends C<"::Cursor"> to the current
classname and calls C<NEW()> within that cursor class.
=head3 _SQLITE_UPDATE
This is the dispatch method implementing the C<xUpdate()> callback
for virtual tables. The default implementation applies the algorithm
described in L<http://sqlite.org/vtab.html#xupdate> to decide
to call L</INSERT>, L</DELETE> or L</UPDATE>; so there is no reason
to override this method in subclasses.
=head3 INSERT
lib/DBD/SQLite/VirtualTable.pm view on Meta::CPAN
This method returns the database handle (C<$dbh>) associated with
the current virtual table.
=head1 CURSOR METHODS
=head2 Class methods
=head3 NEW
my $cursor = $cursor_class->NEW($vtable, @args)
Instantiates a new cursor.
The default implementation just returns a blessed hashref
with keys C<vtable> and C<args>.
=head2 Instance methods
=head3 FILTER
$cursor->FILTER($idxNum, $idxStr, @values);
This method begins a search of a virtual table.
The C<$idxNum> and C<$idxStr> arguments correspond to values returned
by L</BEST_INDEX> for the chosen index. The specific meanings of
those values are unimportant to SQLite, as long as C<BEST_INDEX> and
C<FILTER> agree on what that meaning is.
The C<BEST_INDEX> method may have requested the values of certain
expressions using the C<argvIndex> values of the
C<$constraints> list. Those values are passed to C<FILTER> through
the C<@values> array.
If the virtual table contains one or more rows that match the search
criteria, then the cursor must be left point at the first
row. Subsequent calls to L</EOF> must return false. If there are
no rows match, then the cursor must be left in a state that will cause
L</EOF> to return true. The SQLite engine will use the
L</COLUMN> and L</ROWID> methods to access that row content. The L</NEXT>
method will be used to advance to the next row.
=head3 EOF
This method must return false if the cursor currently points to a
valid row of data, or true otherwise. This method is called by the SQL
engine immediately after each L</FILTER> and L</NEXT> invocation.
=head3 NEXT
This method advances the cursor to the next row of a
result set initiated by L</FILTER>. If the cursor is already pointing at
the last row when this method is called, then the cursor no longer
points to valid data and a subsequent call to the L</EOF> method must
return true. If the cursor is successfully advanced to
another row of content, then subsequent calls to L</EOF> must return
false.
=head3 COLUMN
my $value = $cursor->COLUMN($idxCol);
The SQLite core invokes this method in order to find the value for the
N-th column of the current row. N is zero-based so the first column is
numbered 0.
=head3 ROWID
my $value = $cursor->ROWID;
Returns the I<rowid> of row that the cursor is currently pointing at.
=head1 SEE ALSO
L<SQLite::VirtualTable> is another module for virtual tables written
in Perl, but designed for the reverse use case : instead of starting a
Perl program, and embedding the SQLite library into it, the intended
use is to start an sqlite program, and embed the Perl interpreter
into it.
lib/DBD/SQLite/VirtualTable/PerlData.pm view on Meta::CPAN
# build a method coderef to fetch matching rows
my $perl_code = 'sub {my ($self, $i) = @_; my $row = $self->row($i); '
. $idxStr
. '}';
# print STDERR "PERL CODE:\n", $perl_code, "\n";
$self->{is_wanted_row} = do { no warnings; eval $perl_code }
or die "couldn't eval q{$perl_code} : $@";
# position the cursor to the first matching row (or to eof)
$self->{row_ix} = -1;
$self->NEXT;
}
sub EOF {
my ($self) = @_;
return $self->{row_ix} > $#${$self->{vtable}{rows}};
}
** ^This interface disables all automatic extensions previously
** registered using [sqlite3_auto_extension()].
*/
SQLITE_API void sqlite3_reset_auto_extension(void);
/*
** 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
** KEYWORDS: sqlite3_module {virtual table module}
**
** This structure, sometimes called a "virtual table module",
** defines the implementation of a [virtual table].
** This structure consists mostly of methods for the 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);
/* The methods above are in version 1 of the sqlite_module object. Those
**
** ^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.
*/
struct sqlite3_vtab {
const sqlite3_module *pModule; /* The module for this virtual table */
int nRef; /* Number of open cursors */
char *zErrMsg; /* Error message from sqlite3_mprintf() */
/* Virtual table implementations will typically add additional fields */
};
/*
** CAPI3REF: Virtual Table Cursor Object
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
**
** Every [virtual table 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
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
** by the [sqlite3_module.xClose | xClose] method. Cursors are used
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
** 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.
*/
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
**
** ^The [xCreate] and [xConnect] methods of a
** [virtual table module] call this interface
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
/*
** CAPI3REF: Flush caches to disk mid-transaction
** METHOD: sqlite3
**
** ^If a write-transaction is open on [database connection] D when the
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
** pages in the pager-cache that are not currently in use are written out
** to disk. A dirty page may be in use if a database cursor created by an
** active SQL statement is reading from it, or if it is page 1 of a database
** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
** interface flushes caches for all schemas - "main", "temp", and
** any [attached] databases.
**
** ^If this function needs to obtain extra database locks before dirty pages
** can be flushed to disk, it does so. ^If those locks cannot be obtained
** immediately and there is a busy-handler callback configured, it is invoked
** in the usual manner. ^If the required lock still cannot be obtained, then
** the database is skipped and an attempt made to flush any dirty pages
** CAPI3REF: Session Object Handle
**
** An instance of this object is a [session] that can be used to
** record changes to a database.
*/
typedef struct sqlite3_session sqlite3_session;
/*
** CAPI3REF: Changeset Iterator Handle
**
** An instance of this object acts as a cursor for iterating
** over the elements of a [changeset] or [patchset].
*/
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
/*
** CAPI3REF: Create A New Session Object
** CONSTRUCTOR: sqlite3_session
**
** Create a new session object attached to database handle db. If successful,
** a pointer to the new object is written to *ppSession and SQLITE_OK is
#define BTREE_APPLICATION_ID 8
#define BTREE_DATA_VERSION 15 /* A virtual meta-value */
/*
** Kinds of hints that can be passed into the sqlite3BtreeCursorHint()
** interface.
**
** BTREE_HINT_RANGE (arguments: Expr*, Mem*)
**
** The first argument is an Expr* (which is guaranteed to be constant for
** the lifetime of the cursor) that defines constraints on which rows
** might be fetched with this cursor. The Expr* tree may contain
** TK_REGISTER nodes that refer to values stored in the array of registers
** passed as the second parameter. In other words, if Expr.op==TK_REGISTER
** then the value of the node is the value in Mem[pExpr.iTable]. Any
** TK_COLUMN node in the expression tree refers to the Expr.iColumn-th
** column of the b-tree of the cursor. The Expr tree will not contain
** any function calls nor subqueries nor references to b-trees other than
** the cursor being hinted.
**
** The design of the _RANGE hint is aid b-tree implementations that try
** to prefetch content from remote machines - to provide those
** implementations with limits on what needs to be prefetched and thereby
** reduce network bandwidth.
**
** Note that BTREE_HINT_FLAGS with BTREE_BULKLOAD is the only hint used by
** standard SQLite. The other hints are provided for extensions that use
** the SQLite parser and code generator but substitute their own storage
** engine.
*/
#define BTREE_HINT_RANGE 0 /* Range constraints on queries */
/*
** Values that may be OR'd together to form the argument to the
** BTREE_HINT_FLAGS hint for sqlite3BtreeCursorHint():
**
** The BTREE_BULKLOAD flag is set on index cursors when the index is going
** to be filled with content that is already in sorted order.
**
** The BTREE_SEEK_EQ flag is set on cursors that will get OP_SeekGE or
** OP_SeekLE opcodes for a range search, but where the range of entries
** selected will all have the same key. In other words, the cursor will
** be used only for equality key searches.
**
*/
#define BTREE_BULKLOAD 0x00000001 /* Used to full index in sorted order */
#define BTREE_SEEK_EQ 0x00000002 /* EQ seeks only - no range seeks */
/*
** Flags passed as the third argument to sqlite3BtreeCursor().
**
** For read-only cursors the wrFlag argument is always zero. For read-write
** cursors it may be set to either (BTREE_WRCSR|BTREE_FORDELETE) or just
** (BTREE_WRCSR). If the BTREE_FORDELETE bit is set, then the cursor will
** only be used by SQLite for the following:
**
** * to seek to and then delete specific entries, and/or
**
** * to read values that will be used to create keys that other
** BTREE_FORDELETE cursors will seek to and delete.
**
** The BTREE_FORDELETE flag is an optimization hint. It is not used by
** by this, the native b-tree engine of SQLite, but it is available to
** alternative storage engines that might be substituted in place of this
** b-tree system. For alternative storage engines in which a delete of
** the main table row automatically deletes corresponding index rows,
** the FORDELETE flag hint allows those alternative storage engines to
** skip a lot of work. Namely: FORDELETE cursors may treat all SEEK
** and DELETE operations as no-ops, and any READ operation against a
** FORDELETE cursor may return a null row: 0x01 0x00.
*/
#define BTREE_WRCSR 0x00000004 /* read-write cursor */
#define BTREE_FORDELETE 0x00000008 /* Cursor is for seek/delete only */
SQLITE_PRIVATE int sqlite3BtreeCursor(
Btree*, /* BTree containing table to open */
Pgno 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 BtCursor *sqlite3BtreeFakeValidCursor(void);
SQLITE_PRIVATE int sqlite3BtreeCursorSize(void);
SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor*);
SQLITE_PRIVATE void sqlite3BtreeCursorHintFlags(BtCursor*, unsigned);
#ifdef SQLITE_ENABLE_CURSOR_HINTS
SQLITE_PRIVATE void sqlite3BtreeCursorHint(BtCursor*, int, ...);
#endif
SQLITE_PRIVATE int sqlite3BtreeCloseCursor(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeIndexMoveto(
BtCursor*,
UnpackedRecord *pUnKey,
int *pRes
);
SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor*);
SQLITE_PRIVATE int sqlite3BtreeCursorRestore(BtCursor*, int*);
SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor*, u8 flags);
/* Allowed flags for sqlite3BtreeDelete() and sqlite3BtreeInsert() */
#define BTREE_SAVEPOSITION 0x02 /* Leave cursor pointing at NEXT or PREV */
#define BTREE_AUXDELETE 0x04 /* not the primary delete operation */
#define BTREE_APPEND 0x08 /* Insert is likely an append */
#define BTREE_PREFORMAT 0x80 /* Inserted data is a preformated cell */
/* An instance of the BtreePayload object describes the content of a single
** entry in either an index or table btree.
**
** Index btrees (used for indexes and also WITHOUT ROWID tables) contain
** an arbitrary key and no data. These btrees have pKey,nKey set to the
** key and the pData,nData,nZero fields are uninitialized. The aMem,nMem
typedef struct VdbeOp VdbeOp;
/*
** A sub-routine used to implement a trigger program.
*/
struct SubProgram {
VdbeOp *aOp; /* Array of opcodes for sub-program */
int nOp; /* Elements in aOp[] */
int nMem; /* Number of memory cells required */
int nCsr; /* Number of cursors required */
u8 *aOnce; /* Array of OP_Once flags */
void *token; /* id that may be used to recursive triggers */
SubProgram *pNext; /* Next sub-program already visited */
};
/*
** A smaller version of VdbeOp used for the VdbeAddOpList() function because
** it takes up less space.
*/
struct VdbeOpList {
#define OP_ResultRow 84 /* synopsis: output=r[P1@P2] */
#define OP_CollSeq 85
#define OP_AddImm 86 /* synopsis: r[P1]=r[P1]+P2 */
#define OP_RealAffinity 87
#define OP_Cast 88 /* synopsis: affinity(r[P1]) */
#define OP_Permutation 89
#define OP_Compare 90 /* synopsis: r[P1@P3] <-> r[P2@P3] */
#define OP_IsTrue 91 /* synopsis: r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4 */
#define OP_ZeroOrNull 92 /* synopsis: r[P2] = 0 OR NULL */
#define OP_Offset 93 /* synopsis: r[P3] = sqlite_offset(P1) */
#define OP_Column 94 /* synopsis: r[P3]=PX cursor P1 column P2 */
#define OP_TypeCheck 95 /* synopsis: typecheck(r[P1@P2]) */
#define OP_Affinity 96 /* synopsis: affinity(r[P1@P2]) */
#define OP_MakeRecord 97 /* synopsis: r[P3]=mkrec(r[P1@P2]) */
#define OP_Count 98 /* synopsis: r[P2]=count() */
#define OP_ReadCookie 99
#define OP_SetCookie 100
#define OP_ReopenIdx 101 /* synopsis: root=P2 iDb=P3 */
#define OP_BitAnd 102 /* same as TK_BITAND, synopsis: r[P3]=r[P1]&r[P2] */
#define OP_BitOr 103 /* same as TK_BITOR, synopsis: r[P3]=r[P1]|r[P2] */
#define OP_ShiftLeft 104 /* same as TK_LSHIFT, synopsis: r[P3]=r[P2]<<r[P1] */
#define OP_Remainder 110 /* same as TK_REM, synopsis: r[P3]=r[P2]%r[P1] */
#define OP_Concat 111 /* same as TK_CONCAT, synopsis: r[P3]=r[P2]+r[P1] */
#define OP_OpenRead 112 /* synopsis: root=P2 iDb=P3 */
#define OP_OpenWrite 113 /* synopsis: root=P2 iDb=P3 */
#define OP_BitNot 114 /* same as TK_BITNOT, synopsis: r[P2]= ~r[P1] */
#define OP_OpenDup 115
#define OP_OpenAutoindex 116 /* synopsis: nColumn=P2 */
#define OP_String8 117 /* same as TK_STRING, synopsis: r[P2]='P4' */
#define OP_OpenEphemeral 118 /* synopsis: nColumn=P2 */
#define OP_SorterOpen 119
#define OP_SequenceTest 120 /* synopsis: if( cursor[P1].ctr++ ) pc = P2 */
#define OP_OpenPseudo 121 /* synopsis: P3 columns in r[P2] */
#define OP_Close 122
#define OP_ColumnsUsed 123
#define OP_SeekScan 124 /* synopsis: Scan-ahead up to P1 rows */
#define OP_SeekHit 125 /* synopsis: set P2<=seekHit<=P3 */
#define OP_Sequence 126 /* synopsis: r[P2]=cursor[P1].ctr++ */
#define OP_NewRowid 127 /* synopsis: r[P2]=rowid */
#define OP_Insert 128 /* synopsis: intkey=r[P3] data=r[P2] */
#define OP_RowCell 129
#define OP_Delete 130
#define OP_ResetCount 131
#define OP_SorterCompare 132 /* synopsis: if key(P1)!=trim(r[P3],P4) goto P2 */
#define OP_SorterData 133 /* synopsis: r[P2]=data */
#define OP_RowData 134 /* synopsis: r[P2]=data */
#define OP_Rowid 135 /* synopsis: r[P2]=PX rowid of P1 */
#define OP_NullRow 136
**
** Expr.x.pList is a list of arguments if the expression is an SQL function,
** a CASE expression or an IN expression of the form "<lhs> IN (<y>, <z>...)".
** Expr.x.pSelect is used if the expression is a sub-select or an expression of
** the form "<lhs> IN (SELECT ...)". If the EP_xIsSelect bit is set in the
** Expr.flags mask, then Expr.x.pSelect is valid. Otherwise, Expr.x.pList is
** valid.
**
** 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 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
} x;
/* If the EP_Reduced flag is set in the Expr.flags mask, then no
** space is allocated for the fields below this point. An attempt to
** access them will result in a segfault or malfunction.
*********************************************************************/
#if SQLITE_MAX_EXPR_DEPTH>0
int nHeight; /* Height of the tree headed by this node */
#endif
int iTable; /* TK_COLUMN: cursor number of table holding column
** TK_REGISTER: register number
** TK_TRIGGER: 1 -> new, 0 -> old
** EP_Unlikely: 134217728 times likelihood
** TK_IN: ephemeral table holding RHS
** TK_SELECT_COLUMN: Number of columns on the LHS
** TK_SELECT: 1st register of result vector */
ynVar iColumn; /* TK_COLUMN: column index. -1 for rowid.
** TK_VARIABLE: variable number (always >= 1).
** TK_SELECT_COLUMN: column of the result vector */
i16 iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */
unsigned isRecursive :1; /* True for recursive reference in WITH */
unsigned fromDDL :1; /* Comes from sqlite_schema */
unsigned isCte :1; /* This is a CTE */
unsigned notCte :1; /* This item may not match a CTE */
unsigned isUsing :1; /* u3.pUsing is valid */
unsigned isOn :1; /* u3.pOn was once valid and non-NULL */
unsigned isSynthUsing :1; /* u3.pUsing is synthesized from NATURAL */
unsigned isNestedFrom :1; /* pSelect is a SF_NestedFrom subquery */
unsigned rowidUsed :1; /* The ROWID of this table is referenced */
} fg;
int iCursor; /* The VDBE cursor number used to access this table */
union {
Expr *pOn; /* fg.isUsing==0 => The ON clause of a join */
IdList *pUsing; /* fg.isUsing==1 => The USING clause of a join */
} u3;
Bitmask colUsed; /* Bit N set if column N used. Details above for N>62 */
union {
char *zIndexedBy; /* Identifier from "INDEXED BY <zIndex>" clause */
ExprList *pFuncArg; /* Arguments to table-valued-function */
u32 nRow; /* Number of rows in a VALUES clause */
} u1;
** The next group of fields stores intermediate data. */
void *pToFree; /* Free memory when deleting the Upsert object */
/* All fields above are owned by the Upsert object and must be freed
** when the Upsert is destroyed. The fields below are used to transfer
** information from the INSERT processing down into the UPDATE processing
** while generating code. The fields below are owned by the INSERT
** statement and will be freed by INSERT processing. */
Index *pUpsertIdx; /* UNIQUE constraint specified by pUpsertTarget */
SrcList *pUpsertSrc; /* Table to be updated */
int regData; /* First register holding array of VALUES */
int iDataCur; /* Index of the data cursor */
int iIdxCur; /* Index of the first index cursor */
};
/*
** An instance of the following structure contains all information
** needed to generate code for a single SELECT statement.
**
** See the header comment on the computeLimitRegisters() routine for a
** detailed description of the meaning of the iLimit and iOffset fields.
**
** addrOpenEphm[] entries contain the address of OP_OpenEphemeral opcodes.
** Store the first column of the first result row
** in register pDest->iSDParm then abandon the rest
** of the query. This destination implies "LIMIT 1".
**
** SRT_Set The result must be a single column. Store each
** row of result as the key in table pDest->iSDParm.
** Apply the affinity pDest->affSdst before storing
** results. Used to implement "IN (SELECT ...)".
**
** SRT_EphemTab Create an temporary table pDest->iSDParm and store
** the result there. The cursor is left open after
** returning. This is like SRT_Table except that
** this destination uses OP_OpenEphemeral to create
** the table first.
**
** SRT_Coroutine Generate a co-routine that returns a new row of
** results each time it is invoked. The entry point
** of the co-routine is stored in register pDest->iSDParm
** and the result row is stored in pDest->nDest registers
** starting with pDest->iSdst.
**
** or the name of a virtual generated column, and if X is in scope such that
** the value of the expression can simply be read from the index, then
** there is an instance of this object on the Parse.pIdxExpr list.
**
** During code generation, while generating code to evaluate expressions,
** this list is consulted and if a matching expression is found, the value
** is read from the index rather than being recomputed.
*/
struct IndexedExpr {
Expr *pExpr; /* The expression contained in the index */
int iDataCur; /* The data cursor associated with the index */
int iIdxCur; /* The index cursor */
int iIdxCol; /* The index column that contains value of pExpr */
u8 bMaybeNullRow; /* True if we need an OP_IfNullRow check */
u8 aff; /* Affinity of the pExpr expression */
IndexedExpr *pIENext; /* Next in a list of all indexed expressions */
#ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS
const char *zIdxName; /* Name of index, used only for bytecode comments */
#endif
};
/*
u8 bHasWith; /* True if statement contains WITH */
#if defined(SQLITE_DEBUG) || defined(SQLITE_COVERAGE_TEST)
u8 earlyCleanup; /* OOM inside sqlite3ParserAddCleanup() */
#endif
#ifdef SQLITE_DEBUG
u8 ifNotExists; /* Might be true if IF NOT EXISTS. Assert()s only */
#endif
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 szOpAlloc; /* Bytes of memory space allocated for Vdbe.aOp[] */
int iSelfTab; /* Table associated with an index on expr, or negative
** of the base register during check-constraint eval */
int nLabel; /* The *negative* of the number of labels used */
int nLabelAlloc; /* Number of slots in aLabel */
int *aLabel; /* Space to hold the labels */
ExprList *pConstExpr;/* Constant expressions */
IndexedExpr *pIdxEpr;/* List of expressions used by active indexes */
IndexedExpr *pIdxPartExpr; /* Exprs constrained by index WHERE clauses */
#define OPFLAG_NOCHNG 0x01 /* OP_VColumn nochange for UPDATE */
#define OPFLAG_EPHEM 0x01 /* OP_Column: Ephemeral output is ok */
#define OPFLAG_LASTROWID 0x20 /* Set to update db->lastRowid */
#define OPFLAG_ISUPDATE 0x04 /* This OP_Insert is an sql UPDATE */
#define OPFLAG_APPEND 0x08 /* This is likely to be an append */
#define OPFLAG_USESEEKRESULT 0x10 /* Try to avoid a seek in BtreeInsert() */
#define OPFLAG_ISNOOP 0x40 /* OP_Delete does pre-update-hook only */
#define OPFLAG_LENGTHARG 0x40 /* OP_Column only used for length() */
#define OPFLAG_TYPEOFARG 0x80 /* OP_Column only used for typeof() */
#define OPFLAG_BYTELENARG 0xc0 /* OP_Column only for octet_length() */
#define OPFLAG_BULKCSR 0x01 /* OP_Open** used to open bulk cursor */
#define OPFLAG_SEEKEQ 0x02 /* OP_Open** cursor uses EQ seek only */
#define OPFLAG_FORDELETE 0x08 /* OP_Open should use BTREE_FORDELETE */
#define OPFLAG_P2ISREG 0x10 /* P2 to OP_Open** is a register number */
#define OPFLAG_PERMUTE 0x01 /* OP_Compare: use the permutation */
#define OPFLAG_SAVEPOSITION 0x02 /* OP_Delete/Insert: save cursor pos */
#define OPFLAG_AUXDELETE 0x04 /* OP_Delete: index in a DELETE op */
#define OPFLAG_NOCHNG_MAGIC 0x6d /* OP_MakeRecord: serialtype 10 is ok */
#define OPFLAG_PREFORMAT 0x80 /* OP_Insert uses preformatted cell */
/*
** Each trigger present in the database schema is stored as an instance of
** struct Trigger.
**
** Pointers to instances of struct Trigger are stored in two ways.
** 1. In the "trigHash" hash table (part of the sqlite3* that represents the
Parse *pParse; /* Parser context. */
int (*xExprCallback)(Walker*, Expr*); /* Callback for expressions */
int (*xSelectCallback)(Walker*,Select*); /* Callback for SELECTs */
void (*xSelectCallback2)(Walker*,Select*);/* Second callback for SELECTs */
int walkerDepth; /* Number of subqueries */
u16 eCode; /* A small processing code */
u16 mWFlags; /* Use-dependent flags */
union { /* Extra data for callback */
NameContext *pNC; /* Naming context */
int n; /* A counter */
int iCur; /* A cursor number */
SrcList *pSrcList; /* FROM clause */
struct CCurHint *pCCurHint; /* Used by codeCursorHint() */
struct RefSrcList *pRefSrcList; /* sqlite3ReferencesSrcList() */
int *aiCol; /* array of column indexes */
struct IdxCover *pIdxCover; /* Check for index coverage */
ExprList *pGroupBy; /* GROUP BY clause */
Select *pSelect; /* HAVING to WHERE clause ctx */
struct WindowRewrite *pRewrite; /* Window rewrite context */
struct WhereConst *pConst; /* WHERE clause constants */
struct RenameCtx *pRename; /* RENAME COLUMN context */
u8 eExclude; /* TK_NO, TK_CURRENT, TK_TIES, TK_GROUP, or 0 */
Expr *pStart; /* Expression for "<expr> PRECEDING" */
Expr *pEnd; /* Expression for "<expr> FOLLOWING" */
Window **ppThis; /* Pointer to this object in Select.pWin list */
Window *pNextWin; /* Next window function belonging to this SELECT */
Expr *pFilter; /* The FILTER expression */
FuncDef *pWFunc; /* The function */
int iEphCsr; /* Partition buffer or Peer buffer */
int regAccum; /* Accumulator */
int regResult; /* Interim result */
int csrApp; /* Function cursor (used by min/max) */
int regApp; /* Function register (also used by min/max) */
int regPart; /* Array of registers for PARTITION BY values */
Expr *pOwner; /* Expression object this window is attached to */
int nBufferCol; /* Number of columns in buffer table */
int iArgCol; /* Offset of first argument for this function */
int regOne; /* Register containing constant value 1 */
int regStartRowid;
int regEndRowid;
u8 bExprArgs; /* Defer evaluation of window function arguments
** due to the SQLITE_SUBTYPE flag */
/* Opaque type used by code in vdbesort.c */
typedef struct VdbeSorter VdbeSorter;
/* Elements of the linked list at Vdbe.pAuxData */
typedef struct AuxData AuxData;
/* A cache of large TEXT or BLOB values in a VdbeCursor */
typedef struct VdbeTxtBlbCache VdbeTxtBlbCache;
/* Types of VDBE cursors */
#define CURTYPE_BTREE 0
#define CURTYPE_SORTER 1
#define CURTYPE_VTAB 2
#define CURTYPE_PSEUDO 3
/*
** A VdbeCursor is an superclass (a wrapper) for various cursor objects:
**
** * A b-tree cursor
** - In the main database or in an ephemeral database
** - On either an index or a table
** * A sorter
** * A virtual table
** * A one-row "pseudotable" stored in a single register
*/
typedef struct VdbeCursor VdbeCursor;
struct VdbeCursor {
u8 eCurType; /* One of the CURTYPE_* values above */
i8 iDb; /* Index of cursor database in db->aDb[] */
u8 nullRow; /* True if pointing to a row with no data */
u8 deferredMoveto; /* A call to sqlite3BtreeMoveto() is needed */
u8 isTable; /* True for rowid tables. False for indexes */
#ifdef SQLITE_DEBUG
u8 seekOp; /* Most recent seek operation on this cursor */
u8 wrFlag; /* The wrFlag argument to sqlite3BtreeCursor() */
#endif
Bool isEphemeral:1; /* True for an ephemeral table */
Bool useRandomRowid:1; /* Generate new record numbers semi-randomly */
Bool isOrdered:1; /* True if the table is not BTREE_UNORDERED */
Bool noReuse:1; /* OpenEphemeral may not reuse this cursor */
Bool colCache:1; /* pCache pointer is initialized and non-NULL */
u16 seekHit; /* See the OP_SeekHit and OP_IfNoHope opcodes */
union { /* pBtx for isEphermeral. pAltMap otherwise */
Btree *pBtx; /* Separate file holding temporary table */
u32 *aAltMap; /* Mapping from table to index column numbers */
} ub;
i64 seqCount; /* Sequence counter */
/* Cached OP_Column parse information is only valid if cacheStatus matches
** Vdbe.cacheCtr. Vdbe.cacheCtr will never take on the value of
** CACHE_STALE (0) and so setting cacheStatus=CACHE_STALE guarantees that
** the cache is out of date. */
u32 cacheStatus; /* Cache is valid if this matches Vdbe.cacheCtr */
int seekResult; /* Result of previous sqlite3BtreeMoveto() or 0
** if there have been no prior seeks on the cursor. */
/* seekResult does not distinguish between "no seeks have ever occurred
** on this cursor" and "the most recent seek was an exact match".
** For CURTYPE_PSEUDO, seekResult is the register holding the record */
/* When a new VdbeCursor is allocated, only the fields above are zeroed.
** The fields that follow are uninitialized, and must be individually
** initialized prior to first use. */
VdbeCursor *pAltCursor; /* Associated index cursor from which to read */
union {
BtCursor *pCursor; /* CURTYPE_BTREE or _PSEUDO. Btree cursor */
sqlite3_vtab_cursor *pVCur; /* CURTYPE_VTAB. Vtab cursor */
VdbeSorter *pSorter; /* CURTYPE_SORTER. Sorter object */
} uc;
KeyInfo *pKeyInfo; /* Info about index keys needed by index cursors */
u32 iHdrOffset; /* Offset to next unparsed byte of the header */
Pgno pgnoRoot; /* Root page of the open btree cursor */
i16 nField; /* Number of fields in the header */
u16 nHdrParsed; /* Number of header fields parsed so far */
i64 movetoTarget; /* Argument to the deferred sqlite3BtreeMoveto() */
u32 *aOffset; /* Pointer to aType[nField] */
const u8 *aRow; /* Data for the current row, if all on one page */
u32 payloadSize; /* Total number of bytes in the record */
u32 szRow; /* Byte available in aRow */
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
u64 maskUsed; /* Mask of columns used by this cursor */
#endif
VdbeTxtBlbCache *pCache; /* Cache of large TEXT or BLOB values */
/* 2*nField extra array elements allocated for aType[], beyond the one
** static element declared in the structure. nField total array slots for
** aType[] and nField+1 array slots for aOffset[] */
u32 aType[1]; /* Type values record decode. MUST BE LAST */
};
/* Return true if P is a null-only cursor
*/
#define IsNullCursor(P) \
((P)->eCurType==CURTYPE_PSEUDO && (P)->nullRow && (P)->seekResult==0)
/*
** A value for VdbeCursor.cacheStatus that means the cache is always invalid.
*/
#define CACHE_STALE 0
/*
**
** The currently executing frame is stored in Vdbe.pFrame. Vdbe.pFrame is
** set to NULL if the currently executing frame is the main program.
*/
typedef struct VdbeFrame VdbeFrame;
struct VdbeFrame {
Vdbe *v; /* VM this frame belongs to */
VdbeFrame *pParent; /* Parent of this frame, or NULL if parent is main */
Op *aOp; /* Program instructions for parent frame */
Mem *aMem; /* Array of memory cells for parent frame */
VdbeCursor **apCsr; /* Array of Vdbe cursors for parent frame */
u8 *aOnce; /* Bitmask used by OP_Once */
void *token; /* Copy of SubProgram.token */
i64 lastRowid; /* Last insert rowid (sqlite3.lastRowid) */
AuxData *pAuxData; /* Linked list of auxdata allocations */
#if SQLITE_DEBUG
u32 iFrameMagic; /* magic number for sanity checking */
#endif
int nCursor; /* Number of entries in apCsr */
int pc; /* Program Counter in parent (calling) frame */
int nOp; /* Size of aOp array */
int nMem; /* Number of entries in aMem */
int nChildMem; /* Number of memory cells for child frame */
int nChildCsr; /* Number of cursors for child frame */
i64 nChange; /* Statement changes (Vdbe.nChange) */
i64 nDbChange; /* Value of db->nChange */
};
/* Magic number for sanity checking on VdbeFrame objects */
#define SQLITE_FRAME_MAGIC 0x879fb71e
/*
** Return a pointer to the array of registers allocated for use
** by a VdbeFrame.
int pc; /* The program counter */
int rc; /* Value to return */
i64 nChange; /* Number of db changes made since last reset */
int iStatement; /* Statement number (or 0 if has no opened stmt) */
i64 iCurrentTime; /* Value of julianday('now') for this statement */
i64 nFkConstraint; /* Number of imm. FK constraints this VM */
i64 nStmtDefCons; /* Number of def. constraints when stmt started */
i64 nStmtDefImmCons; /* Number of def. imm constraints when stmt started */
Mem *aMem; /* The memory locations */
Mem **apArg; /* Arguments to currently executing user function */
VdbeCursor **apCsr; /* One element of this array for each open cursor */
Mem *aVar; /* Values for the OP_Variable opcode. */
/* When allocating a new Vdbe object, all of the fields below should be
** initialized to zero or NULL */
Op *aOp; /* Space to hold the virtual machine's program */
int nOp; /* Number of instructions in the program */
int nOpAlloc; /* Slots allocated for aOp[] */
Mem *aColName; /* Column names to return */
Mem *pResultRow; /* Current output row */
/* 84 */ "ResultRow" OpHelp("output=r[P1@P2]"),
/* 85 */ "CollSeq" OpHelp(""),
/* 86 */ "AddImm" OpHelp("r[P1]=r[P1]+P2"),
/* 87 */ "RealAffinity" OpHelp(""),
/* 88 */ "Cast" OpHelp("affinity(r[P1])"),
/* 89 */ "Permutation" OpHelp(""),
/* 90 */ "Compare" OpHelp("r[P1@P3] <-> r[P2@P3]"),
/* 91 */ "IsTrue" OpHelp("r[P2] = coalesce(r[P1]==TRUE,P3) ^ P4"),
/* 92 */ "ZeroOrNull" OpHelp("r[P2] = 0 OR NULL"),
/* 93 */ "Offset" OpHelp("r[P3] = sqlite_offset(P1)"),
/* 94 */ "Column" OpHelp("r[P3]=PX cursor P1 column P2"),
/* 95 */ "TypeCheck" OpHelp("typecheck(r[P1@P2])"),
/* 96 */ "Affinity" OpHelp("affinity(r[P1@P2])"),
/* 97 */ "MakeRecord" OpHelp("r[P3]=mkrec(r[P1@P2])"),
/* 98 */ "Count" OpHelp("r[P2]=count()"),
/* 99 */ "ReadCookie" OpHelp(""),
/* 100 */ "SetCookie" OpHelp(""),
/* 101 */ "ReopenIdx" OpHelp("root=P2 iDb=P3"),
/* 102 */ "BitAnd" OpHelp("r[P3]=r[P1]&r[P2]"),
/* 103 */ "BitOr" OpHelp("r[P3]=r[P1]|r[P2]"),
/* 104 */ "ShiftLeft" OpHelp("r[P3]=r[P2]<<r[P1]"),
/* 110 */ "Remainder" OpHelp("r[P3]=r[P2]%r[P1]"),
/* 111 */ "Concat" OpHelp("r[P3]=r[P2]+r[P1]"),
/* 112 */ "OpenRead" OpHelp("root=P2 iDb=P3"),
/* 113 */ "OpenWrite" OpHelp("root=P2 iDb=P3"),
/* 114 */ "BitNot" OpHelp("r[P2]= ~r[P1]"),
/* 115 */ "OpenDup" OpHelp(""),
/* 116 */ "OpenAutoindex" OpHelp("nColumn=P2"),
/* 117 */ "String8" OpHelp("r[P2]='P4'"),
/* 118 */ "OpenEphemeral" OpHelp("nColumn=P2"),
/* 119 */ "SorterOpen" OpHelp(""),
/* 120 */ "SequenceTest" OpHelp("if( cursor[P1].ctr++ ) pc = P2"),
/* 121 */ "OpenPseudo" OpHelp("P3 columns in r[P2]"),
/* 122 */ "Close" OpHelp(""),
/* 123 */ "ColumnsUsed" OpHelp(""),
/* 124 */ "SeekScan" OpHelp("Scan-ahead up to P1 rows"),
/* 125 */ "SeekHit" OpHelp("set P2<=seekHit<=P3"),
/* 126 */ "Sequence" OpHelp("r[P2]=cursor[P1].ctr++"),
/* 127 */ "NewRowid" OpHelp("r[P2]=rowid"),
/* 128 */ "Insert" OpHelp("intkey=r[P3] data=r[P2]"),
/* 129 */ "RowCell" OpHelp(""),
/* 130 */ "Delete" OpHelp(""),
/* 131 */ "ResetCount" OpHelp(""),
/* 132 */ "SorterCompare" OpHelp("if key(P1)!=trim(r[P3],P4) goto P2"),
/* 133 */ "SorterData" OpHelp("r[P2]=data"),
/* 134 */ "RowData" OpHelp("r[P2]=data"),
/* 135 */ "Rowid" OpHelp("r[P2]=PX rowid of P1"),
/* 136 */ "NullRow" OpHelp(""),
*/
static int winTruncate(sqlite3_file *id, sqlite3_int64 nByte){
winFile *pFile = (winFile*)id; /* File handle object */
int rc = SQLITE_OK; /* Return code for this function */
DWORD lastErrno;
#if SQLITE_MAX_MMAP_SIZE>0
sqlite3_int64 oldMmapSize;
if( pFile->nFetchOut>0 ){
/* File truncation is a no-op if there are outstanding memory mapped
** pages. This is because truncating the file means temporarily unmapping
** the file, and that might delete memory out from under existing cursors.
**
** This can result in incremental vacuum not truncating the file,
** if there is an active read cursor when the incremental vacuum occurs.
** No real harm comes of this - the database file is not corrupted,
** though some folks might complain that the file is bigger than it
** needs to be.
**
** The only feasible work-around is to defer the truncation until after
** all references to memory-mapped content are closed. That is doable,
** but involves adding a few branches in the common write code path which
** could slow down normal operations slightly. Hence, we have decided for
** now to simply make transactions a no-op if there are pending reads. We
** can maybe revisit this decision in the future.
** corruption-induced buffer overflow. */
u8 *aCellIdx; /* The cell index area */
u8 *aDataOfst; /* Same as aData for leaves. aData+4 for interior */
DbPage *pDbPage; /* Pager page handle */
u16 (*xCellSize)(MemPage*,u8*); /* cellSizePtr method */
void (*xParseCell)(MemPage*,u8*,CellInfo*); /* btreeParseCell method */
};
/*
** 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 */
};
** this structure.
**
** For some database files, the same underlying database cache might be
** shared between multiple connections. In that case, each connection
** has it own instance of 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 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 */
u8 hasIncrblobCur; /* True if there are one or more Incrblob cursors */
int wantToLock; /* Number of nested calls to sqlite3BtreeEnter() */
int nBackup; /* Number of backup operations reading this btree */
u32 iBDataVersion; /* Combines with pBt->pPager->iDataVersion */
Btree *pNext; /* List of other sharable Btrees from the same db */
Btree *pPrev; /* Back pointer of the same list */
#ifdef SQLITE_DEBUG
u64 nSeek; /* Calls to sqlite3BtreeMovetoUnpacked() */
#endif
#ifndef SQLITE_OMIT_SHARED_CACHE
BtLock lock; /* Object used to lock page 1 */
** 2) The number of locks held by other connections drops to zero.
**
** while in the 'pending-lock' state, no connection may start a new
** transaction.
**
** This feature is included to help prevent writer-starvation.
*/
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 openFlags; /* Flags to sqlite3BtreeOpen() */
#ifndef SQLITE_OMIT_AUTOVACUUM
u8 autoVacuum; /* True if auto-vacuum is enabled */
u8 incrVacuum; /* True if incr-vacuum is enabled */
u8 bDoTruncate; /* True to truncate db on commit */
#endif
u8 inTransaction; /* Transaction state */
u8 max1bytePayload; /* Maximum first byte of cell for a 1-byte payload */
u8 nReserveWanted; /* Desired number of extra bytes per page */
** this will be declared corrupt. This value is calculated based on a
** maximum database size of 2^31 pages a minimum fanout of 2 for a
** root-node and 3 for all other internal nodes.
**
** If a tree that appears to be taller than this is encountered, it is
** assumed that the database is corrupt.
*/
#define BTCURSOR_MAX_DEPTH 20
/*
** 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.
**
** A single database file can be 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.
**
** skipNext meaning:
** The meaning of skipNext depends on the value of eState:
**
** eState Meaning of skipNext
** VALID skipNext is meaningless and is ignored
** INVALID skipNext is meaningless and is ignored
** SKIPNEXT sqlite3BtreeNext() is a no-op if skipNext>0 and
** sqlite3BtreePrevious() is no-op if skipNext<0.
** REQUIRESEEK restoreCursorPosition() restores the cursor to
** eState=SKIPNEXT if skipNext!=0
** FAULT skipNext holds the cursor fault error code.
*/
struct BtCursor {
u8 eState; /* One of the CURSOR_XXX constants (see below) */
u8 curFlags; /* zero or more BTCF_* flags defined below */
u8 curPagerFlags; /* Flags to send to sqlite3PagerGet() */
u8 hints; /* As configured by CursorSetHints() */
int skipNext; /* Prev() is noop if negative. Next() is noop if positive.
** Error code if eState==CURSOR_FAULT */
Btree *pBtree; /* The Btree to which this cursor belongs */
Pgno *aOverflow; /* Cache of overflow page locations */
void *pKey; /* Saved key that was cursor last known position */
/* All fields above are zeroed when the cursor is allocated. See
** sqlite3BtreeCursorZero(). Fields that follow must be manually
** initialized. */
#define BTCURSOR_FIRST_UNINIT pBt /* Name of first uninitialized field */
BtShared *pBt; /* The BtShared this cursor points to */
BtCursor *pNext; /* Forms a linked list of all cursors */
CellInfo info; /* A parse of the cell we are pointing at */
i64 nKey; /* Size of pKey, or last integer key */
Pgno pgnoRoot; /* The root page of this tree */
i8 iPage; /* Index of current page in apPage */
u8 curIntKey; /* Value of apPage[0]->intKey */
u16 ix; /* Current index for apPage[iPage] */
u16 aiIdx[BTCURSOR_MAX_DEPTH-1]; /* Current index in apPage[i] */
struct KeyInfo *pKeyInfo; /* Arg passed to comparison function */
MemPage *pPage; /* Current page */
MemPage *apPage[BTCURSOR_MAX_DEPTH-1]; /* Stack of parents of current page */
};
/*
** Legal values for BtCursor.curFlags
*/
#define BTCF_WriteFlag 0x01 /* True if a write cursor */
#define BTCF_ValidNKey 0x02 /* True if info.nKey is valid */
#define BTCF_ValidOvfl 0x04 /* True if aOverflow is valid */
#define BTCF_AtLast 0x08 /* Cursor is pointing to the last entry */
#define BTCF_Incrblob 0x10 /* True if an incremental I/O handle */
#define BTCF_Multiple 0x20 /* Maybe another cursor on the same btree */
#define BTCF_Pinned 0x40 /* Cursor is busy and cannot be moved */
/*
** Potential values for BtCursor.eState.
**
** 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_VALID:
** Cursor points to a valid entry. getPayload() etc. may be called.
**
** CURSOR_SKIPNEXT:
** Cursor is valid except that the Cursor.skipNext field is non-zero
** indicating that the next sqlite3BtreeNext() or sqlite3BtreePrevious()
** operation should be a no-op.
**
** 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:
** An 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.skipNext
*/
#define CURSOR_VALID 0
#define CURSOR_INVALID 1
#define CURSOR_SKIPNEXT 2
#define CURSOR_REQUIRESEEK 3
#define CURSOR_FAULT 4
/*
** The database page the PENDING_BYTE occupies. This page is never used.
Btree *p = db->aDb[i].pBt;
if( p ){
p->pBt->db = p->db;
}
}
}
#endif /* if SQLITE_THREADSAFE */
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Enter a mutex on a Btree given a cursor owned by that Btree.
**
** These entry points are used by incremental I/O only. Enter() is required
** any time OMIT_SHARED_CACHE is not defined, regardless of whether or not
** the build is threadsafe. Leave() is only required by threadsafe builds.
*/
SQLITE_PRIVATE void sqlite3BtreeEnterCursor(BtCursor *pCur){
sqlite3BtreeEnter(pCur->pBtree);
}
# if SQLITE_THREADSAFE
SQLITE_PRIVATE void sqlite3BtreeLeaveCursor(BtCursor *pCur){
**** This function may be used as part of assert() statements only. ****
**
** Return true if it would be illegal for pBtree to write into the
** table or index rooted at iRoot because other shared connections are
** simultaneously reading that same table or index.
**
** It is illegal for pBtree to write if some other Btree object that
** shares the same BtShared object is currently reading or writing
** the iRoot table. Except, if the other Btree object has the
** read-uncommitted flag set, then it is OK for the other object to
** have a read cursor.
**
** For example, before writing to any part of the table or index
** rooted at page iRoot, one should call:
**
** assert( !hasReadConflicts(pBtree, iRoot) );
*/
static int hasReadConflicts(Btree *pBtree, Pgno iRoot){
BtCursor *p;
for(p=pBtree->pBt->pCursor; p; p=p->pNext){
if( p->pgnoRoot==iRoot
#endif /* SQLITE_OMIT_SHARED_CACHE */
static void releasePage(MemPage *pPage); /* Forward reference */
static void releasePageOne(MemPage *pPage); /* Forward reference */
static void releasePageNotNull(MemPage *pPage); /* Forward reference */
/*
***** This routine is used inside of assert() only ****
**
** Verify that the cursor holds the mutex on its BtShared
*/
#ifdef SQLITE_DEBUG
static int cursorHoldsMutex(BtCursor *p){
return sqlite3_mutex_held(p->pBt->mutex);
}
/* Verify that the cursor and the BtShared agree about what is the current
** database connetion. This is important in shared-cache mode. If the database
** connection pointers get out-of-sync, it is possible for routines like
** btreeInitPage() to reference an stale connection pointer that references a
** a connection that has already closed. This routine is used inside assert()
** statements only and for the purpose of double-checking that the btree code
** does keep the database connection pointers up-to-date.
*/
static int cursorOwnsBtShared(BtCursor *p){
assert( cursorHoldsMutex(p) );
return (p->pBtree->db==p->pBt->db);
}
#endif
/*
** Invalidate the overflow cache of the cursor passed as the first argument.
** on the shared btree structure pBt.
*/
#define invalidateOverflowCache(pCur) (pCur->curFlags &= ~BTCF_ValidOvfl)
/*
** 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);
}
}
#ifndef SQLITE_OMIT_INCRBLOB
/*
** This function is called before modifying the contents of a table
** to invalidate any incrblob cursors that are open on the
** row or one of the rows being modified.
**
** If argument isClearTable is true, then the entire contents of the
** table is about to be deleted. In this case invalidate all incrblob
** cursors open on any row within the table with root-page pgnoRoot.
**
** Otherwise, if argument isClearTable is false, then the row with
** rowid iRow is being replaced or deleted. In this case invalidate
** only those incrblob cursors open on that specific row.
*/
static void invalidateIncrblobCursors(
Btree *pBtree, /* The database file to check */
Pgno pgnoRoot, /* The table that might be changing */
i64 iRow, /* The rowid that might be changing */
int isClearTable /* True if all rows are being deleted */
){
BtCursor *p;
assert( pBtree->hasIncrblobCur );
assert( sqlite3BtreeHoldsMutex(pBtree) );
/*
** Clear (destroy) the BtShared.pHasContent bitvec. This should be
** invoked at the conclusion of each write-transaction.
*/
static void btreeClearHasContent(BtShared *pBt){
sqlite3BitvecDestroy(pBt->pHasContent);
pBt->pHasContent = 0;
}
/*
** Release all of the apPage[] pages for a cursor.
*/
static void btreeReleaseAllCursorPages(BtCursor *pCur){
int i;
if( pCur->iPage>=0 ){
for(i=0; i<pCur->iPage; i++){
releasePageNotNull(pCur->apPage[i]);
}
releasePageNotNull(pCur->pPage);
pCur->iPage = -1;
}
}
/*
** The cursor passed as the only argument must point to a valid entry
** when this function is called (i.e. have eState==CURSOR_VALID). This
** function saves the current cursor key in variables pCur->nKey and
** pCur->pKey. SQLITE_OK is returned if successful or an SQLite error
** code otherwise.
**
** If the cursor is open on an intkey table, then the integer key
** (the rowid) is stored in pCur->nKey and pCur->pKey is left set to
** NULL. If the cursor is open on a non-intkey table, then pCur->pKey is
** set to point to a malloced buffer pCur->nKey bytes in size containing
** the key.
*/
static int saveCursorKey(BtCursor *pCur){
int rc = SQLITE_OK;
assert( CURSOR_VALID==pCur->eState );
assert( 0==pCur->pKey );
assert( cursorHoldsMutex(pCur) );
if( pCur->curIntKey ){
/* Only the rowid is required for a table btree */
pCur->nKey = sqlite3BtreeIntegerKey(pCur);
}else{
/* For an index btree, save the complete key content. It is possible
** that the current key is corrupt. In that case, it is possible that
** the sqlite3VdbeRecordUnpack() function may overread the buffer by
** up to the size of 1 varint plus 1 8-byte value when the cursor
** position is restored. Hence the 17 bytes of padding allocated
** below. */
void *pKey;
pCur->nKey = sqlite3BtreePayloadSize(pCur);
pKey = sqlite3Malloc( pCur->nKey + 9 + 8 );
if( pKey ){
rc = sqlite3BtreePayload(pCur, 0, (int)pCur->nKey, pKey);
if( rc==SQLITE_OK ){
memset(((u8*)pKey)+pCur->nKey, 0, 9+8);
pCur->pKey = pKey;
}
}else{
rc = SQLITE_NOMEM_BKPT;
}
}
assert( !pCur->curIntKey || !pCur->pKey );
return rc;
}
/*
** Save the current cursor position in the variables BtCursor.nKey
** and BtCursor.pKey. The cursor's state is set to CURSOR_REQUIRESEEK.
**
** The caller must ensure that the cursor is valid (has eState==CURSOR_VALID)
** prior to calling this routine.
*/
static int saveCursorPosition(BtCursor *pCur){
int rc;
assert( CURSOR_VALID==pCur->eState || CURSOR_SKIPNEXT==pCur->eState );
assert( 0==pCur->pKey );
assert( cursorHoldsMutex(pCur) );
if( pCur->curFlags & BTCF_Pinned ){
return SQLITE_CONSTRAINT_PINNED;
}
if( pCur->eState==CURSOR_SKIPNEXT ){
pCur->eState = CURSOR_VALID;
}else{
pCur->skipNext = 0;
}
}
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl|BTCF_AtLast);
return rc;
}
/* Forward reference */
static int SQLITE_NOINLINE saveCursorsOnList(BtCursor*,Pgno,BtCursor*);
/*
** Save the positions of all cursors (except pExcept) that are open on
** the table with root-page iRoot. "Saving the cursor position" means that
** the location in the btree is remembered in such a way that it can be
** moved back to the same spot after the btree has been modified. This
** routine is called just before cursor pExcept is used to modify the
** table, for example in BtreeDelete() or BtreeInsert().
**
** If there are two or more cursors on the same btree, then all such
** cursors should have their BTCF_Multiple flag set. The btreeCursor()
** routine enforces that rule. This routine only needs to be called in
** the uncommon case when pExpect has the BTCF_Multiple flag set.
**
** If pExpect!=NULL and if no other cursors are found on the same root-page,
** then the BTCF_Multiple flag on pExpect is cleared, to avoid another
** pointless call to this routine.
**
** Implementation note: This routine merely checks to see if any cursors
** need to be saved. It calls out to saveCursorsOnList() in the (unusual)
** event that cursors are in need to being saved.
*/
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) ) break;
}
if( p ) return saveCursorsOnList(p, iRoot, pExcept);
if( pExcept ) pExcept->curFlags &= ~BTCF_Multiple;
return SQLITE_OK;
}
/* This helper routine to saveAllCursors does the actual work of saving
** the cursors if and when a cursor is found that actually requires saving.
** The common case is that no cursors need to be saved, so this routine is
** broken out from its caller to avoid unnecessary stack pointer movement.
*/
static int SQLITE_NOINLINE saveCursorsOnList(
BtCursor *p, /* The first cursor that needs saving */
Pgno iRoot, /* Only save cursor with this iRoot. Save all if zero */
BtCursor *pExcept /* Do not save this cursor */
){
do{
if( p!=pExcept && (0==iRoot || p->pgnoRoot==iRoot) ){
if( p->eState==CURSOR_VALID || p->eState==CURSOR_SKIPNEXT ){
int rc = saveCursorPosition(p);
if( SQLITE_OK!=rc ){
return rc;
}
}else{
testcase( p->iPage>=0 );
btreeReleaseAllCursorPages(p);
}
}
p = p->pNext;
}while( p );
return SQLITE_OK;
}
/*
** Clear the current cursor position.
*/
SQLITE_PRIVATE void sqlite3BtreeClearCursor(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
sqlite3_free(pCur->pKey);
pCur->pKey = 0;
pCur->eState = CURSOR_INVALID;
}
/*
** In this version of BtreeMoveto, pKey is a packed index record
** such as is generated by the OP_MakeRecord opcode. Unpack the
** record and then call sqlite3BtreeIndexMoveto() to do the work.
*/
}
sqlite3DbFree(pCur->pKeyInfo->db, pIdxKey);
}else{
pIdxKey = 0;
rc = sqlite3BtreeTableMoveto(pCur, nKey, bias, pRes);
}
return rc;
}
/*
** 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().
*/
static int btreeRestoreCursorPosition(BtCursor *pCur){
int rc;
int skipNext = 0;
assert( cursorOwnsBtShared(pCur) );
assert( pCur->eState>=CURSOR_REQUIRESEEK );
if( pCur->eState==CURSOR_FAULT ){
return pCur->skipNext;
}
pCur->eState = CURSOR_INVALID;
if( sqlite3FaultSim(410) ){
rc = SQLITE_IOERR;
}else{
rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &skipNext);
}
}
return rc;
}
#define restoreCursorPosition(p) \
(p->eState>=CURSOR_REQUIRESEEK ? \
btreeRestoreCursorPosition(p) : \
SQLITE_OK)
/*
** Determine whether or not a cursor has moved from the position where
** it was last placed, or has been invalidated for any other reason.
** Cursors can move when the row they are pointing at is deleted out
** from under them, for example. Cursor might also move if a btree
** is rebalanced.
**
** Calling this routine with a NULL cursor pointer returns false.
**
** Use the separate sqlite3BtreeCursorRestore() routine to restore a cursor
** back to where it ought to be if this routine returns true.
*/
SQLITE_PRIVATE int sqlite3BtreeCursorHasMoved(BtCursor *pCur){
assert( EIGHT_BYTE_ALIGNMENT(pCur)
|| pCur==sqlite3BtreeFakeValidCursor() );
assert( offsetof(BtCursor, eState)==0 );
assert( sizeof(pCur->eState)==1 );
return CURSOR_VALID != *(u8*)pCur;
}
/*
** Return a pointer to a fake BtCursor object that will always answer
** false to the sqlite3BtreeCursorHasMoved() routine above. The fake
** cursor returned must not be used with any other Btree interface.
*/
SQLITE_PRIVATE BtCursor *sqlite3BtreeFakeValidCursor(void){
static u8 fakeCursor = CURSOR_VALID;
assert( offsetof(BtCursor, eState)==0 );
return (BtCursor*)&fakeCursor;
}
/*
** This routine restores a cursor back to its original position after it
** has been moved by some outside activity (such as a btree rebalance or
** a row having been deleted out from under the cursor).
**
** On success, the *pDifferentRow parameter is false if the cursor is left
** pointing at exactly the same row. *pDifferntRow is the row the cursor
** was pointing to has been deleted, forcing the cursor to point to some
** nearby row.
**
** This routine should only be called for a cursor that just returned
** TRUE from sqlite3BtreeCursorHasMoved().
*/
SQLITE_PRIVATE int sqlite3BtreeCursorRestore(BtCursor *pCur, int *pDifferentRow){
int rc;
assert( pCur!=0 );
assert( pCur->eState!=CURSOR_VALID );
rc = restoreCursorPosition(pCur);
if( rc ){
*pDifferentRow = 1;
if( pCur->eState!=CURSOR_VALID ){
*pDifferentRow = 1;
}else{
*pDifferentRow = 0;
}
return SQLITE_OK;
}
#ifdef SQLITE_ENABLE_CURSOR_HINTS
/*
** Provide hints to the cursor. The particular hint given (and the type
** and number of the varargs parameters) is determined by the eHintType
** parameter. See the definitions of the BTREE_HINT_* macros for details.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorHint(BtCursor *pCur, int eHintType, ...){
/* Used only by system that substitute their own storage engine */
#ifdef SQLITE_DEBUG
if( ALWAYS(eHintType==BTREE_HINT_RANGE) ){
va_list ap;
Expr *pExpr;
Walker w;
assert( pExpr!=0 );
assert( w.u.aMem!=0 );
sqlite3WalkExpr(&w, pExpr);
}
#endif /* SQLITE_DEBUG */
}
#endif /* SQLITE_ENABLE_CURSOR_HINTS */
/*
** Provide flag hints to the cursor.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorHintFlags(BtCursor *pCur, unsigned x){
assert( x==BTREE_SEEK_EQ || x==BTREE_BULKLOAD || x==0 );
pCur->hints = x;
}
#ifndef SQLITE_OMIT_AUTOVACUUM
/*
** Given a page number of a regular database page, return the page
/*
** Make sure pBt->pTmpSpace points to an allocation of
** MX_CELL_SIZE(pBt) bytes with a 4-byte prefix for a left-child
** pointer.
*/
static SQLITE_NOINLINE int allocateTempSpace(BtShared *pBt){
assert( pBt!=0 );
assert( pBt->pTmpSpace==0 );
/* This routine is called only by btreeCursor() when allocating the
** first write cursor for the BtShared object */
assert( pBt->pCursor!=0 && (pBt->pCursor->curFlags & BTCF_WriteFlag)!=0 );
pBt->pTmpSpace = sqlite3PageMalloc( pBt->pageSize );
if( pBt->pTmpSpace==0 ){
BtCursor *pCur = pBt->pCursor;
pBt->pCursor = pCur->pNext; /* Unlink the cursor */
memset(pCur, 0, sizeof(*pCur));
return SQLITE_NOMEM_BKPT;
}
/* One of the uses of pBt->pTmpSpace is to format cells before
** inserting them into a leaf page (function fillInCell()). If
** a cell is less than 4 bytes in size, it is rounded up to 4 bytes
** by the various routines that manipulate binary cells. Which
** can mean that fillInCell() only initializes the first 2 or 3
** bytes of pTmpSpace, but that the first 4 bytes are copied from
*/
static void freeTempSpace(BtShared *pBt){
if( pBt->pTmpSpace ){
pBt->pTmpSpace -= 4;
sqlite3PageFree(pBt->pTmpSpace);
pBt->pTmpSpace = 0;
}
}
/*
** Close an open database and invalidate all cursors.
*/
SQLITE_PRIVATE int sqlite3BtreeClose(Btree *p){
BtShared *pBt = p->pBt;
/* Close all cursors opened via this handle. */
assert( sqlite3_mutex_held(p->db->mutex) );
sqlite3BtreeEnter(p);
/* Verify that no other cursors have this Btree open */
#ifdef SQLITE_DEBUG
{
BtCursor *pCur = pBt->pCursor;
while( pCur ){
BtCursor *pTmp = pCur;
pCur = pCur->pNext;
assert( pTmp->pBtree!=p );
}
}
return SQLITE_OK;
page1_init_failed:
releasePageOne(pPage1);
pBt->pPage1 = 0;
return rc;
}
#ifndef NDEBUG
/*
** Return the number of cursors open on pBt. This is for use
** in assert() expressions, so it is only compiled if NDEBUG is not
** defined.
**
** Only write cursors are counted if wrOnly is true. If wrOnly is
** false then all cursors are counted.
**
** For the purposes of this routine, a cursor is any cursor that
** is capable of reading or writing to the database. Cursors that
** have been tripped into the CURSOR_FAULT state are not counted.
*/
static int countValidCursors(BtShared *pBt, int wrOnly){
BtCursor *pCur;
int r = 0;
for(pCur=pBt->pCursor; pCur; pCur=pCur->pNext){
if( (wrOnly==0 || (pCur->curFlags & BTCF_WriteFlag)!=0)
&& pCur->eState!=CURSOR_FAULT ) r++;
}
return r;
}
#endif
/*
** 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 is a transaction in progress, this routine is a no-op.
*/
static void unlockBtreeIfUnused(BtShared *pBt){
assert( sqlite3_mutex_held(pBt->mutex) );
assert( countValidCursors(pBt,0)==0 || pBt->inTransaction>TRANS_NONE );
if( pBt->inTransaction==TRANS_NONE && pBt->pPage1!=0 ){
** the upper layer will attempt a rollback. However, if the second argument
** is non-zero then this b-tree transaction is part of a multi-file
** transaction. In this case, the transaction has already been committed
** (by deleting a super-journal file) and the caller will ignore this
** functions return code. So, even if an error occurs in the pager layer,
** reset the b-tree objects internal state to indicate that the write
** transaction has been closed. This is quite safe, as the pager will have
** transitioned to the error state.
**
** 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, int bCleanup){
if( p->inTrans==TRANS_NONE ) return SQLITE_OK;
sqlite3BtreeEnter(p);
btreeIntegrity(p);
/* If the handle has a write-transaction open, commit the shared-btrees
** transaction and set the shared state to TRANS_READ.
*/
rc = sqlite3BtreeCommitPhaseOne(p, 0);
if( rc==SQLITE_OK ){
rc = sqlite3BtreeCommitPhaseTwo(p, 0);
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** This routine sets the state to CURSOR_FAULT and the error
** code to errCode for every cursor on any BtShared that pBtree
** references. Or if the writeOnly flag is set to 1, then only
** trip write cursors and leave read cursors unchanged.
**
** Every cursor is a candidate to be 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. If the writeOnly
** flag is true, then only write-cursors need be tripped - read-only
** cursors save their current positions so that they may continue
** following the rollback. Or, if writeOnly is false, all cursors are
** tripped. In general, writeOnly is false if the transaction being
** rolled back modified the database schema. In this case b-tree root
** pages may be moved or deleted from the database altogether, making
** it unsafe for read cursors to continue.
**
** If the writeOnly flag is true and an error is encountered while
** saving the current position of a read-only cursor, all cursors,
** including all read-cursors are tripped.
**
** SQLITE_OK is returned if successful, or if an error occurs while
** saving a cursor position, an SQLite error code.
*/
SQLITE_PRIVATE int sqlite3BtreeTripAllCursors(Btree *pBtree, int errCode, int writeOnly){
BtCursor *p;
int rc = SQLITE_OK;
assert( (writeOnly==0 || writeOnly==1) && BTCF_WriteFlag==1 );
if( pBtree ){
sqlite3BtreeEnter(pBtree);
for(p=pBtree->pBt->pCursor; p; p=p->pNext){
if( writeOnly && (p->curFlags & BTCF_WriteFlag)==0 ){
int nPage = get4byte(&pPage1->aData[28]);
testcase( nPage==0 );
if( nPage==0 ) sqlite3PagerPagecount(pBt->pPager, &nPage);
testcase( pBt->nPage!=(u32)nPage );
pBt->nPage = nPage;
}
/*
** Rollback the transaction in progress.
**
** If tripCode is not SQLITE_OK then cursors will be invalidated (tripped).
** Only write cursors are tripped if writeOnly is true but all cursors are
** tripped if writeOnly is false. Any attempt to use
** a tripped cursor 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 tripCode, int writeOnly){
int rc;
BtShared *pBt = p->pBt;
MemPage *pPage1;
assert( writeOnly==1 || writeOnly==0 );
assert( tripCode==SQLITE_ABORT_ROLLBACK || tripCode==SQLITE_OK );
sqlite3BtreeEnter(p);
if( tripCode==SQLITE_OK ){
/* pBt->nPage might be zero if the database was corrupt when
** the transaction was started. Otherwise, it must be at least 1. */
assert( CORRUPT_DB || pBt->nPage>0 );
}
sqlite3BtreeLeave(p);
}
return rc;
}
/*
** Create a new cursor for the BTree whose root is on the page
** iTable. If a read-only cursor is requested, it is assumed that
** the caller already has at least a read-only transaction open
** on the database already. If a write-cursor is requested, then
** the caller is assumed to have an open write transaction.
**
** If the BTREE_WRCSR bit of wrFlag is clear, then the cursor can only
** be used for reading. If the BTREE_WRCSR bit is set, 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 containing BTREE_WRCSR
**
** 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.
**
** The BTREE_FORDELETE bit of wrFlag may optionally be set if BTREE_WRCSR
** is set. If FORDELETE is set, that is a hint to the implementation that
** this cursor will only be used to seek to and delete entries of an index
** as part of a larger DELETE statement. The FORDELETE hint is not used by
** this implementation. But in a hypothetical alternative storage engine
** in which index entries are automatically deleted when corresponding table
** rows are deleted, the FORDELETE flag is a hint that all SEEK and DELETE
** operations on this cursor can be no-ops and all READ operations can
** return a null row (2-bytes: 0x01 0x00).
**
** 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.
**
** It is assumed that the sqlite3BtreeCursorZero() has been called
** on pCur to initialize the memory space prior to invoking this routine.
*/
static int btreeCursor(
Btree *p, /* The btree */
Pgno 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 */
){
BtShared *pBt = p->pBt; /* Shared b-tree handle */
BtCursor *pX; /* Looping over other all cursors */
assert( sqlite3BtreeHoldsMutex(p) );
assert( wrFlag==0
|| wrFlag==BTREE_WRCSR
|| wrFlag==(BTREE_WRCSR|BTREE_FORDELETE)
);
/* The following assert statements verify that if this is a sharable
** b-tree database, the connection is holding the required table locks,
** and that no other connection has any open cursor that conflicts with
** this lock. The iTable<1 term disables the check for corrupt schemas. */
assert( hasSharedCacheTableLock(p, iTable, pKeyInfo!=0, (wrFlag?2:1))
|| iTable<1 );
assert( wrFlag==0 || !hasReadConflicts(p, iTable) );
/* Assert that the caller has opened the required transaction. */
assert( p->inTrans>TRANS_NONE );
assert( wrFlag==0 || p->inTrans==TRANS_WRITE );
assert( pBt->pPage1 && pBt->pPage1->aData );
assert( wrFlag==0 || (pBt->btsFlags & BTS_READ_ONLY)==0 );
if( iTable<=1 ){
if( iTable<1 ){
return SQLITE_CORRUPT_BKPT;
}else if( btreePagecount(pBt)==0 ){
assert( wrFlag==0 );
iTable = 0;
}
}
/* Now that no other errors can occur, finish filling in the BtCursor
** variables and link the cursor into the BtShared list. */
pCur->pgnoRoot = iTable;
pCur->iPage = -1;
pCur->pKeyInfo = pKeyInfo;
pCur->pBtree = p;
pCur->pBt = pBt;
pCur->curFlags = 0;
/* If there are two or more cursors on the same btree, then all such
** cursors *must* have the BTCF_Multiple flag set. */
for(pX=pBt->pCursor; pX; pX=pX->pNext){
if( pX->pgnoRoot==iTable ){
pX->curFlags |= BTCF_Multiple;
pCur->curFlags = BTCF_Multiple;
}
}
pCur->eState = CURSOR_INVALID;
pCur->pNext = pBt->pCursor;
pBt->pCursor = pCur;
if( wrFlag ){
}else{
pCur->curPagerFlags = PAGER_GET_READONLY;
}
return SQLITE_OK;
}
static int btreeCursorWithLock(
Btree *p, /* The btree */
Pgno 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;
sqlite3BtreeEnter(p);
rc = btreeCursor(p, iTable, wrFlag, pKeyInfo, pCur);
sqlite3BtreeLeave(p);
return rc;
}
SQLITE_PRIVATE int sqlite3BtreeCursor(
Btree *p, /* The btree */
Pgno 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 */
){
if( p->sharable ){
return btreeCursorWithLock(p, iTable, wrFlag, pKeyInfo, pCur);
}else{
return btreeCursor(p, iTable, wrFlag, pKeyInfo, pCur);
}
}
/*
** Return the size of a BtCursor object in bytes.
**
** This interfaces is needed so that users of cursors can preallocate
** sufficient storage to hold a cursor. The BtCursor object is opaque
** to users so they cannot do the sizeof() themselves - they must call
** this routine.
*/
SQLITE_PRIVATE int sqlite3BtreeCursorSize(void){
return ROUND8(sizeof(BtCursor));
}
/*
** Initialize memory that will be converted into a BtCursor object.
**
** The simple approach here would be to memset() the entire object
** to zero. But it turns out that the apPage[] and aiIdx[] arrays
** do not need to be zeroed and they are large, so we can save a lot
** of run-time by skipping the initialization of those elements.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorZero(BtCursor *p){
memset(p, 0, offsetof(BtCursor, BTCURSOR_FIRST_UNINIT));
}
/*
** 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);
assert( pBt->pCursor!=0 );
if( pBt->pCursor==pCur ){
pBt->pCursor = pCur->pNext;
}else{
if( pCur->info.nSize==0 ){
pCur->curFlags |= BTCF_ValidNKey;
btreeParseCell(pCur->pPage,pCur->ix,&pCur->info);
}else{
assertCellInfo(pCur);
}
}
#ifndef NDEBUG /* The next routine used only within assert() statements */
/*
** Return true if the given BtCursor is valid. A valid cursor is one
** that is currently pointing to a row in a (non-empty) table.
** This is a verification routine is used only within assert() statements.
*/
SQLITE_PRIVATE int sqlite3BtreeCursorIsValid(BtCursor *pCur){
return pCur && pCur->eState==CURSOR_VALID;
}
#endif /* NDEBUG */
SQLITE_PRIVATE int sqlite3BtreeCursorIsValidNN(BtCursor *pCur){
assert( pCur!=0 );
return pCur->eState==CURSOR_VALID;
}
/*
** Return the value of the integer key or "rowid" for a table btree.
** This routine is only valid for a cursor that is pointing into a
** ordinary table btree. If the cursor points to an index btree or
** is invalid, the result of this routine is undefined.
*/
SQLITE_PRIVATE i64 sqlite3BtreeIntegerKey(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->curIntKey );
getCellInfo(pCur);
return pCur->info.nKey;
}
/*
** Pin or unpin a cursor.
*/
SQLITE_PRIVATE void sqlite3BtreeCursorPin(BtCursor *pCur){
assert( (pCur->curFlags & BTCF_Pinned)==0 );
pCur->curFlags |= BTCF_Pinned;
}
SQLITE_PRIVATE void sqlite3BtreeCursorUnpin(BtCursor *pCur){
assert( (pCur->curFlags & BTCF_Pinned)!=0 );
pCur->curFlags &= ~BTCF_Pinned;
}
/*
** Return the offset into the database file for the start of the
** payload to which the cursor is pointing.
*/
SQLITE_PRIVATE i64 sqlite3BtreeOffset(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
getCellInfo(pCur);
return (i64)pCur->pBt->pageSize*((i64)pCur->pPage->pgno - 1) +
(i64)(pCur->info.pPayload - pCur->pPage->aData);
}
/*
** Return the number of bytes of payload for the entry that pCur is
** currently pointing to. For table btrees, this will be the amount
** of data. For index btrees, this will be the size of the key.
**
** The caller must guarantee that the cursor is pointing to a non-NULL
** valid entry. In other words, the calling procedure must guarantee
** that the cursor has Cursor.eState==CURSOR_VALID.
*/
SQLITE_PRIVATE u32 sqlite3BtreePayloadSize(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
getCellInfo(pCur);
return pCur->info.nPayload;
}
/*
** Return an upper bound on the size of any record for the table
** that the cursor is pointing into.
**
** This is an optimization. Everything will still work if this
** routine always returns 2147483647 (which is the largest record
** that SQLite can handle) or more. But returning a smaller value might
** prevent large memory allocations when trying to interpret a
** corrupt database.
**
** The current implementation merely returns the size of the underlying
** database file.
*/
SQLITE_PRIVATE sqlite3_int64 sqlite3BtreeMaxRecordSize(BtCursor *pCur){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
return pCur->pBt->pageSize * (sqlite3_int64)pCur->pBt->nPage;
}
/*
** 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.
**
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. The eOp
** argument is interpreted as follows:
**
** 0: The operation is a read. Populate the overflow cache.
** 1: The operation is a write. Populate the overflow cache.
**
** A total of "amt" bytes are read or written beginning at "offset".
** Data is read to or from the buffer pBuf.
**
** The content being read or written might appear on the main page
** or be scattered out on multiple overflow pages.
**
** If the current cursor entry uses one or more overflow pages
** this function may allocate space for and lazily populate
** 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 must 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 */
u32 offset, /* Begin reading this far into payload */
u32 amt, /* Read this many bytes */
unsigned char *pBuf, /* Write the bytes into this buffer */
int eOp /* zero to read. non-zero to write. */
){
unsigned char *aPayload;
int rc = SQLITE_OK;
int iIdx = 0;
MemPage *pPage = pCur->pPage; /* Btree page of current entry */
BtShared *pBt = pCur->pBt; /* Btree this cursor belongs to */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
unsigned char * const pBufStart = pBuf; /* Start of original out buffer */
#endif
assert( pPage );
assert( eOp==0 || eOp==1 );
assert( pCur->eState==CURSOR_VALID );
if( pCur->ix>=pPage->nCell ){
return SQLITE_CORRUPT_PAGE(pPage);
}
assert( cursorHoldsMutex(pCur) );
getCellInfo(pCur);
aPayload = pCur->info.pPayload;
assert( offset+amt <= pCur->info.nPayload );
assert( aPayload > pPage->aData );
if( (uptr)(aPayload - pPage->aData) > (pBt->usableSize - pCur->info.nLocal) ){
/* Trying to read or write past the end of the data is an error. The
** conditional above is really:
** &aPayload[pCur->info.nLocal] > &pPage->aData[pBt->usableSize]
}
if( rc==SQLITE_OK && amt>0 ){
/* Overflow chain ends prematurely */
return SQLITE_CORRUPT_PAGE(pPage);
}
return rc;
}
/*
** Read part of the payload for the row at which that cursor pCur is currently
** pointing. "amt" bytes will be transferred into pBuf[]. The transfer
** begins at "offset".
**
** pCur can be pointing to either a table or an index b-tree.
** If pointing to a table btree, then the content section is read. If
** pCur is pointing to an index b-tree then the key section is read.
**
** For sqlite3BtreePayload(), the caller must ensure that pCur is pointing
** to a valid row in the table. For sqlite3BtreePayloadChecked(), the
** cursor might be invalid or might need to be restored before being read.
**
** 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 sqlite3BtreePayload(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage>=0 && pCur->pPage );
return accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0);
}
/*
** This variant of sqlite3BtreePayload() works even if the cursor has not
** in the CURSOR_VALID state. It is only used by the sqlite3_blob_read()
** interface.
*/
#ifndef SQLITE_OMIT_INCRBLOB
static SQLITE_NOINLINE int accessPayloadChecked(
BtCursor *pCur,
u32 offset,
u32 amt,
void *pBuf
){
int rc;
if ( pCur->eState==CURSOR_INVALID ){
return SQLITE_ABORT;
}
assert( cursorOwnsBtShared(pCur) );
rc = btreeRestoreCursorPosition(pCur);
return rc ? rc : accessPayload(pCur, offset, amt, pBuf, 0);
}
SQLITE_PRIVATE int sqlite3BtreePayloadChecked(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
if( pCur->eState==CURSOR_VALID ){
assert( cursorOwnsBtShared(pCur) );
return accessPayload(pCur, offset, amt, pBuf, 0);
}else{
return accessPayloadChecked(pCur, offset, amt, pBuf);
}
}
#endif /* SQLITE_OMIT_INCRBLOB */
/*
** 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 index btrees (pPage->intKey==0) and is the data for
** table btrees (pPage->intKey==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 reassemble
** any btree routine is called.
*/
static const void *fetchPayload(
BtCursor *pCur, /* Cursor pointing to entry to read from */
u32 *pAmt /* Write the number of available bytes here */
){
int amt;
assert( pCur!=0 && pCur->iPage>=0 && pCur->pPage);
assert( pCur->eState==CURSOR_VALID );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert( cursorOwnsBtShared(pCur) );
assert( pCur->ix<pCur->pPage->nCell || CORRUPT_DB );
assert( pCur->info.nSize>0 );
assert( pCur->info.pPayload>pCur->pPage->aData || CORRUPT_DB );
assert( pCur->info.pPayload<pCur->pPage->aDataEnd ||CORRUPT_DB);
amt = pCur->info.nLocal;
if( amt>(int)(pCur->pPage->aDataEnd - pCur->info.pPayload) ){
/* There is too little space on the page for the expected amount
** of local content. Database must be corrupt. */
assert( CORRUPT_DB );
amt = MAX(0, (int)(pCur->pPage->aDataEnd - pCur->info.pPayload));
}
*pAmt = (u32)amt;
return (void*)pCur->info.pPayload;
}
/*
** 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 *sqlite3BtreePayloadFetch(BtCursor *pCur, u32 *pAmt){
return fetchPayload(pCur, pAmt);
}
/*
** Move the cursor down to a new child page. The newPgno argument is the
** page number of the child page to move to.
**
** This function returns SQLITE_CORRUPT if the page-header flags field of
** the new child page does not match the flags field of the parent (i.e.
** if an intkey page appears to be the parent of a non-intkey page, or
** vice-versa).
*/
static int moveToChild(BtCursor *pCur, u32 newPgno){
int rc;
assert( cursorOwnsBtShared(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
assert( pCur->iPage>=0 );
if( pCur->iPage>=(BTCURSOR_MAX_DEPTH-1) ){
return SQLITE_CORRUPT_BKPT;
}
pCur->info.nSize = 0;
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
pCur->aiIdx[pCur->iPage] = pCur->ix;
pCur->apPage[pCur->iPage] = pCur->pPage;
assert( get4byte(&pParent->aData[pParent->hdrOffset+8])==iChild );
}else{
assert( get4byte(findCell(pParent, iIdx))==iChild );
}
}
#else
# define assertParentIndex(x,y,z)
#endif
/*
** 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.
*/
static void moveToParent(BtCursor *pCur){
MemPage *pLeaf;
assert( cursorOwnsBtShared(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage>0 );
assert( pCur->pPage );
assertParentIndex(
pCur->apPage[pCur->iPage-1],
pCur->aiIdx[pCur->iPage-1],
pCur->pPage->pgno
);
testcase( pCur->aiIdx[pCur->iPage-1] > pCur->apPage[pCur->iPage-1]->nCell );
pCur->info.nSize = 0;
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
pCur->ix = pCur->aiIdx[pCur->iPage-1];
pLeaf = pCur->pPage;
pCur->pPage = pCur->apPage[--pCur->iPage];
releasePageNotNull(pLeaf);
}
/*
** Move the cursor to point to the root page of its b-tree structure.
**
** If the table has a virtual root page, then the cursor is moved to point
** to the virtual root page instead of the actual root page. A table has a
** virtual root page when the actual root page contains no cells and a
** single child page. This can only happen with the table rooted at page 1.
**
** If the b-tree structure is empty, the cursor state is set to
** CURSOR_INVALID and this routine returns SQLITE_EMPTY. Otherwise,
** the cursor is set to point to the first cell located on the root
** (or virtual root) page and the cursor state is set to CURSOR_VALID.
**
** If this function returns successfully, it may be assumed that the
** page-header flags indicate that the [virtual] root-page is the expected
** kind of b-tree page (i.e. if when opening the cursor the caller did not
** specify a KeyInfo structure the flags byte is set to 0x05 or 0x0D,
** indicating a table b-tree, or if the caller did specify a KeyInfo
** structure the flags byte is set to 0x02 or 0x0A, indicating an index
** b-tree).
*/
static int moveToRoot(BtCursor *pCur){
MemPage *pRoot;
int rc = SQLITE_OK;
assert( cursorOwnsBtShared(pCur) );
assert( CURSOR_INVALID < CURSOR_REQUIRESEEK );
assert( CURSOR_VALID < CURSOR_REQUIRESEEK );
assert( CURSOR_FAULT > CURSOR_REQUIRESEEK );
assert( pCur->eState < CURSOR_REQUIRESEEK || pCur->iPage<0 );
assert( pCur->pgnoRoot>0 || pCur->iPage<0 );
if( pCur->iPage>=0 ){
if( pCur->iPage ){
releasePageNotNull(pCur->pPage);
while( --pCur->iPage ){
if( rc!=SQLITE_OK ){
pCur->eState = CURSOR_INVALID;
return rc;
}
pCur->iPage = 0;
pCur->curIntKey = pCur->pPage->intKey;
}
pRoot = pCur->pPage;
assert( pRoot->pgno==pCur->pgnoRoot || CORRUPT_DB );
/* If pCur->pKeyInfo is not NULL, then the caller that opened this cursor
** expected to open it on an index b-tree. Otherwise, if pKeyInfo is
** NULL, the caller expects a table b-tree. If this is not the case,
** return an SQLITE_CORRUPT error.
**
** Earlier versions of SQLite assumed that this test could not fail
** if the root page was already loaded when this function was called (i.e.
** if pCur->iPage>=0). But this is not so if the database is corrupted
** in such a way that page pRoot is linked into a second b-tree table
** (or the freelist). */
assert( pRoot->intKey==1 || pRoot->intKey==0 );
pCur->eState = CURSOR_VALID;
rc = moveToChild(pCur, subpage);
}else{
pCur->eState = CURSOR_INVALID;
rc = SQLITE_EMPTY;
}
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( cursorOwnsBtShared(pCur) );
assert( pCur->eState==CURSOR_VALID );
while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
assert( pCur->ix<pPage->nCell );
pgno = get4byte(findCell(pPage, pCur->ix));
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 = 0;
assert( cursorOwnsBtShared(pCur) );
assert( pCur->eState==CURSOR_VALID );
while( !(pPage = pCur->pPage)->leaf ){
pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
pCur->ix = pPage->nCell;
rc = moveToChild(pCur, pgno);
if( rc ) return rc;
}
pCur->ix = pPage->nCell-1;
assert( pCur->info.nSize==0 );
assert( (pCur->curFlags & BTCF_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( cursorOwnsBtShared(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
rc = moveToRoot(pCur);
if( rc==SQLITE_OK ){
assert( pCur->pPage->nCell>0 );
*pRes = 0;
rc = moveToLeftmost(pCur);
}else if( rc==SQLITE_EMPTY ){
assert( pCur->pgnoRoot==0 || (pCur->pPage!=0 && pCur->pPage->nCell==0) );
*pRes = 1;
rc = SQLITE_OK;
}
return rc;
}
#ifdef SQLITE_DEBUG
/* The cursors is CURSOR_VALID and has BTCF_AtLast set. Verify that
** this flags are true for a consistent database.
**
** This routine is is called from within assert() statements only.
** It is an internal verification routine and does not appear in production
** builds.
*/
static int cursorIsAtLastEntry(BtCursor *pCur){
int ii;
for(ii=0; ii<pCur->iPage; ii++){
if( pCur->aiIdx[ii]!=pCur->apPage[ii]->nCell ) return 0;
}
return pCur->ix==pCur->pPage->nCell-1 && pCur->pPage->leaf!=0;
}
#endif
/* 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.
*/
static SQLITE_NOINLINE int btreeLast(BtCursor *pCur, int *pRes){
int rc = moveToRoot(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
*pRes = 0;
rc = moveToRightmost(pCur);
if( rc==SQLITE_OK ){
pCur->curFlags |= BTCF_AtLast;
pCur->curFlags &= ~BTCF_AtLast;
}
}else if( rc==SQLITE_EMPTY ){
assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
*pRes = 1;
rc = SQLITE_OK;
}
return rc;
}
SQLITE_PRIVATE int sqlite3BtreeLast(BtCursor *pCur, int *pRes){
assert( cursorOwnsBtShared(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
/* If the cursor already points to the last entry, this is a no-op. */
if( CURSOR_VALID==pCur->eState && (pCur->curFlags & BTCF_AtLast)!=0 ){
assert( cursorIsAtLastEntry(pCur) || CORRUPT_DB );
*pRes = 0;
return SQLITE_OK;
}
return btreeLast(pCur, pRes);
}
/* Move the cursor so that it points to an entry in a table (a.k.a INTKEY)
** table near the key intKey. Return a success code.
**
** 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.
**
** An integer is written into *pRes which is the result of
** comparing the key with the entry to which the cursor is
** pointing. The meaning of the integer written into
** *pRes is as follows:
**
** *pRes<0 The cursor is left pointing at an entry that
** is smaller than intKey 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 intKey.
**
** *pRes>0 The cursor is left pointing at an entry that
** is larger than intKey.
*/
SQLITE_PRIVATE int sqlite3BtreeTableMoveto(
BtCursor *pCur, /* The cursor to be moved */
i64 intKey, /* The table key */
int biasRight, /* If true, bias the search to the high end */
int *pRes /* Write search results here */
){
int rc;
assert( cursorOwnsBtShared(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert( pRes );
assert( pCur->pKeyInfo==0 );
assert( pCur->eState!=CURSOR_VALID || pCur->curIntKey!=0 );
/* 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->curFlags & BTCF_ValidNKey)!=0 ){
if( pCur->info.nKey==intKey ){
*pRes = 0;
return SQLITE_OK;
}
if( pCur->info.nKey<intKey ){
if( (pCur->curFlags & BTCF_AtLast)!=0 ){
assert( cursorIsAtLastEntry(pCur) || CORRUPT_DB );
*pRes = -1;
return SQLITE_OK;
}
/* If the requested key is one more than the previous key, then
** try to get there using sqlite3BtreeNext() rather than a full
** binary search. This is an optimization only. The correct answer
** is still obtained without this case, only a little more slowly. */
if( pCur->info.nKey+1==intKey ){
*pRes = 0;
rc = sqlite3BtreeNext(pCur, 0);
assert( pCur->iPage==0 || pCur->apPage[0]->intKey==pCur->curIntKey );
assert( pCur->curIntKey );
for(;;){
int lwr, upr, idx, c;
Pgno chldPg;
MemPage *pPage = pCur->pPage;
u8 *pCell; /* Pointer to current cell in pPage */
/* pPage->nCell must be greater than zero. If this is the root-page
** the cursor would have been INVALID above and this for(;;) loop
** not run. If this is not the root-page, then the moveToChild() routine
** would have already detected db corruption. Similarly, pPage must
** be the right kind (index or table) of b-tree page. Otherwise
** a moveToChild() or moveToRoot() call would have detected corruption. */
assert( pPage->nCell>0 );
assert( pPage->intKey );
lwr = 0;
upr = pPage->nCell-1;
assert( biasRight==0 || biasRight==1 );
idx = upr>>(1-biasRight); /* idx = biasRight ? upr : (lwr+upr)/2; */
rc = moveToChild(pCur, chldPg);
if( rc ) break;
}
moveto_table_finish:
pCur->info.nSize = 0;
assert( (pCur->curFlags & BTCF_ValidOvfl)==0 );
return rc;
}
/*
** Compare the "idx"-th cell on the page the cursor pCur is currently
** pointing to to pIdxKey using xRecordCompare. Return negative or
** zero if the cell is less than or equal pIdxKey. Return positive
** if unknown.
**
** Return value negative: Cell at pCur[idx] less than pIdxKey
**
** Return value is zero: Cell at pCur[idx] equals pIdxKey
**
** Return value positive: Nothing is known about the relationship
** of the cell at pCur[idx] and pIdxKey.
** the optimization. */
c = 99;
}
return c;
}
/*
** Return true (non-zero) if pCur is current pointing to the last
** page of a table.
*/
static int cursorOnLastPage(BtCursor *pCur){
int i;
assert( pCur->eState==CURSOR_VALID );
for(i=0; i<pCur->iPage; i++){
MemPage *pPage = pCur->apPage[i];
if( pCur->aiIdx[i]<pPage->nCell ) return 0;
}
return 1;
}
/* Move the cursor so that it points to an entry in an index table
** near the key pIdxKey. Return a success code.
**
** 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.
**
** An integer is written into *pRes which is the result of
** comparing the key with the entry to which the cursor is
** pointing. The meaning of the integer written into
** *pRes is as follows:
**
** *pRes<0 The cursor is left pointing at an entry that
** is smaller than pIdxKey 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 pIdxKey.
**
** *pRes>0 The cursor is left pointing at an entry that
** is larger than pIdxKey.
**
** The pIdxKey->eqSeen field is set to 1 if there
** exists an entry in the table that exactly matches pIdxKey.
*/
SQLITE_PRIVATE int sqlite3BtreeIndexMoveto(
BtCursor *pCur, /* The cursor to be moved */
UnpackedRecord *pIdxKey, /* Unpacked index key */
int *pRes /* Write search results here */
){
int rc;
RecordCompare xRecordCompare;
assert( cursorOwnsBtShared(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert( pRes );
assert( pCur->pKeyInfo!=0 );
#ifdef SQLITE_DEBUG
pCur->pBtree->nSeek++; /* Performance measurement during testing */
#endif
xRecordCompare = sqlite3VdbeFindCompare(pIdxKey);
pIdxKey->errCode = 0;
assert( pIdxKey->default_rc==1
|| pIdxKey->default_rc==0
|| pIdxKey->default_rc==-1
);
/* Check to see if we can skip a lot of work. Two cases:
**
** (1) If the cursor is already pointing to the very last cell
** in the table and the pIdxKey search key is greater than or
** equal to that last cell, then no movement is required.
**
** (2) If the cursor is on the last page of the table and the first
** cell on that last page is less than or equal to the pIdxKey
** search key, then we can start the search on the current page
** without needing to go back to root.
*/
if( pCur->eState==CURSOR_VALID
&& pCur->pPage->leaf
&& cursorOnLastPage(pCur)
){
int c;
if( pCur->ix==pCur->pPage->nCell-1
&& (c = indexCellCompare(pCur, pCur->ix, pIdxKey, xRecordCompare))<=0
&& pIdxKey->errCode==SQLITE_OK
){
*pRes = c;
return SQLITE_OK; /* Cursor already pointing at the correct spot */
}
if( pCur->iPage>0
assert( pCur->pPage->nCell > 0 );
assert( pCur->curIntKey==0 );
assert( pIdxKey!=0 );
for(;;){
int lwr, upr, idx, c;
Pgno chldPg;
MemPage *pPage = pCur->pPage;
u8 *pCell; /* Pointer to current cell in pPage */
/* pPage->nCell must be greater than zero. If this is the root-page
** the cursor would have been INVALID above and this for(;;) loop
** not run. If this is not the root-page, then the moveToChild() routine
** would have already detected db corruption. Similarly, pPage must
** be the right kind (index or table) of b-tree page. Otherwise
** a moveToChild() or moveToRoot() call would have detected corruption. */
assert( pPage->nCell>0 );
assert( pPage->intKey==0 );
lwr = 0;
upr = pPage->nCell-1;
idx = upr>>1; /* idx = (lwr+upr)/2; */
for(;;){
***** End of in-lined moveToChild() call */
}
moveto_index_finish:
pCur->info.nSize = 0;
assert( (pCur->curFlags & BTCF_ValidOvfl)==0 );
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 an estimate for the number of rows in the table that pCur is
** pointing to. Return a negative number if no estimate is currently
** available.
*/
SQLITE_PRIVATE i64 sqlite3BtreeRowCountEst(BtCursor *pCur){
i64 n;
u8 i;
assert( cursorOwnsBtShared(pCur) );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
/* Currently this interface is only called by the OP_IfSizeBetween
** opcode and the OP_Count opcode with P3=1. In either case,
** the cursor will always be valid unless the btree is empty. */
if( pCur->eState!=CURSOR_VALID ) return 0;
if( NEVER(pCur->pPage->leaf==0) ) return -1;
n = pCur->pPage->nCell;
for(i=0; i<pCur->iPage; i++){
n *= pCur->apPage[i]->nCell;
}
return n;
}
/*
** Advance the cursor to the next entry in the database.
** Return value:
**
** SQLITE_OK success
** SQLITE_DONE cursor is already pointing at the last element
** otherwise some kind of error occurred
**
** The main entry point is sqlite3BtreeNext(). That routine is optimized
** for the common case of merely incrementing the cell counter BtCursor.aiIdx
** to the next cell on the current page. The (slower) btreeNext() helper
** routine is called when it is necessary to move to a different page or
** to restore the cursor.
**
** If bit 0x01 of the F argument in sqlite3BtreeNext(C,F) is 1, then the
** cursor corresponds to an SQL index and this routine could have been
** skipped if the SQL index had been a unique index. The F argument
** is a hint to the implement. SQLite btree implementation does not use
** this hint, but COMDB2 does.
*/
static SQLITE_NOINLINE int btreeNext(BtCursor *pCur){
int rc;
int idx;
MemPage *pPage;
assert( cursorOwnsBtShared(pCur) );
if( pCur->eState!=CURSOR_VALID ){
assert( (pCur->curFlags & BTCF_ValidOvfl)==0 );
rc = restoreCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
if( CURSOR_INVALID==pCur->eState ){
return SQLITE_DONE;
}
if( pCur->eState==CURSOR_SKIPNEXT ){
}
if( pPage->leaf ){
return SQLITE_OK;
}else{
return moveToLeftmost(pCur);
}
}
SQLITE_PRIVATE int sqlite3BtreeNext(BtCursor *pCur, int flags){
MemPage *pPage;
UNUSED_PARAMETER( flags ); /* Used in COMDB2 but not native SQLite */
assert( cursorOwnsBtShared(pCur) );
assert( flags==0 || flags==1 );
pCur->info.nSize = 0;
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
if( pCur->eState!=CURSOR_VALID ) return btreeNext(pCur);
pPage = pCur->pPage;
if( (++pCur->ix)>=pPage->nCell ){
pCur->ix--;
return btreeNext(pCur);
}
if( pPage->leaf ){
return SQLITE_OK;
}else{
return moveToLeftmost(pCur);
}
}
/*
** Step the cursor to the back to the previous entry in the database.
** Return values:
**
** SQLITE_OK success
** SQLITE_DONE the cursor is already on the first element of the table
** otherwise some kind of error occurred
**
** The main entry point is sqlite3BtreePrevious(). That routine is optimized
** for the common case of merely decrementing the cell counter BtCursor.aiIdx
** to the previous cell on the current page. The (slower) btreePrevious()
** helper routine is called when it is necessary to move to a different page
** or to restore the cursor.
**
** If bit 0x01 of the F argument to sqlite3BtreePrevious(C,F) is 1, then
** the cursor corresponds to an SQL index and this routine could have been
** skipped if the SQL index had been a unique index. The F argument is a
** hint to the implement. The native SQLite btree implementation does not
** use this hint, but COMDB2 does.
*/
static SQLITE_NOINLINE int btreePrevious(BtCursor *pCur){
int rc;
MemPage *pPage;
assert( cursorOwnsBtShared(pCur) );
assert( (pCur->curFlags & (BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey))==0 );
assert( pCur->info.nSize==0 );
if( pCur->eState!=CURSOR_VALID ){
rc = restoreCursorPosition(pCur);
if( rc!=SQLITE_OK ){
return rc;
}
if( CURSOR_INVALID==pCur->eState ){
return SQLITE_DONE;
}
pPage = pCur->pPage;
if( pPage->intKey && !pPage->leaf ){
rc = sqlite3BtreePrevious(pCur, 0);
}else{
rc = SQLITE_OK;
}
}
return rc;
}
SQLITE_PRIVATE int sqlite3BtreePrevious(BtCursor *pCur, int flags){
assert( cursorOwnsBtShared(pCur) );
assert( flags==0 || flags==1 );
UNUSED_PARAMETER( flags ); /* Used in COMDB2 but not native SQLite */
pCur->curFlags &= ~(BTCF_AtLast|BTCF_ValidOvfl|BTCF_ValidNKey);
pCur->info.nSize = 0;
if( pCur->eState!=CURSOR_VALID
|| pCur->ix==0
|| pCur->pPage->leaf==0
){
return btreePrevious(pCur);
}
return SQLITE_CORRUPT_BKPT;
}
if( nOvfl ){
rc = getOverflowPage(pBt, ovflPgno, &pOvfl, &iNext);
if( rc ) return rc;
}
if( ( pOvfl || ((pOvfl = btreePageLookup(pBt, ovflPgno))!=0) )
&& sqlite3PagerPageRefcount(pOvfl->pDbPage)!=1
){
/* There is no reason any cursor should have an outstanding reference
** to an overflow page belonging to a cell that is being deleted/updated.
** So if there exists more than one reference to this page, then it
** must not really be an overflow page and the database must be corrupt.
** It is helpful to detect this before calling freePage2(), as
** freePage2() may zero the page contents if secure-delete mode is
** enabled. If this 'overflow' page happens to be a page that the
** caller is iterating through or using in some other way, this
** can be problematic.
*/
rc = SQLITE_CORRUPT_BKPT;
/* Zero the contents of pRoot. Then install pChild as the right-child. */
zeroPage(pRoot, pChild->aData[0] & ~PTF_LEAF);
put4byte(&pRoot->aData[pRoot->hdrOffset+8], pgnoChild);
*ppChild = pChild;
return SQLITE_OK;
}
/*
** Return SQLITE_CORRUPT if any cursor other than pCur is currently valid
** on the same B-tree as pCur.
**
** This can occur if a database is corrupt with two or more SQL tables
** pointing to the same b-tree. If an insert occurs on one SQL table
** and causes a BEFORE TRIGGER to do a secondary insert on the other SQL
** table linked to the same b-tree. If the secondary insert causes a
** rebalance, that can change content out from under the cursor on the
** first SQL table, violating invariants on the first insert.
*/
static int anotherValidCursor(BtCursor *pCur){
BtCursor *pOther;
for(pOther=pCur->pBt->pCursor; pOther; pOther=pOther->pNext){
if( pOther!=pCur
&& pOther->eState==CURSOR_VALID
&& pOther->pPage==pCur->pPage
){
return SQLITE_CORRUPT_PAGE(pCur->pPage);
** buffers to overlap. This is harmless since the database is already
** corrupt but it does cause valgrind and ASAN warnings. So use
** memmove(). */
memmove(pDest, ((u8*)pX->pData) + iOffset, iAmt);
}
}
return SQLITE_OK;
}
/*
** Overwrite the cell that cursor pCur is pointing to with fresh content
** contained in pX. In this variant, pCur is pointing to an overflow
** cell.
*/
static SQLITE_NOINLINE int btreeOverwriteOverflowCell(
BtCursor *pCur, /* Cursor pointing to cell to overwrite */
const BtreePayload *pX /* Content to write into the cell */
){
int iOffset; /* Next byte of pX->pData to write */
int nTotal = pX->nData + pX->nZero; /* Total bytes of to write */
int rc; /* Return code */
iOffset, ovflPageSize);
}
sqlite3PagerUnref(pPage->pDbPage);
if( rc ) return rc;
iOffset += ovflPageSize;
}while( iOffset<nTotal );
return SQLITE_OK;
}
/*
** Overwrite the cell that cursor pCur is pointing to with fresh content
** contained in pX.
*/
static int btreeOverwriteCell(BtCursor *pCur, const BtreePayload *pX){
int nTotal = pX->nData + pX->nZero; /* Total bytes of to write */
MemPage *pPage = pCur->pPage; /* Page being written */
if( pCur->info.pPayload + pCur->info.nLocal > pPage->aDataEnd
|| pCur->info.pPayload < pPage->aData + pPage->cellOffset
){
return SQLITE_CORRUPT_PAGE(pPage);
0, pCur->info.nLocal);
}else{
/* The cell contains overflow content */
return btreeOverwriteOverflowCell(pCur, pX);
}
}
/*
** Insert a new record into the BTree. The content of the new record
** is described by the pX object. The pCur cursor is used only to
** define what table the record should be inserted into, and is left
** pointing at a random location.
**
** For a table btree (used for rowid tables), only the pX.nKey value of
** the key is used. The pX.pKey value must be NULL. The pX.nKey is the
** rowid or INTEGER PRIMARY KEY of the row. The pX.nData,pData,nZero fields
** hold the content of the row.
**
** For an index btree (used for indexes and WITHOUT ROWID tables), the
** key is an arbitrary byte sequence stored in pX.pKey,nKey. The
** pX.pData,nData,nZero fields must be zero.
**
** If the seekResult parameter is non-zero, then a successful call to
** sqlite3BtreeIndexMoveto() to seek cursor pCur to (pKey,nKey) has already
** been performed. In other words, if seekResult!=0 then the cursor
** is currently pointing to a cell that will be adjacent to the cell
** to be inserted. If seekResult<0 then pCur points to a cell that is
** smaller then (pKey,nKey). If seekResult>0 then pCur points to a cell
** that is larger than (pKey,nKey).
**
** If seekResult==0, that means pCur is pointing at some unknown location.
** In that case, this routine must seek the cursor to the correct insertion
** point for (pKey,nKey) before doing the insertion. For index btrees,
** if pX->nMem is non-zero, then pX->aMem contains pointers to the unpacked
** key values and pX->aMem can be used instead of pX->pKey to avoid having
** to decode the key.
*/
SQLITE_PRIVATE int sqlite3BtreeInsert(
BtCursor *pCur, /* Insert data into the table of this cursor */
const BtreePayload *pX, /* Content of the row to be inserted */
int flags, /* True if this is likely an append */
int seekResult /* Result of prior IndexMoveto() call */
){
int rc;
int loc = seekResult; /* -1: before desired location +1: after */
int szNew = 0;
int idx;
MemPage *pPage;
Btree *p = pCur->pBtree;
unsigned char *oldCell;
unsigned char *newCell = 0;
assert( (flags & (BTREE_SAVEPOSITION|BTREE_APPEND|BTREE_PREFORMAT))==flags );
assert( (flags & BTREE_PREFORMAT)==0 || seekResult || pCur->pKeyInfo==0 );
/* Save the positions of any other cursors open on this table.
**
** In some cases, the call to btreeMoveto() below is a no-op. For
** example, when inserting data into a table with auto-generated integer
** keys, the VDBE layer invokes sqlite3BtreeLast() to figure out the
** integer key to use. It then calls this function to actually insert the
** data into the intkey B-Tree. In this case btreeMoveto() recognizes
** that the cursor is already where it needs to be and returns without
** doing any work. To avoid thwarting these optimizations, it is important
** not to clear the cursor here.
*/
if( pCur->curFlags & BTCF_Multiple ){
rc = saveAllCursors(p->pBt, pCur->pgnoRoot, pCur);
if( rc ) return rc;
if( loc && pCur->iPage<0 ){
/* This can only happen if the schema is corrupt such that there is more
** than one table or index with the same root page as used by the cursor.
** Which can only happen if the SQLITE_NoSchemaError flag was set when
** the schema was loaded. This cannot be asserted though, as a user might
** set the flag, load the schema, and then unset the flag. */
return SQLITE_CORRUPT_PGNO(pCur->pgnoRoot);
}
}
/* Ensure that the cursor is not in the CURSOR_FAULT state and that it
** points to a valid cell.
*/
if( pCur->eState>=CURSOR_REQUIRESEEK ){
testcase( pCur->eState==CURSOR_REQUIRESEEK );
testcase( pCur->eState==CURSOR_FAULT );
rc = moveToRoot(pCur);
if( rc && rc!=SQLITE_EMPTY ) return rc;
}
assert( cursorOwnsBtShared(pCur) );
assert( (pCur->curFlags & BTCF_WriteFlag)!=0
&& p->pBt->inTransaction==TRANS_WRITE
&& (p->pBt->btsFlags & BTS_READ_ONLY)==0 );
assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
/* Assert that the caller has been consistent. If this cursor was opened
** expecting an index b-tree, then the caller should be inserting blob
** keys with no associated data. If the cursor was opened expecting an
** intkey table, the caller should be inserting integer keys with a
** blob of associated data. */
assert( (flags & BTREE_PREFORMAT) || (pX->pKey==0)==(pCur->pKeyInfo==0) );
if( pCur->pKeyInfo==0 ){
assert( pX->pKey==0 );
/* If this is an insert into a table b-tree, invalidate any incrblob
** cursors open on the row being replaced */
if( p->hasIncrblobCur ){
invalidateIncrblobCursors(p, pCur->pgnoRoot, pX->nKey, 0);
}
/* If BTREE_SAVEPOSITION is set, the cursor must already be pointing
** to a row with the same key as the new entry being inserted.
*/
#ifdef SQLITE_DEBUG
if( flags & BTREE_SAVEPOSITION ){
assert( pCur->curFlags & BTCF_ValidNKey );
assert( pX->nKey==pCur->info.nKey );
assert( loc==0 );
}
#endif
/* On the other hand, BTREE_SAVEPOSITION==0 does not imply
** that the cursor is not pointing to a row to be overwritten.
** So do a complete check.
*/
if( (pCur->curFlags&BTCF_ValidNKey)!=0 && pX->nKey==pCur->info.nKey ){
/* The cursor is pointing to the entry that is to be
** overwritten */
assert( pX->nData>=0 && pX->nZero>=0 );
if( pCur->info.nSize!=0
&& pCur->info.nPayload==(u32)pX->nData+pX->nZero
){
/* New entry is the same size as the old. Do an overwrite */
return btreeOverwriteCell(pCur, pX);
}
assert( loc==0 );
}else if( loc==0 ){
/* The cursor is *not* pointing to the cell to be overwritten, nor
** to an adjacent cell. Move the cursor so that it is pointing either
** to the cell to be overwritten or an adjacent cell.
*/
rc = sqlite3BtreeTableMoveto(pCur, pX->nKey,
(flags & BTREE_APPEND)!=0, &loc);
if( rc ) return rc;
}
}else{
/* This is an index or a WITHOUT ROWID table */
/* If BTREE_SAVEPOSITION is set, the cursor must already be pointing
** to a row with the same key as the new entry being inserted.
*/
assert( (flags & BTREE_SAVEPOSITION)==0 || loc==0 );
/* If the cursor is not already pointing either to the cell to be
** overwritten, or if a new cell is being inserted, if the cursor is
** not pointing to an immediately adjacent cell, then move the cursor
** so that it does.
*/
if( loc==0 && (flags & BTREE_SAVEPOSITION)==0 ){
if( pX->nMem ){
UnpackedRecord r;
r.pKeyInfo = pCur->pKeyInfo;
r.aMem = pX->aMem;
r.nField = pX->nMem;
r.default_rc = 0;
r.eqSeen = 0;
rc = sqlite3BtreeIndexMoveto(pCur, &r, &loc);
}else{
rc = btreeMoveto(pCur, pX->pKey, pX->nKey,
(flags & BTREE_APPEND)!=0, &loc);
}
if( rc ) return rc;
}
/* If the cursor is currently pointing to an entry to be overwritten
** and the new content is the same as as the old, then use the
** overwrite optimization.
*/
if( loc==0 ){
getCellInfo(pCur);
if( pCur->info.nKey==pX->nKey ){
BtreePayload x2;
x2.pData = pX->pKey;
x2.nData = pX->nKey;
x2.nZero = 0;
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
}else{
assert( pPage->leaf );
}
rc = insertCellFast(pPage, idx, newCell, szNew);
assert( pPage->nOverflow==0 || rc==SQLITE_OK );
assert( rc!=SQLITE_OK || pPage->nCell>0 || pPage->nOverflow>0 );
/* If no error has occurred and pPage has an overflow cell, call balance()
** to redistribute the cells within the tree. Since balance() may move
** the cursor, zero the BtCursor.info.nSize and BTCF_ValidNKey
** variables.
**
** Previous versions of SQLite called moveToRoot() to move the cursor
** back to the root page as balance() used to invalidate the contents
** of BtCursor.apPage[] and BtCursor.aiIdx[]. Instead of doing that,
** set the cursor state to "invalid". This makes common insert operations
** slightly faster.
**
** There is a subtle but important optimization here too. When inserting
** multiple records into an intkey b-tree using a single cursor (as can
** happen while processing an "INSERT INTO ... SELECT" statement), it
** is advantageous to leave the cursor pointing to the last entry in
** the b-tree if possible. If the cursor is left pointing to the last
** entry in the table, and the next row inserted has an integer key
** larger than the largest existing key, it is possible to insert the
** row without seeking the cursor. This can be a big performance boost.
*/
if( pPage->nOverflow ){
assert( rc==SQLITE_OK );
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
rc = balance(pCur);
/* Must make sure nOverflow is reset to zero even if the balance()
** fails. Internal data structure corruption will result otherwise.
** Also, set the cursor state to invalid. This stops saveCursorPosition()
** from trying to save the current position of the cursor. */
pCur->pPage->nOverflow = 0;
pCur->eState = CURSOR_INVALID;
if( (flags & BTREE_SAVEPOSITION) && rc==SQLITE_OK ){
btreeReleaseAllCursorPages(pCur);
if( pCur->pKeyInfo ){
assert( pCur->pKey==0 );
pCur->pKey = sqlite3Malloc( pX->nKey );
if( pCur->pKey==0 ){
rc = SQLITE_NOMEM;
}else{
pCur->nKey = pX->nKey;
}
}
assert( pCur->iPage<0 || pCur->pPage->nOverflow==0 );
end_insert:
return rc;
}
/*
** This function is used as part of copying the current row from cursor
** pSrc into cursor pDest. If the cursors are open on intkey tables, then
** parameter iKey is used as the rowid value when the record is copied
** into pDest. Otherwise, the record is copied verbatim.
**
** This function does not actually write the new value to cursor pDest.
** Instead, it creates and populates any required overflow pages and
** writes the data for the new cell into the BtShared.pTmpSpace buffer
** for the destination database. The size of the cell, in bytes, is left
** in BtShared.nPreformatSize. The caller completes the insertion by
** calling sqlite3BtreeInsert() with the BTREE_PREFORMAT flag specified.
**
** SQLITE_OK is returned if successful, or an SQLite error code otherwise.
*/
SQLITE_PRIVATE int sqlite3BtreeTransferRow(BtCursor *pDest, BtCursor *pSrc, i64 iKey){
BtShared *pBt = pDest->pBt;
}
}while( nRem>0 && rc==SQLITE_OK );
releasePage(pPageOut);
sqlite3PagerUnref(pPageIn);
return rc;
}
}
/*
** Delete the entry that the cursor is pointing to.
**
** If the BTREE_SAVEPOSITION bit of the flags parameter is zero, then
** the cursor is left pointing at an arbitrary location after the delete.
** But if that bit is set, then the cursor is left in a state such that
** the next call to BtreeNext() or BtreePrev() moves it to the same row
** as it would have been on if the call to BtreeDelete() had been omitted.
**
** The BTREE_AUXDELETE bit of flags indicates that is one of several deletes
** associated with a single table entry and its indexes. Only one of those
** deletes is considered the "primary" delete. The primary delete occurs
** on a cursor that is not a BTREE_FORDELETE cursor. All but one delete
** operation on non-FORDELETE cursors is tagged with the AUXDELETE flag.
** The BTREE_AUXDELETE bit is a hint that is not used by this implementation,
** but which might be used by alternative storage engines.
*/
SQLITE_PRIVATE int sqlite3BtreeDelete(BtCursor *pCur, u8 flags){
Btree *p = pCur->pBtree;
BtShared *pBt = p->pBt;
int rc; /* Return code */
MemPage *pPage; /* Page to delete cell from */
unsigned char *pCell; /* Pointer to cell to delete */
int iCellIdx; /* Index of cell to delete */
int iCellDepth; /* Depth of node containing pCell */
CellInfo info; /* Size of the cell being deleted */
u8 bPreserve; /* Keep cursor valid. 2 for CURSOR_SKIPNEXT */
assert( cursorOwnsBtShared(pCur) );
assert( pBt->inTransaction==TRANS_WRITE );
assert( (pBt->btsFlags & BTS_READ_ONLY)==0 );
assert( pCur->curFlags & BTCF_WriteFlag );
assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
assert( !hasReadConflicts(p, pCur->pgnoRoot) );
assert( (flags & ~(BTREE_SAVEPOSITION | BTREE_AUXDELETE))==0 );
if( pCur->eState!=CURSOR_VALID ){
if( pCur->eState>=CURSOR_REQUIRESEEK ){
rc = btreeRestoreCursorPosition(pCur);
assert( rc!=SQLITE_OK || CORRUPT_DB || pCur->eState==CURSOR_VALID );
return SQLITE_CORRUPT_PAGE(pPage);
}
pCell = findCell(pPage, iCellIdx);
if( pPage->nFree<0 && btreeComputeFreeSpace(pPage) ){
return SQLITE_CORRUPT_PAGE(pPage);
}
if( pCell<&pPage->aCellIdx[pPage->nCell] ){
return SQLITE_CORRUPT_PAGE(pPage);
}
/* If the BTREE_SAVEPOSITION bit is on, then the cursor position must
** be preserved following this delete operation. If the current delete
** will cause a b-tree rebalance, then this is done by saving the cursor
** key and leaving the cursor in CURSOR_REQUIRESEEK state before
** returning.
**
** If the current delete will not cause a rebalance, then the cursor
** will be left in CURSOR_SKIPNEXT state pointing to the entry immediately
** before or after the deleted entry.
**
** The bPreserve value records which path is required:
**
** bPreserve==0 Not necessary to save the cursor position
** bPreserve==1 Use CURSOR_REQUIRESEEK to save the cursor position
** bPreserve==2 Cursor won't move. Set CURSOR_SKIPNEXT.
*/
bPreserve = (flags & BTREE_SAVEPOSITION)!=0;
if( bPreserve ){
if( !pPage->leaf
|| (pPage->nFree+pPage->xCellSize(pPage,pCell)+2) >
(int)(pBt->usableSize*2/3)
|| pPage->nCell==1 /* See dbfuzz001.test for a test case */
){
/* A b-tree rebalance will be required after deleting this entry.
** Save the cursor key. */
rc = saveCursorKey(pCur);
if( rc ) return rc;
}else{
bPreserve = 2;
}
}
/* If the page containing the entry to delete is not a leaf page, move
** the cursor to the largest entry in the tree that is smaller than
** the entry being deleted. This cell will replace the cell being deleted
** from the internal node. The 'previous' entry is used for this instead
** of the 'next' entry, as the previous entry is always a part of the
** sub-tree headed by the child page of the cell being deleted. This makes
** balancing the tree following the delete operation easier. */
if( !pPage->leaf ){
rc = sqlite3BtreePrevious(pCur, 0);
assert( rc!=SQLITE_DONE );
if( rc ) return rc;
}
/* Save the positions of any other cursors open on this table before
** making any modifications. */
if( pCur->curFlags & BTCF_Multiple ){
rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur);
if( rc ) return rc;
}
/* If this is a delete operation to remove a row from a table b-tree,
** invalidate any incrblob cursors open on the row being deleted. */
if( pCur->pKeyInfo==0 && p->hasIncrblobCur ){
invalidateIncrblobCursors(p, pCur->pgnoRoot, pCur->info.nKey, 0);
}
/* Make the page containing the entry to be deleted writable. Then free any
** overflow pages associated with the entry and finally remove the cell
** itself from within the page. */
rc = sqlite3PagerWrite(pPage->pDbPage);
if( rc ) return rc;
BTREE_CLEAR_CELL(rc, pPage, pCell, info);
dropCell(pPage, iCellIdx, info.nSize, &rc);
if( rc ) return rc;
/* If the cell deleted was not located on a leaf page, then the cursor
** is currently pointing to the largest entry in the sub-tree headed
** by the child-page of the cell that was just deleted from an internal
** node. The cell from the leaf node needs to be moved to the internal
** node to replace the deleted cell. */
if( !pPage->leaf ){
MemPage *pLeaf = pCur->pPage;
int nCell;
Pgno n;
unsigned char *pTmp;
assert( pTmp!=0 );
rc = sqlite3PagerWrite(pLeaf->pDbPage);
if( rc==SQLITE_OK ){
rc = insertCell(pPage, iCellIdx, pCell-4, nCell+4, pTmp, n);
}
dropCell(pLeaf, pLeaf->nCell-1, nCell, &rc);
if( rc ) return rc;
}
/* Balance the tree. If the entry deleted was located on a leaf page,
** then the cursor still points to that page. In this case the first
** call to balance() repairs the tree, and the if(...) condition is
** never true.
**
** Otherwise, if the entry deleted was on an internal node page, then
** pCur is pointing to the leaf page from which a cell was removed to
** replace the cell deleted from the internal node. This is slightly
** tricky as the leaf node may be underfull, and the internal node may
** be either under or overfull. In this case run the balancing algorithm
** on the leaf node first. If the balance proceeds far enough up the
** tree that we can be sure that any problem in the internal node has
** been corrected, so be it. Otherwise, after balancing the leaf node,
** walk the cursor up the tree to the internal node and balance it as
** well. */
assert( pCur->pPage->nOverflow==0 );
assert( pCur->pPage->nFree>=0 );
if( pCur->pPage->nFree*3<=(int)pCur->pBt->usableSize*2 ){
/* Optimization: If the free space is less than 2/3rds of the page,
** then balance() will always be a no-op. No need to invoke it. */
rc = SQLITE_OK;
}else{
rc = balance(pCur);
}
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).
*/
sqlite3BtreeGetMeta(p, BTREE_LARGEST_ROOT_PAGE, &pgnoRoot);
if( pgnoRoot>btreePagecount(pBt) ){
return SQLITE_CORRUPT_PGNO(pgnoRoot);
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 = 0;
Pgno iPtrPage = 0;
/* Save the positions of any open cursors. This is required in
** case they are holding a reference to an xFetch reference
** corresponding to page pgnoRoot. */
rc = saveAllCursors(pBt, 0, 0);
releasePage(pPageMove);
if( rc!=SQLITE_OK ){
return rc;
}
/* Move the page currently at pgnoRoot to pgnoMove. */
rc = btreeGetPage(pBt, pgnoRoot, &pRoot, 0);
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.
**
** If pnChange is not NULL, then the integer value pointed to by pnChange
** is incremented by the number of entries in the table.
*/
SQLITE_PRIVATE int sqlite3BtreeClearTable(Btree *p, int iTable, i64 *pnChange){
int rc;
BtShared *pBt = p->pBt;
sqlite3BtreeEnter(p);
assert( p->inTrans==TRANS_WRITE );
rc = saveAllCursors(pBt, (Pgno)iTable, 0);
if( SQLITE_OK==rc ){
/* Invalidate all incrblob cursors open on table iTable (assuming iTable
** is the root of a table b-tree - if it is not, the following call is
** a no-op). */
if( p->hasIncrblobCur ){
invalidateIncrblobCursors(p, (Pgno)iTable, 0, 1);
}
rc = clearDatabasePage(pBt, (Pgno)iTable, 0, pnChange);
}
sqlite3BtreeLeave(p);
return rc;
}
SQLITE_PRIVATE int sqlite3BtreeClearTableOfCursor(BtCursor *pCur){
return sqlite3BtreeClearTable(pCur->pBtree, pCur->pgnoRoot, 0);
}
/*
** 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.
assert( iMeta==0 || iMeta==1 );
pBt->incrVacuum = (u8)iMeta;
}
#endif
}
sqlite3BtreeLeave(p);
return rc;
}
/*
** The first argument, pCur, is a cursor opened on some b-tree. Count the
** number of entries in the b-tree and write the result to *pnEntry.
**
** SQLITE_OK is returned if the operation is successfully executed.
** Otherwise, if an error is encountered (i.e. an IO error or database
** corruption) an SQLite error code is returned.
*/
SQLITE_PRIVATE int sqlite3BtreeCount(sqlite3 *db, BtCursor *pCur, i64 *pnEntry){
i64 nEntry = 0; /* Value to return in *pnEntry */
int rc; /* Return code */
/* If this is a leaf page or the tree is not an int-key tree, then
** this page contains countable entries. Increment the entry counter
** accordingly.
*/
pPage = pCur->pPage;
if( pPage->leaf || !pPage->intKey ){
nEntry += pPage->nCell;
}
/* pPage is a leaf node. This loop navigates the cursor so that it
** points to the first interior cell that it points to the parent of
** the next page in the tree that has not yet been visited. The
** pCur->aiIdx[pCur->iPage] value is set to the index of the parent cell
** of the page, or to the number of cells in the page if the next page
** to visit is the right-child of its parent.
**
** If all pages in the tree have been visited, return SQLITE_OK to the
** caller.
*/
if( pPage->leaf ){
*pnEntry = nEntry;
return moveToRoot(pCur);
}
moveToParent(pCur);
}while ( pCur->ix>=pCur->pPage->nCell );
pCur->ix++;
pPage = pCur->pPage;
}
/* Descend to the child node of the cell that the cursor currently
** points at. This is the right-child if (iIdx==pPage->nCell).
*/
iIdx = pCur->ix;
if( iIdx==pPage->nCell ){
rc = moveToChild(pCur, get4byte(&pPage->aData[pPage->hdrOffset+8]));
}else{
rc = moveToChild(pCur, get4byte(findCell(pPage, iIdx)));
}
}
rc = setSharedCacheTableLock(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. If this function is called with
** parameters that attempt to write past the end of the existing data,
** no modifications are made and SQLITE_CORRUPT is returned.
*/
SQLITE_PRIVATE int sqlite3BtreePutData(BtCursor *pCsr, u32 offset, u32 amt, void *z){
int rc;
assert( cursorOwnsBtShared(pCsr) );
assert( sqlite3_mutex_held(pCsr->pBtree->db->mutex) );
assert( pCsr->curFlags & BTCF_Incrblob );
rc = restoreCursorPosition(pCsr);
if( rc!=SQLITE_OK ){
return rc;
}
assert( pCsr->eState!=CURSOR_REQUIRESEEK );
if( pCsr->eState!=CURSOR_VALID ){
return SQLITE_ABORT;
}
/* Save the positions of all other cursors open on this table. This is
** required in case any of them are holding references to an xFetch
** version of the b-tree page modified by the accessPayload call below.
**
** Note that pCsr must be open on a INTKEY table and saveCursorPosition()
** and hence saveAllCursors() cannot fail on a BTREE_INTKEY table, hence
** saveAllCursors can only return SQLITE_OK.
*/
VVA_ONLY(rc =) saveAllCursors(pCsr->pBt, pCsr->pgnoRoot, pCsr);
assert( rc==SQLITE_OK );
/* Check some assumptions:
** (a) the cursor is open for writing,
** (b) there is a read/write transaction open,
** (c) the connection holds a write-lock on the table (if required),
** (d) there are no conflicting read-locks, and
** (e) the cursor points at a valid row of an intKey table.
*/
if( (pCsr->curFlags & BTCF_WriteFlag)==0 ){
return SQLITE_READONLY;
}
assert( (pCsr->pBt->btsFlags & BTS_READ_ONLY)==0
&& pCsr->pBt->inTransaction==TRANS_WRITE );
assert( hasSharedCacheTableLock(pCsr->pBtree, pCsr->pgnoRoot, 0, 2) );
assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
assert( pCsr->pPage->intKey );
return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
}
/*
** Mark this cursor as an incremental blob cursor.
*/
SQLITE_PRIVATE void sqlite3BtreeIncrblobCursor(BtCursor *pCur){
pCur->curFlags |= BTCF_Incrblob;
pCur->pBtree->hasIncrblobCur = 1;
}
#endif
/*
** Set both the "read version" (single byte at byte offset 18) and
** "write version" (single byte at byte offset 19) fields in the database
}
}
}
}
pBt->btsFlags &= ~BTS_NO_WAL;
return rc;
}
/*
** Return true if the cursor has a hint specified. This routine is
** only used from within assert() statements
*/
SQLITE_PRIVATE int sqlite3BtreeCursorHasHint(BtCursor *pCsr, unsigned int mask){
return (pCsr->hints & mask)!=0;
}
/*
** Return true if the given Btree is read-only.
*/
SQLITE_PRIVATE int sqlite3BtreeIsReadonly(Btree *p){
** true for this case to prevent the assert() in the callers frame
** from failing. */
return ( v->db->mallocFailed || hasAbort==mayAbort || hasFkCounter
|| (hasCreateTable && hasInitCoroutine) || hasCreateIndex
);
}
#endif /* SQLITE_DEBUG - the sqlite3AssertMayAbort() function */
#ifdef SQLITE_DEBUG
/*
** Increment the nWrite counter in the VDBE if the cursor is not an
** ephemeral cursor, or if the cursor argument is NULL.
*/
SQLITE_PRIVATE void sqlite3VdbeIncrWriteCounter(Vdbe *p, VdbeCursor *pC){
if( pC==0
|| (pC->eCurType!=CURTYPE_SORTER
&& pC->eCurType!=CURTYPE_PSEUDO
&& !pC->isEphemeral)
){
p->nWrite++;
}
}
** Use the sqlite3VdbeRewind() procedure to restore a virtual machine back
** to its initial state after it has been run.
*/
SQLITE_PRIVATE void sqlite3VdbeMakeReady(
Vdbe *p, /* The VDBE */
Parse *pParse /* Parsing context */
){
sqlite3 *db; /* The database connection */
int nVar; /* Number of parameters */
int nMem; /* Number of VM memory registers */
int nCursor; /* Number of cursors required */
int nArg; /* Number of arguments in subprograms */
int n; /* Loop counter */
struct ReusableSpace x; /* Reusable bulk memory */
assert( p!=0 );
assert( p->nOp>0 );
assert( pParse!=0 );
assert( p->eVdbeState==VDBE_INIT_STATE );
assert( pParse==p->pParse );
p->pVList = pParse->pVList;
pParse->pVList = 0;
db = p->db;
assert( db->mallocFailed==0 );
nVar = pParse->nVar;
nMem = pParse->nMem;
nCursor = pParse->nTab;
nArg = pParse->nMaxArg;
/* Each cursor uses a memory cell. The first cursor (cursor 0) can
** use aMem[0] which is not otherwise used by the VDBE program. Allocate
** space at the end of aMem[] for cursors 1 and greater.
** See also: allocateCursor().
*/
nMem += nCursor;
if( nCursor==0 && nMem>0 ) nMem++; /* Space for aMem[0] even if not used */
/* Figure out how much reusable memory is available at the end of the
** opcode array. This extra memory will be reallocated for other elements
** of the prepared statement.
*/
n = ROUND8P(sizeof(Op)*p->nOp); /* Bytes of opcode memory used */
resolveP2Values(p, &nArg);
p->usesStmtJournal = (u8)(pParse->isMultiWrite && pParse->mayAbort);
if( pParse->explain ){
if( nMem<10 ) nMem = 10;
p->explain = pParse->explain;
p->nResColumn = 12 - 4*p->explain;
}
p->expired = 0;
/* Memory for registers, parameters, cursor, etc, is allocated in one or two
** passes. On the first pass, we try to reuse unused memory at the
** end of the opcode array. If we are unable to satisfy all memory
** requirements by reusing the opcode array tail, then the second
** pass will fill in the remainder using a fresh memory allocation.
**
** This two-pass approach that reuses as much memory as possible from
** the leftover memory at the end of the opcode array. This can significantly
** reduce the amount of memory held by a prepared statement.
*/
x.nNeeded = 0;
p->nVar = (ynVar)nVar;
initMemArray(p->aVar, nVar, db, MEM_Null);
p->nMem = nMem;
initMemArray(p->aMem, nMem, db, MEM_Undefined);
memset(p->apCsr, 0, nCursor*sizeof(VdbeCursor*));
}
sqlite3VdbeRewind(p);
}
/*
** Close a VDBE cursor and release all the resources that cursor
** happens to hold.
*/
SQLITE_PRIVATE void sqlite3VdbeFreeCursor(Vdbe *p, VdbeCursor *pCx){
if( pCx ) sqlite3VdbeFreeCursorNN(p,pCx);
}
static SQLITE_NOINLINE void freeCursorWithCache(Vdbe *p, VdbeCursor *pCx){
VdbeTxtBlbCache *pCache = pCx->pCache;
assert( pCx->colCache );
pCx->colCache = 0;
pCx->pCache = 0;
sqlite3VdbeSorterClose(p->db, pCx);
break;
}
case CURTYPE_BTREE: {
assert( pCx->uc.pCursor!=0 );
sqlite3BtreeCloseCursor(pCx->uc.pCursor);
break;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
case CURTYPE_VTAB: {
sqlite3_vtab_cursor *pVCur = pCx->uc.pVCur;
const sqlite3_module *pModule = pVCur->pVtab->pModule;
assert( pVCur->pVtab->nRef>0 );
pVCur->pVtab->nRef--;
pModule->xClose(pVCur);
break;
}
#endif
}
}
/*
** Close all cursors in the current frame.
*/
static void closeCursorsInFrame(Vdbe *p){
int i;
for(i=0; i<p->nCursor; i++){
VdbeCursor *pC = p->apCsr[i];
if( pC ){
sqlite3VdbeFreeCursorNN(p, pC);
p->apCsr[i] = 0;
}
}
v->db->lastRowid = pFrame->lastRowid;
v->nChange = pFrame->nChange;
v->db->nChange = pFrame->nDbChange;
sqlite3VdbeDeleteAuxData(v->db, &v->pAuxData, -1, 0);
v->pAuxData = pFrame->pAuxData;
pFrame->pAuxData = 0;
return pFrame->pc;
}
/*
** Close all cursors.
**
** Also release any dynamic memory held by the VM in the Vdbe.aMem memory
** cell array. This is necessary as the memory cell array may contain
** pointers to VdbeFrame objects, which may in turn contain pointers to
** open cursors.
*/
static void closeAllCursors(Vdbe *p){
if( p->pFrame ){
VdbeFrame *pFrame;
for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent);
sqlite3VdbeFrameRestore(pFrame);
p->pFrame = 0;
p->nFrame = 0;
}
assert( p->nFrame==0 );
assert( p->ppVPrev!=0 );
*p->ppVPrev = p->pVNext;
if( p->pVNext ){
p->pVNext->ppVPrev = p->ppVPrev;
}
}
sqlite3DbNNFreeNN(db, p);
}
/*
** The cursor "p" has a pending seek operation that has not yet been
** carried out. Seek the cursor now. If an error occurs, return
** the appropriate error code.
*/
SQLITE_PRIVATE int SQLITE_NOINLINE sqlite3VdbeFinishMoveto(VdbeCursor *p){
int res, rc;
#ifdef SQLITE_TEST
extern int sqlite3_search_count;
#endif
assert( p->deferredMoveto );
assert( p->isTable );
assert( p->eCurType==CURTYPE_BTREE );
if( res!=0 ) return SQLITE_CORRUPT_BKPT;
#ifdef SQLITE_TEST
sqlite3_search_count++;
#endif
p->deferredMoveto = 0;
p->cacheStatus = CACHE_STALE;
return SQLITE_OK;
}
/*
** Something has moved cursor "p" out of place. Maybe the row it was
** pointed to was deleted out from under it. Or maybe the btree was
** rebalanced. Whatever the cause, try to restore "p" to the place it
** is supposed to be pointing. If the row was deleted out from under the
** cursor, set the cursor to point to a NULL row.
*/
SQLITE_PRIVATE int SQLITE_NOINLINE sqlite3VdbeHandleMovedCursor(VdbeCursor *p){
int isDifferentRow, rc;
assert( p->eCurType==CURTYPE_BTREE );
assert( p->uc.pCursor!=0 );
assert( sqlite3BtreeCursorHasMoved(p->uc.pCursor) );
rc = sqlite3BtreeCursorRestore(p->uc.pCursor, &isDifferentRow);
p->cacheStatus = CACHE_STALE;
if( isDifferentRow ) p->nullRow = 1;
return rc;
}
/*
** Check to ensure that the cursor is valid. Restore the cursor
** if need be. Return any I/O error from the restore operation.
*/
SQLITE_PRIVATE int sqlite3VdbeCursorRestore(VdbeCursor *p){
assert( p->eCurType==CURTYPE_BTREE || IsNullCursor(p) );
if( sqlite3BtreeCursorHasMoved(p->uc.pCursor) ){
return sqlite3VdbeHandleMovedCursor(p);
}
return SQLITE_OK;
}
/* Jump here if database corruption is detected after m has been
** allocated. Free the m object and return SQLITE_CORRUPT. */
idx_rowid_corruption:
testcase( m.szMalloc!=0 );
sqlite3VdbeMemReleaseMalloc(&m);
return SQLITE_CORRUPT_BKPT;
}
/*
** Compare the key of the index entry that cursor pC is pointing to against
** the key string in pUnpacked. Write into *pRes a number
** that is negative, zero, or positive if pC is less than, equal to,
** or greater than pUnpacked. Return SQLITE_OK on success.
**
** pUnpacked 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. Hence, this routine only compares the prefixes
** of the keys prior to the final rowid, not the entire key.
*/
SQLITE_PRIVATE int sqlite3VdbeIdxKeyCompare(
sqlite3 *db, /* Database connection */
VdbeCursor *pC, /* The cursor to compare against */
UnpackedRecord *pUnpacked, /* Unpacked version of key */
int *res /* Write the comparison result here */
){
i64 nCellKey = 0;
int rc;
BtCursor *pCur;
Mem m;
assert( pC->eCurType==CURTYPE_BTREE );
pCur = pC->uc.pCursor;
if( pMem->zMalloc ) sqlite3VdbeMemReleaseMalloc(pMem);
}
sqlite3DbNNFreeNN(db, p);
}
}
#endif /* SQLITE_ENABLE_PREUPDATE_HOOK */
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
/*
** Invoke the pre-update hook. If this is an UPDATE or DELETE pre-update call,
** then cursor passed as the second argument should point to the row about
** to be update or deleted. If the application calls sqlite3_preupdate_old(),
** the required value will be read from the row the cursor points to.
*/
SQLITE_PRIVATE void sqlite3VdbePreUpdateHook(
Vdbe *v, /* Vdbe pre-update hook is invoked by */
VdbeCursor *pCsr, /* Cursor to grab old.* values from */
int op, /* SQLITE_INSERT, UPDATE or DELETE */
const char *zDb, /* Database name */
Table *pTab, /* Modified table */
i64 iKey1, /* Initial key value */
int iReg, /* Register for new.* record */
int iBlobWrite
** be changed out from under the copy. This macro verifies that nothing
** like that ever happens.
*/
#ifdef SQLITE_DEBUG
# define memAboutToChange(P,M) sqlite3VdbeMemAboutToChange(P,M)
#else
# define memAboutToChange(P,M)
#endif
/*
** The following global variable is incremented every time a cursor
** moves, either by the OP_SeekXX, 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
/*
** 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 a string with P.z==P.zMalloc.
*/
#define Deephemeralize(P) \
if( ((P)->flags&MEM_Ephem)!=0 \
&& sqlite3VdbeMemMakeWriteable(P) ){ goto no_mem;}
/* Return true if the cursor was opened using the OP_OpenSorter opcode. */
#define isSorter(x) ((x)->eCurType==CURTYPE_SORTER)
/*
** Allocate VdbeCursor number iCur. Return a pointer to it. Return NULL
** if we run out of memory.
*/
static VdbeCursor *allocateCursor(
Vdbe *p, /* The virtual machine */
int iCur, /* Index of the new VdbeCursor */
int nField, /* Number of fields in the table or index */
u8 eCurType /* Type of the new cursor */
){
/* Find the memory cell that will be used to store the blob of memory
** required for this VdbeCursor structure. It is convenient to use a
** vdbe memory cell to manage the memory allocation required for a
** VdbeCursor 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.
**
** The memory cell for cursor 0 is aMem[0]. The rest are allocated from
** the top of the register space. Cursor 1 is at Mem[p->nMem-1].
** Cursor 2 is at Mem[p->nMem-2]. And so forth.
*/
Mem *pMem = iCur>0 ? &p->aMem[p->nMem-iCur] : p->aMem;
int nByte;
VdbeCursor *pCx = 0;
nByte =
ROUND8P(sizeof(VdbeCursor)) + 2*sizeof(u32)*nField +
(eCurType==CURTYPE_BTREE?sqlite3BtreeCursorSize():0);
assert( iCur>=0 && iCur<p->nCursor );
if( p->apCsr[iCur] ){ /*OPTIMIZATION-IF-FALSE*/
sqlite3VdbeFreeCursorNN(p, p->apCsr[iCur]);
p->apCsr[iCur] = 0;
}
/* There used to be a call to sqlite3VdbeMemClearAndResize() to make sure
** the pMem used to hold space for the cursor has enough storage available
** in pMem->zMalloc. But for the special case of the aMem[] entries used
** to hold cursors, it is faster to in-line the logic. */
assert( pMem->flags==MEM_Undefined );
assert( (pMem->flags & MEM_Dyn)==0 );
assert( pMem->szMalloc==0 || pMem->z==pMem->zMalloc );
if( pMem->szMalloc<nByte ){
if( pMem->szMalloc>0 ){
sqlite3DbFreeNN(pMem->db, pMem->zMalloc);
}
pMem->z = pMem->zMalloc = sqlite3DbMallocRaw(pMem->db, nByte);
if( pMem->zMalloc==0 ){
pMem->szMalloc = 0;
/*
** For OP_Column, factor out the case where content is loaded from
** overflow pages, so that the code to implement this case is separate
** the common case where all content fits on the page. Factoring out
** the code reduces register pressure and helps the common case
** to run faster.
*/
static SQLITE_NOINLINE int vdbeColumnFromOverflow(
VdbeCursor *pC, /* The BTree cursor from which we are reading */
int iCol, /* The column to read */
int t, /* The serial-type code for the column value */
i64 iOffset, /* Offset to the start of the content value */
u32 cacheStatus, /* Current Vdbe.cacheCtr value */
u32 colCacheCtr, /* Current value of the column cache counter */
Mem *pDest /* Store the value into this register. */
){
int rc;
sqlite3 *db = pDest->db;
int encoding = pDest->enc;
#ifdef SQLITE_DEBUG
if( pOp->p2==OE_Abort ){ sqlite3VdbeAssertAbortable(p); }
#endif
if( (pIn3->flags & MEM_Null)==0 ) break;
/* Fall through into OP_Halt */
/* no break */ deliberate_fall_through
}
/* 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.
**
}
break;
}
/* Opcode: IsType P1 P2 P3 P4 P5
** Synopsis: if typeof(P1.P3) in P5 goto P2
**
** Jump to P2 if the type of a column in a btree is one of the types specified
** by the P5 bitmask.
**
** P1 is normally a cursor on a btree for which the row decode cache is
** valid through at least column P3. In other words, there should have been
** a prior OP_Column for column P3 or greater. If the cursor is not valid,
** then this opcode might give spurious results.
** The the btree row has fewer than P3 columns, then use P4 as the
** datatype.
**
** If P1 is -1, then P3 is a register number and the datatype is taken
** from the value in that register.
**
** P5 is a bitmask of data types. SQLITE_INTEGER is the least significant
** (0x01) bit. SQLITE_FLOAT is the 0x02 bit. SQLITE_TEXT is 0x04.
** SQLITE_BLOB is 0x08. SQLITE_NULL is 0x10.
VdbeBranchTaken( (pIn1->flags & MEM_Null)==0, 2);
if( (pIn1->flags & MEM_Null)==0 ){
goto jump_to_p2;
}
break;
}
/* Opcode: IfNullRow P1 P2 P3 * *
** Synopsis: if P1.nullRow then r[P3]=NULL, goto P2
**
** Check the cursor P1 to see if it is currently pointing at a NULL row.
** If it is, then set register P3 to NULL and jump immediately to P2.
** If P1 is not on a NULL row, then fall through without making any
** changes.
**
** If P1 is not an open cursor, then this opcode is a no-op.
*/
case OP_IfNullRow: { /* jump */
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pC && pC->nullRow ){
sqlite3VdbeMemSetNull(aMem + pOp->p3);
goto jump_to_p2;
}
break;
}
#ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC
/* Opcode: Offset P1 P2 P3 * *
** Synopsis: r[P3] = sqlite_offset(P1)
**
** Store in register r[P3] the byte offset into the database file that is the
** start of the payload for the record at which that cursor P1 is currently
** pointing.
**
** P2 is the column number for the argument to the sqlite_offset() function.
** This opcode does not use P2 itself, but the P2 value is used by the
** code generator. The P1, P2, and P3 operands to this opcode are the
** same as for OP_Column.
**
** This opcode is only available if SQLite is compiled with the
** -DSQLITE_ENABLE_OFFSET_SQL_FUNC option.
*/
case OP_Offset: { /* out3 */
VdbeCursor *pC; /* The VDBE cursor */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
pOut = &p->aMem[pOp->p3];
if( pC==0 || pC->eCurType!=CURTYPE_BTREE ){
sqlite3VdbeMemSetNull(pOut);
}else{
if( pC->deferredMoveto ){
rc = sqlite3VdbeFinishMoveto(pC);
if( rc ) goto abort_due_to_error;
}
sqlite3VdbeMemSetNull(pOut);
}else{
sqlite3VdbeMemSetInt64(pOut, sqlite3BtreeOffset(pC->uc.pCursor));
}
}
break;
}
#endif /* SQLITE_ENABLE_OFFSET_SQL_FUNC */
/* Opcode: Column P1 P2 P3 P4 P5
** Synopsis: r[P3]=PX cursor P1 column P2
**
** 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 than (P2+1)
** values in the record, extract a NULL.
**
** The value extracted is stored in register P3.
**
** If the record 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.
**
** If the OPFLAG_LENGTHARG bit is set in P5 then the result is guaranteed
** to only be used by the length() function or the equivalent. The content
** of large blobs is not loaded, thus saving CPU cycles. If the
** OPFLAG_TYPEOFARG bit is set then the result will only be used by the
** typeof() function or the IS NULL or IS NOT NULL operators or the
** equivalent. In this case, all content loading can be omitted.
*/
case OP_Column: { /* ncycle */
u32 p2; /* column number to retrieve */
VdbeCursor *pC; /* The VDBE cursor */
BtCursor *pCrsr; /* The B-Tree cursor corresponding to pC */
u32 *aOffset; /* aOffset[i] is offset to start of data for i-th column */
int len; /* The length of the serialized data for the column */
int i; /* Loop counter */
Mem *pDest; /* Where to write the extracted value */
Mem sMem; /* For storing the record being decoded */
const u8 *zData; /* Part of the record being decoded */
const u8 *zHdr; /* Next unparsed byte of the header */
const u8 *zEndHdr; /* Pointer to first byte after the header */
u64 offset64; /* 64-bit offset */
u32 t; /* A type code from the record header */
|| (pC->eCurType==CURTYPE_PSEUDO && pC->seekResult==0) );
aOffset = pC->aOffset;
assert( aOffset==pC->aType+pC->nField );
assert( pC->eCurType!=CURTYPE_VTAB );
assert( pC->eCurType!=CURTYPE_PSEUDO || pC->nullRow );
assert( pC->eCurType!=CURTYPE_SORTER );
if( pC->cacheStatus!=p->cacheCtr ){ /*OPTIMIZATION-IF-FALSE*/
if( pC->nullRow ){
if( pC->eCurType==CURTYPE_PSEUDO && pC->seekResult>0 ){
/* For the special case of as pseudo-cursor, the seekResult field
** identifies the register that holds the record */
pReg = &aMem[pC->seekResult];
assert( pReg->flags & MEM_Blob );
assert( memIsValid(pReg) );
pC->payloadSize = pC->szRow = pReg->n;
pC->aRow = (u8*)pReg->z;
}else{
pDest = &aMem[pOp->p3];
memAboutToChange(p, pDest);
sqlite3VdbeMemSetNull(pDest);
assert( pOp->p3>0 && pOp->p3<=(p->nMem+1 - p->nCursor) );
REGISTER_TRACE(pOp->p3, pOut);
break;
}
/* Opcode: Count P1 P2 P3 * *
** Synopsis: r[P2]=count()
**
** Store the number of entries (an integer value) in the table or index
** opened by cursor P1 in register P2.
**
** If P3==0, then an exact count is obtained, which involves visiting
** every btree page of the table. But if P3 is non-zero, an estimate
** is returned based on the current cursor position.
*/
case OP_Count: { /* out2 */
i64 nEntry;
BtCursor *pCrsr;
assert( p->apCsr[pOp->p1]->eCurType==CURTYPE_BTREE );
pCrsr = p->apCsr[pOp->p1]->uc.pCursor;
assert( pCrsr );
if( pOp->p3 ){
nEntry = sqlite3BtreeRowCountEst(pCrsr);
/* Opcode: ReadCookie P1 P2 P3 * *
**
** Read cookie number P3 from database P1 and write it into register P2.
** P3==1 is the schema version. P3==2 is the database format.
** P3==3 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.
**
** 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 */
int iMeta;
int iDb;
int iCookie;
assert( p->bIsReader );
iDb = pOp->p1;
iCookie = pOp->p3;
sqlite3ExpirePreparedStatements(db, 0);
p->expired = 0;
}
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: OpenRead P1 P2 P3 P4 P5
** Synopsis: root=P2 iDb=P3
**
** 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.
**
** Allowed P5 bits:
** <ul>
** <li> <b>0x02 OPFLAG_SEEKEQ</b>: This cursor will only be used for
** equality lookups (implemented as a pair of opcodes OP_SeekGE/OP_IdxGT
** of OP_SeekLE/OP_IdxLT)
** </ul>
**
** The P4 value may be either an integer (P4_INT32) or a pointer to
** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo
** object, then table being opened must be an [index b-tree] where the
** KeyInfo object defines the content and collating
** sequence of that index b-tree. Otherwise, if P4 is an integer
** value, then the table being opened must be a [table b-tree] with a
** number of columns no less than the value of P4.
**
** See also: OpenWrite, ReopenIdx
*/
/* Opcode: ReopenIdx P1 P2 P3 P4 P5
** Synopsis: root=P2 iDb=P3
**
** The ReopenIdx opcode works like OP_OpenRead except that it first
** checks to see if the cursor on P1 is already open on the same
** b-tree and if it is this opcode becomes a no-op. In other words,
** if the cursor is already open, do not reopen it.
**
** The ReopenIdx opcode may only be used with P5==0 or P5==OPFLAG_SEEKEQ
** and with P4 being a P4_KEYINFO object. Furthermore, the P3 value must
** be the same as every other ReopenIdx or OpenRead for the same cursor
** number.
**
** Allowed P5 bits:
** <ul>
** <li> <b>0x02 OPFLAG_SEEKEQ</b>: This cursor will only be used for
** equality lookups (implemented as a pair of opcodes OP_SeekGE/OP_IdxGT
** of OP_SeekLE/OP_IdxLT)
** </ul>
**
** See also: OP_OpenRead, OP_OpenWrite
*/
/* Opcode: OpenWrite P1 P2 P3 P4 P5
** Synopsis: root=P2 iDb=P3
**
** Open a read/write cursor named P1 on the table or index whose root
** page is P2 (or whose root page is held in register P2 if the
** OPFLAG_P2ISREG bit is set in P5 - see below).
**
** The P4 value may be either an integer (P4_INT32) or a pointer to
** a KeyInfo structure (P4_KEYINFO). If it is a pointer to a KeyInfo
** object, then table being opened must be an [index b-tree] where the
** KeyInfo object defines the content and collating
** sequence of that index b-tree. Otherwise, if P4 is an integer
** value, then the table being opened must be a [table b-tree] with a
** number of columns no less than the value of P4.
**
** Allowed P5 bits:
** <ul>
** <li> <b>0x02 OPFLAG_SEEKEQ</b>: This cursor will only be used for
** equality lookups (implemented as a pair of opcodes OP_SeekGE/OP_IdxGT
** of OP_SeekLE/OP_IdxLT)
** <li> <b>0x08 OPFLAG_FORDELETE</b>: This cursor is used only to seek
** and subsequently delete entries in an index btree. This is a
** hint to the storage engine that the storage engine is allowed to
** ignore. The hint is not used by the official SQLite b*tree storage
** engine, but is used by COMDB2.
** <li> <b>0x10 OPFLAG_P2ISREG</b>: Use the content of register P2
** as the root page, not the value of P2 itself.
** </ul>
**
** This instruction works like OpenRead except that it opens the cursor
** in read/write mode.
**
** See also: OP_OpenRead, OP_ReopenIdx
*/
case OP_ReopenIdx: { /* ncycle */
int nField;
KeyInfo *pKeyInfo;
u32 p2;
int iDb;
int wrFlag;
VdbeCursor *pCur;
Db *pDb;
assert( pOp->p5==0 || pOp->p5==OPFLAG_SEEKEQ );
assert( pOp->p4type==P4_KEYINFO );
pCur = p->apCsr[pOp->p1];
if( pCur && pCur->pgnoRoot==(u32)pOp->p2 ){
assert( pCur->iDb==pOp->p3 ); /* Guaranteed by the code generator */
assert( pCur->eCurType==CURTYPE_BTREE );
sqlite3BtreeClearCursor(pCur->uc.pCursor);
goto open_cursor_set_hints;
}
/* If the cursor is not currently open or is open on a different
** index, then fall through into OP_OpenRead to force a reopen */
case OP_OpenRead: /* ncycle */
case OP_OpenWrite:
assert( pOp->opcode==OP_OpenWrite || pOp->p5==0 || pOp->p5==OPFLAG_SEEKEQ );
assert( p->bIsReader );
assert( pOp->opcode==OP_OpenRead || pOp->opcode==OP_ReopenIdx
|| p->readOnly==0 );
if( p->expired==1 ){
pCur->wrFlag = wrFlag;
#endif
rc = sqlite3BtreeCursor(pX, p2, wrFlag, pKeyInfo, pCur->uc.pCursor);
pCur->pKeyInfo = pKeyInfo;
/* Set the VdbeCursor.isTable variable. Previous versions of
** SQLite used to check if the root-page flags were sane at this point
** and report database corruption if they were not, but this check has
** since moved into the btree layer. */
pCur->isTable = pOp->p4type!=P4_KEYINFO;
open_cursor_set_hints:
assert( OPFLAG_BULKCSR==BTREE_BULKLOAD );
assert( OPFLAG_SEEKEQ==BTREE_SEEK_EQ );
testcase( pOp->p5 & OPFLAG_BULKCSR );
testcase( pOp->p2 & OPFLAG_SEEKEQ );
sqlite3BtreeCursorHintFlags(pCur->uc.pCursor,
(pOp->p5 & (OPFLAG_BULKCSR|OPFLAG_SEEKEQ)));
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: OpenDup P1 P2 * * *
**
** Open a new cursor P1 that points to the same ephemeral table as
** cursor P2. The P2 cursor must have been opened by a prior OP_OpenEphemeral
** opcode. Only ephemeral cursors may be duplicated.
**
** Duplicate ephemeral cursors are used for self-joins of materialized views.
*/
case OP_OpenDup: { /* ncycle */
VdbeCursor *pOrig; /* The original cursor to be duplicated */
VdbeCursor *pCx; /* The new cursor */
pOrig = p->apCsr[pOp->p2];
assert( pOrig );
assert( pOrig->isEphemeral ); /* Only ephemeral cursors can be duplicated */
pCx = allocateCursor(p, pOp->p1, pOrig->nField, CURTYPE_BTREE);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->isEphemeral = 1;
pCx->pKeyInfo = pOrig->pKeyInfo;
pCx->isTable = pOrig->isTable;
pCx->pgnoRoot = pOrig->pgnoRoot;
pCx->isOrdered = pOrig->isOrdered;
pCx->ub.pBtx = pOrig->ub.pBtx;
pCx->noReuse = 1;
pOrig->noReuse = 1;
rc = sqlite3BtreeCursor(pCx->ub.pBtx, pCx->pgnoRoot, BTREE_WRCSR,
pCx->pKeyInfo, pCx->uc.pCursor);
/* The sqlite3BtreeCursor() routine can only fail for the first cursor
** opened for a database. Since there is already an open cursor when this
** opcode is run, the sqlite3BtreeCursor() cannot fail */
assert( rc==SQLITE_OK );
break;
}
/* Opcode: OpenEphemeral P1 P2 P3 P4 P5
** Synopsis: nColumn=P2
**
** 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 ephemeral
** table is deleted automatically when the cursor is closed.
**
** If the cursor P1 is already opened on an ephemeral table, the table
** is cleared (all content is erased).
**
** P2 is the number of columns in the ephemeral 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.
**
** The P5 parameter can be a mask of the BTREE_* flags defined
** in btree.h. These flags control aspects of the operation of
** the btree. The BTREE_OMIT_JOURNAL and BTREE_SINGLE flags are
** added automatically.
**
** If P3 is positive, then reg[P3] is modified slightly so that it
** can be used as zero-length data for OP_Insert. This is an optimization
if( pCx==0 ) goto no_mem;
pCx->pKeyInfo = pOp->p4.pKeyInfo;
assert( pCx->pKeyInfo->db==db );
assert( pCx->pKeyInfo->enc==ENC(db) );
rc = sqlite3VdbeSorterInit(db, pOp->p3, pCx);
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: SequenceTest P1 P2 * * *
** Synopsis: if( cursor[P1].ctr++ ) pc = P2
**
** P1 is a sorter cursor. If the sequence counter is currently zero, jump
** to P2. Regardless of whether or not the jump is taken, increment the
** the sequence value.
*/
case OP_SequenceTest: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( isSorter(pC) );
if( (pC->seqCount++)==0 ){
goto jump_to_p2;
}
break;
}
/* Opcode: OpenPseudo P1 P2 P3 * *
** Synopsis: P3 columns in r[P2]
**
** Open a new cursor that points to a fake table that contains a single
** row of data. The content of that one row is the content of memory
** register P2. In other words, cursor P1 becomes an alias for the
** MEM_Blob content contained in register P2.
**
** A pseudo-table created by this opcode is used to hold a single
** row output from the sorter so that the row can be decomposed into
** individual columns using the OP_Column opcode. The OP_Column opcode
** is the only cursor opcode that works with a pseudo-table.
**
** P3 is the number of fields in the records that will be stored by
** the pseudo-table. If P2 is 0 or negative then the pseudo-cursor
** will return NULL for every column.
*/
case OP_OpenPseudo: {
VdbeCursor *pCx;
assert( pOp->p1>=0 );
assert( pOp->p3>=0 );
pCx = allocateCursor(p, pOp->p1, pOp->p3, CURTYPE_PSEUDO);
if( pCx==0 ) goto no_mem;
pCx->nullRow = 1;
pCx->seekResult = pOp->p2;
pCx->isTable = 1;
/* Give this pseudo-cursor a fake BtCursor pointer so that pCx
** can be safely passed to sqlite3VdbeCursorMoveto(). This avoids a test
** for pCx->eCurType==CURTYPE_BTREE inside of sqlite3VdbeCursorMoveto()
** which is a performance optimization */
pCx->uc.pCursor = sqlite3BtreeFakeValidCursor();
assert( pOp->p5==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: { /* ncycle */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
sqlite3VdbeFreeCursor(p, p->apCsr[pOp->p1]);
p->apCsr[pOp->p1] = 0;
break;
}
#ifdef SQLITE_ENABLE_COLUMN_USED_MASK
/* Opcode: ColumnsUsed P1 * * P4 *
**
** This opcode (which only exists if SQLite was compiled with
** SQLITE_ENABLE_COLUMN_USED_MASK) identifies which columns of the
** table or index for cursor P1 are used. P4 is a 64-bit integer
** (P4_INT64) in which the first 63 bits are one for each of the
** first 63 columns of the table or index that are actually used
** by the cursor. The high-order bit is set if any column after
** the 64th is used.
*/
case OP_ColumnsUsed: {
VdbeCursor *pC;
pC = p->apCsr[pOp->p1];
assert( pC->eCurType==CURTYPE_BTREE );
pC->maskUsed = *(u64*)pOp->p4.pI64;
break;
}
#endif
/* Opcode: SeekGE P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the value in register P3 as the 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.
**
** If the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
** opcode will either land on a record that exactly matches the key, or
** else it will cause a jump to P2. When the cursor is OPFLAG_SEEKEQ,
** this opcode must be followed by an IdxLE opcode with the same arguments.
** The IdxGT opcode will be skipped if this opcode succeeds, but the
** IdxGT opcode will be used on subsequent loop iterations. The
** OPFLAG_SEEKEQ flags is a hint to the btree layer to say that this
** is an equality search.
**
** This opcode leaves the cursor configured to move in forward order,
** from the beginning toward the end. In other words, the cursor is
** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGt, SeekLe
*/
/* Opcode: SeekGT P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the 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.
**
** This opcode leaves the cursor configured to move in forward order,
** from the beginning toward the end. In other words, the cursor is
** configured to use Next, not Prev.
**
** See also: Found, NotFound, SeekLt, SeekGe, SeekLe
*/
/* Opcode: SeekLT P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the 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.
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
** configured to use Prev, not Next.
**
** See also: Found, NotFound, SeekGt, SeekGe, SeekLe
*/
/* Opcode: SeekLE P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If cursor P1 refers to an SQL table (B-Tree that uses integer keys),
** use the 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.
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
** configured to use Prev, not Next.
**
** If the cursor P1 was opened using the OPFLAG_SEEKEQ flag, then this
** opcode will either land on a record that exactly matches the key, or
** else it will cause a jump to P2. When the cursor is OPFLAG_SEEKEQ,
** this opcode must be followed by an IdxLE opcode with the same arguments.
** The IdxGE opcode will be skipped if this opcode succeeds, but the
** IdxGE opcode will be used on subsequent loop iterations. The
** OPFLAG_SEEKEQ flags is a hint to the btree layer to say that this
** is an equality search.
**
** See also: Found, NotFound, SeekGt, SeekGe, SeekLt
*/
case OP_SeekLT: /* jump0, in3, group, ncycle */
case OP_SeekLE: /* jump0, in3, group, ncycle */
case OP_SeekGE: /* jump0, in3, group, ncycle */
case OP_SeekGT: { /* jump0, in3, group, ncycle */
int res; /* Comparison result */
int oc; /* Opcode */
VdbeCursor *pC; /* The cursor to seek */
UnpackedRecord r; /* The key to seek for */
int nField; /* Number of columns or fields in the key */
i64 iKey; /* The rowid we are to seek to */
int eqOnly; /* Only interested in == results */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
assert( pOp->p2!=0 );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE );
eqOnly = 0;
pC->nullRow = 0;
#ifdef SQLITE_DEBUG
pC->seekOp = pOp->opcode;
#endif
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
if( pC->isTable ){
u16 flags3, newType;
/* The OPFLAG_SEEKEQ/BTREE_SEEK_EQ flag is only set on index cursors */
assert( sqlite3BtreeCursorHasHint(pC->uc.pCursor, BTREE_SEEK_EQ)==0
|| CORRUPT_DB );
/* The input value in P3 might be of any type: integer, real, string,
** blob, or NULL. But it needs to be an integer before we can do
** the seek, so convert it. */
pIn3 = &aMem[pOp->p3];
flags3 = pIn3->flags;
if( (flags3 & (MEM_Int|MEM_Real|MEM_IntReal|MEM_Str))==MEM_Str ){
applyNumericAffinity(pIn3, 0);
assert( (OP_SeekLT & 0x0001)==(OP_SeekGE & 0x0001) );
if( (oc & 0x0001)==(OP_SeekLT & 0x0001) ) oc++;
}
}
rc = sqlite3BtreeTableMoveto(pC->uc.pCursor, (u64)iKey, 0, &res);
pC->movetoTarget = iKey; /* Used by OP_Delete */
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
}else{
/* For a cursor with the OPFLAG_SEEKEQ/BTREE_SEEK_EQ hint, only the
** OP_SeekGE and OP_SeekLE opcodes are allowed, and these must be
** immediately followed by an OP_IdxGT or OP_IdxLT opcode, respectively,
** with the same key.
*/
if( sqlite3BtreeCursorHasHint(pC->uc.pCursor, BTREE_SEEK_EQ) ){
eqOnly = 1;
assert( pOp->opcode==OP_SeekGE || pOp->opcode==OP_SeekLE );
assert( pOp[1].opcode==OP_IdxLT || pOp[1].opcode==OP_IdxGT );
assert( pOp->opcode==OP_SeekGE || pOp[1].opcode==OP_IdxLT );
assert( pOp->opcode==OP_SeekLE || pOp[1].opcode==OP_IdxGT );
** the P1, P2 and P5 operands of this opcode are also used, and are called
** This.P1, This.P2 and This.P5.
**
** This opcode helps to optimize IN operators on a multi-column index
** where the IN operator is on the later terms of the index by avoiding
** unnecessary seeks on the btree, substituting steps to the next row
** of the b-tree instead. A correct answer is obtained if this opcode
** is omitted or is a no-op.
**
** The SeekGE.P3 and SeekGE.P4 operands identify an unpacked key which
** is the desired entry that we want the cursor SeekGE.P1 to be pointing
** to. Call this SeekGE.P3/P4 row the "target".
**
** If the SeekGE.P1 cursor is not currently pointing to a valid row,
** then this opcode is a no-op and control passes through into the OP_SeekGE.
**
** If the SeekGE.P1 cursor is pointing to a valid row, then that row
** might be the target row, or it might be near and slightly before the
** target row, or it might be after the target row. If the cursor is
** currently before the target row, then this opcode attempts to position
** the cursor on or after the target row by invoking sqlite3BtreeStep()
** on the cursor between 1 and This.P1 times.
**
** The This.P5 parameter is a flag that indicates what to do if the
** cursor ends up pointing at a valid row that is past the target
** row. If This.P5 is false (0) then a jump is made to SeekGE.P2. If
** This.P5 is true (non-zero) then a jump is made to This.P2. The P5==0
** case occurs when there are no inequality constraints to the right of
** the IN constraint. The jump to SeekGE.P2 ends the loop. The P5!=0 case
** occurs when there are inequality constraints to the right of the IN
** operator. In that case, the This.P2 will point either directly to or
** to setup code prior to the OP_IdxGT or OP_IdxGE opcode that checks for
** loop terminate.
**
** Possible outcomes from this opcode:<ol>
**
** <li> If the cursor is initially not pointed to any valid row, then
** fall through into the subsequent OP_SeekGE opcode.
**
** <li> If the cursor is left pointing to a row that is before the target
** row, even after making as many as This.P1 calls to
** sqlite3BtreeNext(), then also fall through into OP_SeekGE.
**
** <li> If the cursor is left pointing at the target row, either because it
** was at the target row to begin with or because one or more
** sqlite3BtreeNext() calls moved the cursor to the target row,
** then jump to This.P2..,
**
** <li> If the cursor started out before the target row and a call to
** to sqlite3BtreeNext() moved the cursor off the end of the index
** (indicating that the target row definitely does not exist in the
** btree) then jump to SeekGE.P2, ending the loop.
**
** <li> If the cursor ends up on a valid row that is past the target row
** (indicating that the target row does not exist in the btree) then
** jump to SeekOP.P2 if This.P5==0 or to This.P2 if This.P5>0.
** </ol>
*/
case OP_SeekScan: { /* ncycle */
VdbeCursor *pC;
int res;
int nStep;
UnpackedRecord r;
#endif
assert( pOp->p1>0 );
pC = p->apCsr[pOp[1].p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE );
assert( !pC->isTable );
if( !sqlite3BtreeCursorIsValidNN(pC->uc.pCursor) ){
#ifdef SQLITE_DEBUG
if( db->flags&SQLITE_VdbeTrace ){
printf("... cursor not valid - fall through\n");
}
#endif
break;
}
nStep = pOp->p1;
assert( nStep>=1 );
r.pKeyInfo = pC->pKeyInfo;
r.nField = (u16)pOp[1].p4.i;
r.default_rc = 0;
r.aMem = &aMem[pOp[1].p3];
}
}
break;
}
/* Opcode: SeekHit P1 P2 P3 * *
** Synopsis: set P2<=seekHit<=P3
**
** Increase or decrease the seekHit value for cursor P1, if necessary,
** so that it is no less than P2 and no greater than P3.
**
** The seekHit integer represents the maximum of terms in an index for which
** there is known to be at least one match. If the seekHit value is smaller
** than the total number of equality terms in an index lookup, then the
** OP_IfNoHope opcode might run to see if the IN loop can be abandoned
** early, thus saving work. This is part of the IN-early-out optimization.
**
** P1 must be a valid b-tree cursor.
*/
case OP_SeekHit: { /* ncycle */
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pOp->p3>=pOp->p2 );
if( pC->seekHit<pOp->p2 ){
#ifdef SQLITE_DEBUG
if( db->flags&SQLITE_VdbeTrace ){
}
#endif
pC->seekHit = pOp->p3;
}
break;
}
/* Opcode: IfNotOpen P1 P2 * * *
** Synopsis: if( !csr[P1] ) goto P2
**
** If cursor P1 is not open or if P1 is set to a NULL row using the
** OP_NullRow opcode, then jump to instruction P2. Otherwise, fall through.
*/
case OP_IfNotOpen: { /* jump */
VdbeCursor *pCur;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pCur = p->apCsr[pOp->p1];
VdbeBranchTaken(pCur==0 || pCur->nullRow, 2);
if( pCur==0 || pCur->nullRow ){
goto jump_to_p2_and_check_for_interrupt;
** Synopsis: key=r[P3@P4]
**
** If P4==0 then register P3 holds a blob constructed by MakeRecord. If
** P4>0 then register P3 is the first of P4 registers that form an unpacked
** record.
**
** Cursor P1 is on an index btree. If the record identified by P3 and P4
** is a prefix of any entry in P1 then a jump is made to P2 and
** P1 is left pointing at the matching entry.
**
** This operation leaves the cursor in a state where it can be
** advanced in the forward direction. The Next instruction will work,
** but not the Prev instruction.
**
** See also: NotFound, NoConflict, NotExists. SeekGe
*/
/* Opcode: NotFound P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** If P4==0 then register P3 holds a blob constructed by MakeRecord. If
** P4>0 then register P3 is the first of P4 registers that form an unpacked
** record.
**
** Cursor P1 is on an index btree. If the record identified by P3 and P4
** is not the prefix of any entry in P1 then a jump is made to P2. If P1
** does contain an entry whose prefix matches the P3/P4 record then control
** falls through to the next instruction and P1 is left pointing at the
** matching entry.
**
** This operation leaves the cursor in a state where it cannot be
** advanced in either direction. In other words, the Next and Prev
** opcodes do not work after this operation.
**
** See also: Found, NotExists, NoConflict, IfNoHope
*/
/* Opcode: IfNoHope P1 P2 P3 P4 *
** Synopsis: key=r[P3@P4]
**
** Register P3 is the first of P4 registers that form an unpacked
** record. Cursor P1 is an index btree. P2 is a jump destination.
** In other words, the operands to this opcode are the same as the
** operands to OP_NotFound and OP_IdxGT.
**
** This opcode is an optimization attempt only. If this opcode always
** falls through, the correct answer is still obtained, but extra work
** is performed.
**
** A value of N in the seekHit flag of cursor P1 means that there exists
** a key P3:N that will match some record in the index. We want to know
** if it is possible for a record P3:P4 to match some record in the
** index. If it is not possible, we can skip some work. So if seekHit
** is less than P4, attempt to find out if a match is possible by running
** OP_NotFound.
**
** This opcode is used in IN clause processing for a multi-column key.
** If an IN clause is attached to an element of the key other than the
** left-most element, and if there are no matches on the most recent
** seek over the whole key, then it might be that one of the key element
**
** If P4==0 then register P3 holds a blob constructed by MakeRecord. If
** P4>0 then register P3 is the first of P4 registers that form an unpacked
** record.
**
** Cursor P1 is on an index btree. If the record identified by P3 and P4
** contains any NULL value, jump immediately to P2. If all terms of the
** record are not-NULL then a check is done to determine if any row in the
** P1 index btree has a matching key prefix. If there are no matches, jump
** immediately to P2. If there is a match, fall through and leave the P1
** cursor pointing to the matching row.
**
** This opcode is similar to OP_NotFound with the exceptions that the
** branch is always taken if any part of the search key input is NULL.
**
** This operation leaves the cursor in a state where it cannot be
** advanced in either direction. In other words, the Next and Prev
** opcodes do not work after this operation.
**
** See also: NotFound, Found, NotExists
*/
case OP_IfNoHope: { /* jump, in3, ncycle */
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
if( pOp->opcode==OP_IfNoHope ){
pC->seekHit = pOp->p4.i;
}
}
break;
}
/* Opcode: SeekRowid P1 P2 P3 * *
** Synopsis: intkey=r[P3]
**
** P1 is the index of a cursor open on an SQL table btree (with integer
** keys). If register P3 does not contain an integer or if P1 does not
** contain a record with rowid P3 then jump immediately to P2.
** Or, if P2 is 0, raise an SQLITE_CORRUPT error. If P1 does contain
** a record with rowid P3 then
** leave the cursor pointing at that record and fall through to the next
** instruction.
**
** The OP_NotExists opcode performs the same operation, but with OP_NotExists
** the P3 register must be guaranteed to contain an integer value. With this
** opcode, register P3 might not contain an integer.
**
** The OP_NotFound opcode performs the same operation on index btrees
** (with arbitrary multi-value keys).
**
** This opcode leaves the cursor in a state where it cannot be advanced
** in either direction. In other words, the Next and Prev opcodes will
** not work following this opcode.
**
** See also: Found, NotFound, NoConflict, SeekRowid
*/
/* Opcode: NotExists P1 P2 P3 * *
** Synopsis: intkey=r[P3]
**
** P1 is the index of a cursor open on an SQL table btree (with integer
** keys). P3 is an integer rowid. If P1 does not contain a record with
** rowid P3 then jump immediately to P2. Or, if P2 is 0, raise an
** SQLITE_CORRUPT error. If P1 does contain a record with rowid P3 then
** leave the cursor pointing at that record and fall through to the next
** instruction.
**
** The OP_SeekRowid opcode performs the same operation but also allows the
** P3 register to contain a non-integer value, in which case the jump is
** always taken. This opcode requires that P3 always contain an integer.
**
** The OP_NotFound opcode performs the same operation on index btrees
** (with arbitrary multi-value keys).
**
** This opcode leaves the cursor in a state where it cannot be advanced
** in either direction. In other words, the Next and Prev opcodes will
** not work following this opcode.
**
** See also: Found, NotFound, NoConflict, SeekRowid
*/
case OP_SeekRowid: { /* jump0, in3, ncycle */
VdbeCursor *pC;
BtCursor *pCrsr;
int res;
u64 iKey;
rc = SQLITE_CORRUPT_BKPT;
}else{
goto jump_to_p2;
}
}
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: Sequence P1 P2 * * *
** Synopsis: r[P2]=cursor[P1].ctr++
**
** 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 */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
assert( p->apCsr[pOp->p1]!=0 );
assert( p->apCsr[pOp->p1]->eCurType!=CURTYPE_VTAB );
pOut = out2Prerelease(p, pOp);
pOut->u.i = p->apCsr[pOp->p1]->seqCount++;
break;
}
/* Opcode: NewRowid P1 P2 P3 * *
** Synopsis: r[P2]=rowid
**
** 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 in the root frame of this VDBE 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,
** an 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 */
pC->deferredMoveto = 0;
pC->cacheStatus = CACHE_STALE;
}
pOut->u.i = v;
break;
}
/* Opcode: Insert P1 P2 P3 P4 P5
** Synopsis: intkey=r[P3] data=r[P2]
**
** 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 MEM_Blob stored in register
** number P2. The key is stored in register P3. The key must
** be a MEM_Int.
**
** 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).
**
** If the OPFLAG_USESEEKRESULT flag of P5 is set, the implementation might
** run faster by avoiding an unnecessary seek on cursor P1. However,
** the OPFLAG_USESEEKRESULT flag must only be set if there have been no prior
** seeks on the cursor or if the most recent seek used a key equal to P3.
**
** If the OPFLAG_ISUPDATE flag is set, then this opcode is part of an
** UPDATE operation. Otherwise (if the flag is clear) then this opcode
** is part of an INSERT operation. The difference is only important to
** the update hook.
**
** Parameter P4 may point to a Table structure, 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; /* MEM cell holding data for the record to be inserted */
Mem *pKey; /* MEM cell holding key for the record */
VdbeCursor *pC; /* Cursor to table into which insert is written */
assert( pTab->aCol!=0 );
db->xUpdateCallback(db->pUpdateArg,
(pOp->p5 & OPFLAG_ISUPDATE) ? SQLITE_UPDATE : SQLITE_INSERT,
zDb, pTab->zName, x.nKey);
}
break;
}
/* Opcode: RowCell P1 P2 P3 * *
**
** P1 and P2 are both open cursors. Both must be opened on the same type
** of table - intkey or index. This opcode is used as part of copying
** the current row from P2 into P1. If the cursors are opened on intkey
** tables, register P3 contains the rowid to use with the new record in
** P1. If they are opened on index tables, P3 is not used.
**
** This opcode must be followed by either an Insert or InsertIdx opcode
** with the OPFLAG_PREFORMAT flag set to complete the insert operation.
*/
case OP_RowCell: {
VdbeCursor *pDest; /* Cursor to write to */
VdbeCursor *pSrc; /* Cursor to read from */
i64 iKey; /* Rowid value to insert with */
pDest = p->apCsr[pOp->p1];
pSrc = p->apCsr[pOp->p2];
iKey = pOp->p3 ? aMem[pOp->p3].u.i : 0;
rc = sqlite3BtreeTransferRow(pDest->uc.pCursor, pSrc->uc.pCursor, iKey);
if( rc!=SQLITE_OK ) goto abort_due_to_error;
break;
};
/* Opcode: Delete P1 P2 P3 P4 P5
**
** Delete the record at which the P1 cursor is currently pointing.
**
** If the OPFLAG_SAVEPOSITION bit of the P5 parameter is set, then
** 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. As a result, in this case
** it is ok to delete a record from within a Next loop. If
** OPFLAG_SAVEPOSITION bit of P5 is clear, then the cursor will be
** left in an undefined state.
**
** If the OPFLAG_AUXDELETE bit is set on P5, that indicates that this
** delete is one of several associated with deleting a table row and
** all its associated index entries. Exactly one of those deletes is
** the "primary" delete. The others are all on OPFLAG_FORDELETE
** cursors or else are marked with the AUXDELETE flag.
**
** If the OPFLAG_NCHANGE (0x01) flag of P2 (NB: P2 not P5) is set, then
** the row change count is incremented (otherwise not).
**
** If the OPFLAG_ISNOOP (0x40) flag of P2 (not P5!) is set, then the
** pre-update-hook for deletes is run, but the btree is otherwise unchanged.
** This happens when the OP_Delete is to be shortly followed by an OP_Insert
** with the same key, causing the btree entry to be overwritten.
**
** P1 must not be pseudo-table. It has to be a real table with
** multiple rows.
**
** If P4 is not NULL then it points to a Table object. In this case either
** the update or pre-update hook, or both, may be invoked. The P1 cursor must
** have been positioned using OP_NotFound prior to invoking this opcode in
** this case. Specifically, if one is configured, the pre-update hook is
** invoked if P4 is not NULL. The update-hook is invoked if one is configured,
** P4 is not NULL, and the OPFLAG_NCHANGE flag is set in P2.
**
** If the OPFLAG_ISUPDATE flag is set in P2, then P3 contains the address
** of the memory cell that contains the value that the rowid of the row will
** be set to by the update.
*/
case OP_Delete: {
assert( pC->uc.pCursor!=0 );
assert( pC->deferredMoveto==0 );
sqlite3VdbeIncrWriteCounter(p, pC);
#ifdef SQLITE_DEBUG
if( pOp->p4type==P4_TABLE
&& HasRowid(pOp->p4.pTab)
&& pOp->p5==0
&& sqlite3BtreeCursorIsValidNN(pC->uc.pCursor)
){
/* If p5 is zero, the seek operation that positioned the cursor prior to
** OP_Delete will have also set the pC->movetoTarget field to the rowid of
** the row that is being deleted */
i64 iKey = sqlite3BtreeIntegerKey(pC->uc.pCursor);
assert( CORRUPT_DB || pC->movetoTarget==iKey );
}
#endif
/* If the update-hook or pre-update-hook will be invoked, set zDb to
** the name of the db to pass as to it. Also set local pTab to a copy
** of p4.pTab. Finally, if p5 is true, indicating that this cursor was
** last moved with OP_Next or OP_Prev, not Seek or NotFound, set
** VdbeCursor.movetoTarget to the current rowid. */
if( pOp->p4type==P4_TABLE && HAS_UPDATE_HOOK(db) ){
assert( pC->iDb>=0 );
assert( pOp->p4.pTab!=0 );
zDb = db->aDb[pC->iDb].zDbSName;
pTab = pOp->p4.pTab;
if( (pOp->p5 & OPFLAG_SAVEPOSITION)!=0 && pC->isTable ){
pC->movetoTarget = sqlite3BtreeIntegerKey(pC->uc.pCursor);
}
*/
case OP_ResetCount: {
sqlite3VdbeSetChanges(db, p->nChange);
p->nChange = 0;
break;
}
/* Opcode: SorterCompare P1 P2 P3 P4
** Synopsis: if key(P1)!=trim(r[P3],P4) goto P2
**
** P1 is a sorter cursor. This instruction compares a prefix of the
** record blob in register P3 against a prefix of the entry that
** the sorter cursor currently points to. Only the first P4 fields
** of r[P3] and the sorter record are compared.
**
** If either P3 or the sorter contains a NULL in one of their significant
** fields (not counting the P4 fields at the end which are ignored) then
** the comparison is assumed to be equal.
**
** Fall through to next instruction if the two records compare equal to
** each other. Jump to P2 if they are different.
*/
case OP_SorterCompare: {
rc = sqlite3VdbeSorterCompare(pC, pIn3, nKeyCol, &res);
VdbeBranchTaken(res!=0,2);
if( rc ) goto abort_due_to_error;
if( res ) goto jump_to_p2;
break;
};
/* Opcode: SorterData P1 P2 P3 * *
** Synopsis: r[P2]=data
**
** Write into register P2 the current sorter data for sorter cursor P1.
** Then clear the column header cache on cursor P3.
**
** This opcode is normally used to move a record out of the sorter and into
** a register that is the source for a pseudo-table cursor created using
** OpenPseudo. That pseudo-table cursor is the one that is identified by
** parameter P3. Clearing the P3 column cache as part of this opcode saves
** us from having to issue a separate NullRow instruction to clear that cache.
*/
case OP_SorterData: { /* ncycle */
VdbeCursor *pC;
pOut = &aMem[pOp->p2];
pC = p->apCsr[pOp->p1];
assert( isSorter(pC) );
rc = sqlite3VdbeSorterRowkey(pC, pOut);
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
if( rc ) goto abort_due_to_error;
p->apCsr[pOp->p3]->cacheStatus = CACHE_STALE;
break;
}
/* Opcode: RowData P1 P2 P3 * *
** Synopsis: r[P2]=data
**
** Write into register P2 the complete row content for the row at
** which cursor P1 is currently pointing.
** 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 cursor P1 is an index, then the content is the key of the row.
** If cursor P2 is a table, then the content extracted is the data.
**
** If the P1 cursor must be pointing to a valid row (not a NULL row)
** of a real table, not a pseudo-table.
**
** If P3!=0 then this opcode is allowed to make an ephemeral pointer
** into the database page. That means that the content of the output
** register will be invalidated as soon as the cursor moves - including
** moves caused by other cursors that "save" the current cursors
** position in order that they can write to the same table. If P3==0
** then a copy of the data is made into memory. P3!=0 is faster, but
** P3==0 is safer.
**
** If P3!=0 then the content of the P2 register is unsuitable for use
** in OP_Result and any OP_Result will invalidate the P2 register content.
** The P2 register content is invalidated by opcodes like OP_Function or
** by any use of another cursor pointing to the same table.
*/
case OP_RowData: {
VdbeCursor *pC;
BtCursor *pCrsr;
u32 n;
pOut = out2Prerelease(p, pOp);
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE );
assert( isSorter(pC)==0 );
assert( pC->nullRow==0 );
assert( pC->uc.pCursor!=0 );
pCrsr = pC->uc.pCursor;
/* The OP_RowData opcodes always follow OP_NotExists or
** OP_SeekRowid or OP_Rewind/Op_Next with no intervening instructions
** that might invalidate the cursor.
** If this where not the case, on of the following assert()s
** would fail. Should this ever change (because of changes in the code
** generator) then the fix would be to insert a call to
** sqlite3VdbeCursorMoveto().
*/
assert( pC->deferredMoveto==0 );
assert( sqlite3BtreeCursorIsValid(pCrsr) );
n = sqlite3BtreePayloadSize(pCrsr);
if( n>(u32)db->aLimit[SQLITE_LIMIT_LENGTH] ){
break;
}
v = sqlite3BtreeIntegerKey(pC->uc.pCursor);
}
pOut->u.i = v;
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.
**
** If cursor P1 is not previously opened, open it now to a special
** pseudo-cursor that always returns NULL for every column.
*/
case OP_NullRow: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pC==0 ){
/* If the cursor is not already open, create a special kind of
** pseudo-cursor that always gives null rows. */
pC = allocateCursor(p, pOp->p1, 1, CURTYPE_PSEUDO);
if( pC==0 ) goto no_mem;
pC->seekResult = 0;
pC->isTable = 1;
pC->noReuse = 1;
pC->uc.pCursor = sqlite3BtreeFakeValidCursor();
}
pC->nullRow = 1;
pC->cacheStatus = CACHE_STALE;
if( pC->eCurType==CURTYPE_BTREE ){
sqlite3BtreeClearCursor(pC->uc.pCursor);
}
#ifdef SQLITE_DEBUG
if( pC->seekOp==0 ) pC->seekOp = OP_NullRow;
#endif
break;
}
/* Opcode: SeekEnd P1 * * * *
**
** Position cursor P1 at the end of the btree for the purpose of
** appending a new entry onto the btree.
**
** It is assumed that the cursor is used only for appending and so
** if the cursor is valid, then the cursor must already be pointing
** at the end of the btree and so no changes are made to
** the cursor.
*/
/* Opcode: Last P1 P2 * * *
**
** The next use of the Rowid or Column or Prev 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.
**
** This opcode leaves the cursor configured to move in reverse order,
** from the end toward the beginning. In other words, the cursor is
** configured to use Prev, not Next.
*/
case OP_SeekEnd: /* ncycle */
case OP_Last: { /* jump0, ncycle */
VdbeCursor *pC;
BtCursor *pCrsr;
int res;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pOp->p2>0 ){
VdbeBranchTaken(res!=0,2);
if( res ) goto jump_to_p2;
}
break;
}
/* Opcode: IfSizeBetween P1 P2 P3 P4 *
**
** Let N be the approximate number of rows in the table or index
** with cursor P1 and let X be 10*log2(N) if N is positive or -1
** if N is zero.
**
** Jump to P2 if X is in between P3 and P4, inclusive.
*/
case OP_IfSizeBetween: { /* jump */
VdbeCursor *pC;
BtCursor *pCrsr;
int res;
i64 sz;
**
** 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, jump immediately to P2.
** If the table or index is not empty, fall through to the following
** instruction.
**
** If P2 is zero, that is an assertion that the P1 table is never
** empty and hence the jump will never be taken.
**
** This opcode leaves the cursor configured to move in forward order,
** from the beginning toward the end. In other words, the cursor is
** configured to use Next, not Prev.
*/
case OP_Rewind: { /* jump0, ncycle */
VdbeCursor *pC;
BtCursor *pCrsr;
int res;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
assert( pOp->p5==0 );
assert( pOp->p2>=0 && pOp->p2<p->nOp );
pC->nullRow = (u8)res;
if( pOp->p2>0 ){
VdbeBranchTaken(res!=0,2);
if( res ) goto jump_to_p2;
}
break;
}
/* Opcode: Next P1 P2 P3 * P5
**
** 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 Next opcode is only valid following an SeekGT, SeekGE, or
** OP_Rewind opcode used to position the cursor. Next is not allowed
** to follow SeekLT, SeekLE, or OP_Last.
**
** The P1 cursor must be for a real table, not a pseudo-table. P1 must have
** been opened prior to this opcode or the program will segfault.
**
** The P3 value is a hint to the btree implementation. If P3==1, that
** means P1 is an SQL index and that this instruction could have been
** omitted if that index had been unique. P3 is usually 0. P3 is
** always either 0 or 1.
**
** If P5 is positive and the jump is taken, then event counter
** number P5-1 in the prepared statement is incremented.
**
** See also: Prev
*/
/* Opcode: Prev P1 P2 P3 * P5
**
** 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 Prev opcode is only valid following an SeekLT, SeekLE, or
** OP_Last opcode used to position the cursor. Prev is not allowed
** to follow SeekGT, SeekGE, or OP_Rewind.
**
** The P1 cursor must be for a real table, not a pseudo-table. If P1 is
** not open then the behavior is undefined.
**
** The P3 value is a hint to the btree implementation. If P3==1, that
** means P1 is an SQL index and that this instruction could have been
** omitted if that index had been unique. P3 is usually 0. P3 is
** always either 0 or 1.
**
** If P5 is positive and the jump is taken, then event counter
** number P5-1 in the prepared statement is incremented.
*/
/* Opcode: SorterNext P1 P2 * * P5
**
** This opcode works just like OP_Next except that P1 must be a
** sorter object for which the OP_SorterSort opcode has been
** invoked. This opcode advances the cursor to the next sorted
** record, or jumps to P2 if there are no more sorted records.
*/
case OP_SorterNext: { /* jump */
VdbeCursor *pC;
pC = p->apCsr[pOp->p1];
assert( isSorter(pC) );
rc = sqlite3VdbeSorterNext(db, pC);
goto next_tail;
** be an optimization.
**
** If P5 has the OPFLAG_APPEND bit set, that is a hint to the b-tree layer
** that this insert is likely to be an append.
**
** If P5 has the OPFLAG_NCHANGE bit set, then the change counter is
** incremented by this instruction. If the OPFLAG_NCHANGE bit is clear,
** then the change counter is unchanged.
**
** If the OPFLAG_USESEEKRESULT flag of P5 is set, the implementation might
** run faster by avoiding an unnecessary seek on cursor P1. However,
** the OPFLAG_USESEEKRESULT flag must only be set if there have been no prior
** seeks on the cursor or if the most recent seek used a key equivalent
** to P2.
**
** This instruction only works for indices. The equivalent instruction
** for tables is OP_Insert.
*/
case OP_IdxInsert: { /* in2 */
VdbeCursor *pC;
BtreePayload x;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
rc = sqlite3VdbeSorterWrite(pC, pIn2);
if( rc) goto abort_due_to_error;
break;
}
/* Opcode: IdxDelete P1 P2 P3 * P5
** Synopsis: key=r[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.
**
** If P5 is not zero, then raise an SQLITE_CORRUPT_INDEX error
** if no matching index entry is found. This happens when running
** an UPDATE or DELETE statement and the index entry to be updated
** or deleted is not found. For some uses of IdxDelete
** (example: the EXCEPT operator) it does not matter that no matching
** entry is found. For those cases, P5 is zero. Also, do not raise
** this (self-correcting and non-critical) error if in writable_schema mode.
*/
case OP_IdxDelete: {
}
assert( pC->deferredMoveto==0 );
pC->cacheStatus = CACHE_STALE;
pC->seekResult = 0;
break;
}
/* Opcode: DeferredSeek P1 * P3 P4 *
** Synopsis: Move P3 to P1.rowid if needed
**
** P1 is an open index cursor and P3 is a cursor on the corresponding
** table. This opcode does a deferred seek of the P3 table cursor
** to the row that corresponds to the current row of P1.
**
** This is a deferred seek. Nothing actually happens until
** the cursor is used to read a record. That way, if no reads
** occur, no unnecessary I/O happens.
**
** P4 may be an array of integers (type P4_INTARRAY) containing
** one entry for each column in the P3 table. If array entry a(i)
** is non-zero, then reading column a(i)-1 from cursor P3 is
** equivalent to performing the deferred seek and then reading column i
** from P1. This information is stored in P3 and used to redirect
** reads against P3 over to P1, thus possibly avoiding the need to
** seek and read cursor P3.
*/
/* Opcode: IdxRowid P1 P2 * * *
** Synopsis: r[P2]=rowid
**
** 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, MakeRecord.
*/
case OP_DeferredSeek: /* ncycle */
case OP_IdxRowid: { /* out2, ncycle */
VdbeCursor *pC; /* The P1 index cursor */
VdbeCursor *pTabCur; /* The P2 table cursor (OP_DeferredSeek only) */
i64 rowid; /* Rowid that P1 current points to */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE || IsNullCursor(pC) );
assert( pC->uc.pCursor!=0 );
assert( pC->isTable==0 || IsNullCursor(pC) );
assert( pC->deferredMoveto==0 );
assert( !pC->nullRow || pOp->opcode==OP_IdxRowid );
/* The IdxRowid and Seek opcodes are combined because of the commonality
** of sqlite3VdbeCursorRestore() and sqlite3VdbeIdxRowid(). */
rc = sqlite3VdbeCursorRestore(pC);
/* sqlite3VdbeCursorRestore() may fail if the cursor has been disturbed
** since it was last positioned and an error (e.g. OOM or an IO error)
** occurs while trying to reposition it. */
if( rc!=SQLITE_OK ) goto abort_due_to_error;
if( !pC->nullRow ){
rowid = 0; /* Not needed. Only used to silence a warning. */
rc = sqlite3VdbeIdxRowid(db, pC->uc.pCursor, &rowid);
if( rc!=SQLITE_OK ){
goto abort_due_to_error;
}
}
}else{
assert( pOp->opcode==OP_IdxRowid );
sqlite3VdbeMemSetNull(&aMem[pOp->p2]);
}
break;
}
/* Opcode: FinishSeek P1 * * * *
**
** If cursor P1 was previously moved via OP_DeferredSeek, complete that
** seek operation now, without further delay. If the cursor seek has
** already occurred, this instruction is a no-op.
*/
case OP_FinishSeek: { /* ncycle */
VdbeCursor *pC; /* The P1 index cursor */
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
if( pC->deferredMoveto ){
rc = sqlite3VdbeFinishMoveto(pC);
if( rc ) goto abort_due_to_error;
}
break;
}
** 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
** value of the root page that moved - its value before the move occurred -
** is stored in register P2. If no page movement was required (because the
** table being dropped was already the last one in the database) then a
** zero is stored in register P2. If AUTOVACUUM is disabled then a zero
** is stored in register P2.
**
** This opcode throws an error if there are any active reader VMs when
** it is invoked. This is done to avoid the difficulty associated with
** updating existing cursors when a root page is moved in an AUTOVACUUM
** database. This error is thrown even if the database is not an AUTOVACUUM
** db in order to avoid introducing an incompatibility between autovacuum
** and non-autovacuum modes.
**
** See also: Clear
*/
case OP_Destroy: { /* out2 */
int iMoved;
int iDb;
aMem[pOp->p3].u.i += nChange;
}
}
if( rc ) goto abort_due_to_error;
break;
}
/* Opcode: ResetSorter P1 * * * *
**
** Delete all contents from the ephemeral table or sorter
** that is open on cursor P1.
**
** This opcode only works for cursors used for sorting and
** opened with OP_OpenEphemeral or OP_SorterOpen.
*/
case OP_ResetSorter: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
if( isSorter(pC) ){
sqlite3VdbeSorterReset(db, pC->uc.pSorter);
goto abort_due_to_error;
}
/* Register pRt is used to store the memory required to save the state
** of the current program, and the memory required at runtime to execute
** the trigger program. If this trigger has been fired before, then pRt
** is already allocated. Otherwise, it must be initialized. */
if( (pRt->flags&MEM_Blob)==0 ){
/* SubProgram.nMem is set to the number of memory cells used by the
** program stored in SubProgram.aOp. As well as these, one memory
** cell is required for each cursor used by the program. Set local
** variable nMem (and later, VdbeFrame.nChildMem) to this value.
*/
nMem = pProgram->nMem + pProgram->nCsr;
assert( nMem>0 );
if( pProgram->nCsr==0 ) nMem++;
nByte = ROUND8(sizeof(VdbeFrame))
+ nMem * sizeof(Mem)
+ pProgram->nCsr * sizeof(VdbeCursor*)
+ (pProgram->nOp + 7)/8;
pFrame = sqlite3DbMallocZero(db, nByte);
if( !pOp->p1 ){
sqlite3ExpirePreparedStatements(db, pOp->p2);
}else{
p->expired = pOp->p2+1;
}
break;
}
/* Opcode: CursorLock P1 * * * *
**
** Lock the btree to which cursor P1 is pointing so that the btree cannot be
** written by an other cursor.
*/
case OP_CursorLock: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE );
sqlite3BtreeCursorPin(pC->uc.pCursor);
break;
}
/* Opcode: CursorUnlock P1 * * * *
**
** Unlock the btree to which cursor P1 is pointing so that it can be
** written by other cursors.
*/
case OP_CursorUnlock: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
pC = p->apCsr[pOp->p1];
assert( pC!=0 );
assert( pC->eCurType==CURTYPE_BTREE );
sqlite3BtreeCursorUnpin(pC->uc.pCursor);
break;
}
assert( p->errorAction==OE_Abort && p->usesStmtJournal );
if( rc ) goto abort_due_to_error;
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: { /* ncycle */
VdbeCursor *pCur;
sqlite3_vtab_cursor *pVCur;
sqlite3_vtab *pVtab;
const sqlite3_module *pModule;
assert( p->bIsReader );
pCur = 0;
pVCur = 0;
pVtab = pOp->p4.pVtab->pVtab;
if( pVtab==0 || NEVER(pVtab->pModule==0) ){
rc = SQLITE_LOCKED;
goto abort_due_to_error;
}
pModule = pVtab->pModule;
rc = pModule->xOpen(pVtab, &pVCur);
sqlite3VtabImportErrmsg(p, pVtab);
if( rc ) goto abort_due_to_error;
/* Initialize sqlite3_vtab_cursor base class */
pVCur->pVtab = pVtab;
/* Initialize vdbe cursor object */
pCur = allocateCursor(p, pOp->p1, 0, CURTYPE_VTAB);
if( pCur ){
pCur->uc.pVCur = pVCur;
pVtab->nRef++;
}else{
assert( db->mallocFailed );
pModule->xClose(pVCur);
goto no_mem;
}
break;
sqlite3VdbeMemSetStr(pOut, zErr, -1, SQLITE_UTF8, sqlite3_free);
}
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VInitIn P1 P2 P3 * *
** Synopsis: r[P2]=ValueList(P1,P3)
**
** Set register P2 to be a pointer to a ValueList object for cursor P1
** with cache register P3 and output register P3+1. This ValueList object
** can be used as the first argument to sqlite3_vtab_in_first() and
** sqlite3_vtab_in_next() to extract all of the values stored in the P1
** cursor. Register P3 is used to hold the values returned by
** sqlite3_vtab_in_first() and sqlite3_vtab_in_next().
*/
case OP_VInitIn: { /* out2, ncycle */
VdbeCursor *pC; /* The cursor containing the RHS values */
ValueList *pRhs; /* New ValueList object to put in reg[P2] */
pC = p->apCsr[pOp->p1];
pRhs = sqlite3_malloc64( sizeof(*pRhs) );
if( pRhs==0 ) goto no_mem;
pRhs->pCsr = pC->uc.pCursor;
pRhs->pOut = &aMem[pOp->p3];
pOut = out2Prerelease(p, pOp);
pOut->flags = MEM_Null;
sqlite3VdbeMemSetPointer(pOut, pRhs, "ValueList", sqlite3VdbeValueListFree);
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VFilter P1 P2 P3 P4 *
** Synopsis: iplan=r[P3] zplan='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
** 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, ncycle */
int nArg;
int iQuery;
const sqlite3_module *pModule;
Mem *pQuery;
Mem *pArgc;
sqlite3_vtab_cursor *pVCur;
sqlite3_vtab *pVtab;
VdbeCursor *pCur;
int res;
int i;
Mem **apArg;
pQuery = &aMem[pOp->p3];
pArgc = &pQuery[1];
pCur = p->apCsr[pOp->p1];
assert( memIsValid(pQuery) );
if( res ) goto jump_to_p2;
break;
}
#endif /* SQLITE_OMIT_VIRTUALTABLE */
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Opcode: VColumn P1 P2 P3 * P5
** Synopsis: r[P3]=vcolumn(P2)
**
** Store in register P3 the value of the P2-th column of
** the current row of the virtual-table of cursor P1.
**
** If the VColumn opcode is being used to fetch the value of
** an unchanging column during an UPDATE operation, then the P5
** value is OPFLAG_NOCHNG. This will cause the sqlite3_vtab_nochange()
** function to return true inside the xColumn method of the virtual
** table implementation. The P5 column might also contain other
** bits (OPFLAG_LENGTHARG or OPFLAG_TYPEOFARG) but those bits are
** unused by OP_VColumn.
*/
case OP_VColumn: { /* ncycle */
break;
}
pVtab = pCur->uc.pVCur->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.
*/
rc = pModule->xNext(pCur->uc.pVCur);
sqlite3VtabImportErrmsg(p, pVtab);
if( rc ) goto abort_due_to_error;
res = pModule->xEof(pCur->uc.pVCur);
VdbeBranchTaken(!res,2);
if( !res ){
/* If there is data, jump to P2 */
goto jump_to_p2_and_check_for_interrupt;
}
pOp->p1 = 0;
}
pOp->p1++;
p->aCounter[SQLITE_STMTSTATUS_RUN]++;
goto jump_to_p2;
}
#ifdef SQLITE_ENABLE_CURSOR_HINTS
/* Opcode: CursorHint P1 * * P4 *
**
** Provide a hint to cursor P1 that it only needs to return rows that
** satisfy the Expr in P4. TK_REGISTER terms in the P4 expression refer
** to values currently held in registers. TK_COLUMN terms in the P4
** expression refer to columns in the b-tree to which cursor P1 is pointing.
*/
case OP_CursorHint: {
VdbeCursor *pC;
assert( pOp->p1>=0 && pOp->p1<p->nCursor );
assert( pOp->p4type==P4_EXPR );
pC = p->apCsr[pOp->p1];
if( pC ){
assert( pC->eCurType==CURTYPE_BTREE );
sqlite3BtreeCursorHint(pC->uc.pCursor, BTREE_HINT_RANGE,
/* #include "vdbeInt.h" */
#ifndef SQLITE_OMIT_INCRBLOB
/*
** Valid sqlite3_blob* handles point to Incrblob structures.
*/
typedef struct Incrblob Incrblob;
struct Incrblob {
int nByte; /* Size of open blob, in bytes */
int iOffset; /* Byte offset of blob in cursor data */
u16 iCol; /* Table column this handle is open on */
BtCursor *pCsr; /* Cursor pointing at blob row */
sqlite3_stmt *pStmt; /* Statement holding cursor open */
sqlite3 *db; /* The associated database */
char *zDb; /* Database name */
Table *pTab; /* Table object */
};
/*
** This function is used by both blob_open() and blob_reopen(). It seeks
** the b-tree cursor associated with blob handle p to point to row iRow.
** If successful, SQLITE_OK is returned and subsequent calls to
** sqlite3_blob_read() or sqlite3_blob_write() access the specified row.
**
** If an error occurs, or if the specified row does not exist or does not
** contain a value of type TEXT or BLOB in the column nominated when the
** blob handle was opened, then an error code is returned and *pzErr may
** be set to point to a buffer containing an error message. It is the
** responsibility of the caller to free the error message buffer using
** sqlite3DbFree().
**
** If an error does occur, then the b-tree cursor is closed. All subsequent
** calls to sqlite3_blob_read(), blob_write() or blob_reopen() will
** immediately return SQLITE_ABORT.
*/
static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){
int rc; /* Error code */
char *zErr = 0; /* Error message */
Vdbe *v = (Vdbe *)p->pStmt;
/* Set the value of register r[1] in the SQL statement to integer iRow.
** This is done directly as a performance optimization
rc = SQLITE_ERROR;
sqlite3BtreeLeaveAll(db);
goto blob_open_out;
}
}
pBlob->pStmt = (sqlite3_stmt *)sqlite3VdbeCreate(&sParse);
assert( pBlob->pStmt || db->mallocFailed );
if( pBlob->pStmt ){
/* 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 int iLn = VDBE_OFFSET_LINENO(2);
static const VdbeOpList openBlob[] = {
{OP_TableLock, 0, 0, 0}, /* 0: Acquire a read or write lock */
{OP_OpenRead, 0, 0, 0}, /* 1: Open a cursor */
/* blobSeekToRow() will initialize r[1] to the desired rowid */
{OP_NotExists, 0, 5, 1}, /* 2: Seek the cursor to rowid=r[1] */
{OP_Column, 0, 0, 1}, /* 3 */
{OP_ResultRow, 1, 0, 0}, /* 4 */
{OP_Halt, 0, 0, 0}, /* 5 */
};
Vdbe *v = (Vdbe *)pBlob->pStmt;
int iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
VdbeOp *aOp;
sqlite3VdbeAddOp4Int(v, OP_Transaction, iDb, wrFlag,
pTab->pSchema->schema_cookie,
}
if( db->mallocFailed==0 ){
#endif
/* Remove either the OP_OpenWrite or OpenRead. Set the P2
** parameter of the other to pTab->tnum. */
if( wrFlag ) aOp[1].opcode = OP_OpenWrite;
aOp[1].p2 = pTab->tnum;
aOp[1].p3 = iDb;
/* Configure the number of columns. 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.
*/
aOp[1].p4type = P4_INT32;
aOp[1].p4.i = pTab->nCol+1;
aOp[3].p2 = pTab->nCol;
sParse.nVar = 0;
sParse.nMem = 1;
sParse.nTab = 1;
sqlite3VdbeMakeReady(v, &sParse);
rc = SQLITE_ABORT;
}else{
/* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is
** returned, clean-up the statement handle.
*/
assert( db == v->db );
sqlite3BtreeEnterCursor(p->pCsr);
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
if( xCall==sqlite3BtreePutData && db->xPreUpdateCallback ){
/* If a pre-update hook is registered and this is a write cursor,
** invoke it here.
**
** TODO: The preupdate-hook is passed SQLITE_DELETE, even though this
** operation should really be an SQLITE_UPDATE. This is probably
** incorrect, but is convenient because at this point the new.* values
** are not easily obtainable. And for the sessions module, an
** SQLITE_UPDATE where the PK columns do not change is handled in the
** same way as an SQLITE_DELETE (the SQLITE_DELETE code is actually
** slightly more efficient). Since you cannot write to a PK column
** using the incremental-blob API, this works. For the sessions module
**
** sqlite3VdbeSorterWrite() Add a single new row to the VdbeSorter
** object. The row is a binary blob in the
** OP_MakeRecord format that contains both
** the ORDER BY key columns and result columns
** in the case of a SELECT w/ ORDER BY, or
** the complete record for an index entry
** in the case of a CREATE INDEX.
**
** sqlite3VdbeSorterRewind() Sort all content previously added.
** Position the read cursor on the
** first sorted element.
**
** sqlite3VdbeSorterNext() Advance the read cursor to the next sorted
** element.
**
** sqlite3VdbeSorterRowkey() Return the complete binary blob for the
** row currently under the read cursor.
**
** sqlite3VdbeSorterCompare() Compare the binary blob for the row
** currently under the read cursor against
** another binary blob X and report if
** X is strictly less than the read cursor.
** Used to enforce uniqueness in a
** CREATE UNIQUE INDEX statement.
**
** sqlite3VdbeSorterClose() Close the VdbeSorter object and reclaim
** all resources.
**
** sqlite3VdbeSorterReset() Refurbish the VdbeSorter for reuse. This
** is like Close() followed by Init() only
** much faster.
**
UnpackedRecord *pUnpacked; /* Space to unpack a record */
SorterList list; /* List for thread to write to a PMA */
SorterCompare xCompare; /* Compare function to use */
SorterFile file; /* Temp file for level-0 PMAs */
SorterFile file2; /* Space for other PMAs */
};
/*
** Main sorter structure. A single instance of this is allocated for each
** sorter cursor created by the VDBE.
**
** mxKeysize:
** As records are added to the sorter by calls to sqlite3VdbeSorterWrite(),
** this variable is updated so as to be set to the size on disk of the
** largest record in the sorter.
*/
struct VdbeSorter {
int mnPmaSize; /* Minimum PMA size, in bytes */
int mxPmaSize; /* Maximum PMA size, in bytes. 0==no limit */
int mxKeysize; /* Largest serialized key seen so far */
return rc;
}
/*
** Attach PmaReader pReadr to file pFile (if it is not already attached to
** that file) and seek it to offset iOff within the file. Return SQLITE_OK
** if successful, or an SQLite error code if an error occurs.
*/
static int vdbePmaReaderSeek(
SortSubtask *pTask, /* Task context */
PmaReader *pReadr, /* Reader whose cursor is to be moved */
SorterFile *pFile, /* Sorter file to read from */
i64 iOff /* Offset in pFile */
){
int rc = SQLITE_OK;
assert( pReadr->pIncr==0 || pReadr->pIncr->bEof==0 );
if( sqlite3FaultSim(201) ) return SQLITE_IOERR_READ;
if( pReadr->aMap ){
sqlite3OsUnfetch(pReadr->pFd, 0, pReadr->aMap);
}
}else if( pTask->pSorter->pKeyInfo->aSortFlags[0] ){
assert( !(pTask->pSorter->pKeyInfo->aSortFlags[0]&KEYINFO_ORDER_BIGNULL) );
res = res * -1;
}
return res;
}
/*
** Initialize the temporary index cursor just opened as a sorter cursor.
**
** Usually, the sorter module uses the value of (pCsr->pKeyInfo->nKeyField)
** to determine the number of fields that should be compared from the
** records being sorted. However, if the value passed as argument nField
** is non-zero and the sorter is able to guarantee a stable sort, nField
** is used instead. This is used when sorting records for a CREATE INDEX
** statement. In this case, keys are always delivered to the sorter in
** order of the primary key, which happens to be make up the final part
** of the records being sorted. So if the sort is stable, there is never
** any reason to compare PK fields and they can be ignored for a small
if( pIncr->aFile[0].pFd ) sqlite3OsCloseFree(pIncr->aFile[0].pFd);
if( pIncr->aFile[1].pFd ) sqlite3OsCloseFree(pIncr->aFile[1].pFd);
}
#endif
vdbeMergeEngineFree(pIncr->pMerger);
sqlite3_free(pIncr);
}
}
/*
** Reset a sorting cursor back to its original empty state.
*/
SQLITE_PRIVATE void sqlite3VdbeSorterReset(sqlite3 *db, VdbeSorter *pSorter){
int i;
(void)vdbeSorterJoinAll(pSorter, SQLITE_OK);
assert( pSorter->bUseThreads || pSorter->pReader==0 );
#if SQLITE_MAX_WORKER_THREADS>0
if( pSorter->pReader ){
vdbePmaReaderClear(pSorter->pReader);
sqlite3DbFree(db, pSorter->pReader);
pSorter->pReader = 0;
pSorter->list.pList = 0;
pSorter->list.szPMA = 0;
pSorter->bUsePMA = 0;
pSorter->iMemory = 0;
pSorter->mxKeysize = 0;
sqlite3DbFree(db, pSorter->pUnpacked);
pSorter->pUnpacked = 0;
}
/*
** Free any cursor components allocated by sqlite3VdbeSorterXXX routines.
*/
SQLITE_PRIVATE void sqlite3VdbeSorterClose(sqlite3 *db, VdbeCursor *pCsr){
VdbeSorter *pSorter;
assert( pCsr->eCurType==CURTYPE_SORTER );
pSorter = pCsr->uc.pSorter;
if( pSorter ){
sqlite3VdbeSorterReset(db, pSorter);
sqlite3_free(pSorter->list.aMemory);
sqlite3DbFree(db, pSorter);
pCsr->uc.pSorter = 0;
}
return rc;
#endif /* SQLITE_MAX_WORKER_THREADS!=0 */
}
/*
** Add a record to the sorter.
*/
SQLITE_PRIVATE int sqlite3VdbeSorterWrite(
const VdbeCursor *pCsr, /* Sorter cursor */
Mem *pVal /* Memory cell containing record */
){
VdbeSorter *pSorter;
int rc = SQLITE_OK; /* Return Code */
SorterRecord *pNew; /* New list element */
int bFlush; /* True to flush contents of memory to PMA */
i64 nReq; /* Bytes of memory required */
i64 nPMA; /* Bytes of PMA space required */
int t; /* serial type of first record field */
** that has already written two or more level-0 PMAs to one or more temp
** files. It builds a tree of MergeEngine/IncrMerger/PmaReader objects that
** can be used to incrementally merge all PMAs on disk.
**
** If successful, SQLITE_OK is returned and *ppOut set to point to the
** MergeEngine object at the root of the tree before returning. Or, if an
** error occurs, an SQLite error code is returned and the final value
** of *ppOut is undefined.
*/
static int vdbeSorterMergeTreeBuild(
VdbeSorter *pSorter, /* The VDBE cursor that implements the sort */
MergeEngine **ppOut /* Write the MergeEngine here */
){
MergeEngine *pMain = 0;
int rc = SQLITE_OK;
int iTask;
#if SQLITE_MAX_WORKER_THREADS>0
/* If the sorter uses more than one task, then create the top-level
** MergeEngine here. This MergeEngine will read data from exactly
** one PmaReader per sub-task. */
return SQLITE_NOMEM_BKPT;
}
pOut->n = nKey;
MemSetTypeFlag(pOut, MEM_Blob);
memcpy(pOut->z, pKey, nKey);
return SQLITE_OK;
}
/*
** Compare the key in memory cell pVal with the key that the sorter cursor
** passed as the first argument currently points to. For the purposes of
** the comparison, ignore the rowid field at the end of each record.
**
** If the sorter cursor key contains any NULL values, consider it to be
** less than pVal. Even if pVal also contains NULL values.
**
** If an error occurs, return an SQLite error code (i.e. SQLITE_NOMEM).
** Otherwise, set *pRes to a negative, zero or positive value if the
** key in pVal is smaller than, equal to or larger than the current sorter
** key.
**
** This routine forms the core of the OP_SorterCompare opcode, which in
** turn is used to verify uniqueness when constructing a UNIQUE INDEX.
*/
SQLITE_PRIVATE int sqlite3VdbeSorterCompare(
const VdbeCursor *pCsr, /* Sorter cursor */
Mem *pVal, /* Value to compare to current sorter key */
int nKeyCol, /* Compare this many columns */
int *pRes /* OUT: Result of comparison */
){
VdbeSorter *pSorter;
UnpackedRecord *r2;
KeyInfo *pKeyInfo;
int i;
void *pKey; int nKey; /* Sorter key to compare pVal with */
/* An instance of the bytecode() table-valued function.
*/
typedef struct bytecodevtab bytecodevtab;
struct bytecodevtab {
sqlite3_vtab base; /* Base class - must be first */
sqlite3 *db; /* Database connection */
int bTablesUsed; /* 2 for tables_used(). 0 for bytecode(). */
};
/* A cursor for scanning through the bytecode
*/
typedef struct bytecodevtab_cursor bytecodevtab_cursor;
struct bytecodevtab_cursor {
sqlite3_vtab_cursor base; /* Base class - must be first */
sqlite3_stmt *pStmt; /* The statement whose bytecode is displayed */
int iRowid; /* The rowid of the output table */
int iAddr; /* Address */
int needFinalize; /* Cursors owns pStmt and must finalize it */
int showSubprograms; /* Provide a listing of subprograms */
Op *aOp; /* Operand array */
char *zP4; /* Rendered P4 value */
const char *zType; /* tables_used.type */
const char *zSchema; /* tables_used.schema */
const char *zName; /* tables_used.name */
/*
** This method is the destructor for bytecodevtab objects.
*/
static int bytecodevtabDisconnect(sqlite3_vtab *pVtab){
bytecodevtab *p = (bytecodevtab*)pVtab;
sqlite3_free(p);
return SQLITE_OK;
}
/*
** Constructor for a new bytecodevtab_cursor object.
*/
static int bytecodevtabOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
bytecodevtab *pVTab = (bytecodevtab*)p;
bytecodevtab_cursor *pCur;
pCur = sqlite3_malloc( sizeof(*pCur) );
if( pCur==0 ) return SQLITE_NOMEM;
memset(pCur, 0, sizeof(*pCur));
sqlite3VdbeMemInit(&pCur->sub, pVTab->db, 1);
*ppCursor = &pCur->base;
return SQLITE_OK;
}
/*
** Clear all internal content from a bytecodevtab cursor.
*/
static void bytecodevtabCursorClear(bytecodevtab_cursor *pCur){
sqlite3_free(pCur->zP4);
pCur->zP4 = 0;
sqlite3VdbeMemRelease(&pCur->sub);
sqlite3VdbeMemSetNull(&pCur->sub);
if( pCur->needFinalize ){
sqlite3_finalize(pCur->pStmt);
}
pCur->pStmt = 0;
pCur->needFinalize = 0;
pCur->zType = 0;
pCur->zSchema = 0;
pCur->zName = 0;
}
/*
** Destructor for a bytecodevtab_cursor.
*/
static int bytecodevtabClose(sqlite3_vtab_cursor *cur){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
bytecodevtabCursorClear(pCur);
sqlite3_free(pCur);
return SQLITE_OK;
}
/*
** Advance a bytecodevtab_cursor to its next row of output.
*/
static int bytecodevtabNext(sqlite3_vtab_cursor *cur){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
bytecodevtab *pTab = (bytecodevtab*)cur->pVtab;
int rc;
if( pCur->zP4 ){
sqlite3_free(pCur->zP4);
pCur->zP4 = 0;
}
if( pCur->zName ){
pCur->zName = 0;
pCur->zType = 0;
pCur->zSchema = 0;
&pCur->iAddr,
&pCur->aOp);
if( rc!=SQLITE_OK ){
sqlite3VdbeMemSetNull(&pCur->sub);
pCur->aOp = 0;
}
return SQLITE_OK;
}
/*
** Return TRUE if the cursor has been moved off of the last
** row of output.
*/
static int bytecodevtabEof(sqlite3_vtab_cursor *cur){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
return pCur->aOp==0;
}
/*
** Return values of columns for the row at which the bytecodevtab_cursor
** is currently pointing.
*/
static int bytecodevtabColumn(
sqlite3_vtab_cursor *cur, /* The cursor */
sqlite3_context *ctx, /* First argument to sqlite3_result_...() */
int i /* Which column to return */
){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
bytecodevtab *pVTab = (bytecodevtab*)cur->pVtab;
Op *pOp = pCur->aOp + pCur->iAddr;
if( pVTab->bTablesUsed ){
if( i==4 ){
i = 8;
}else{
if( i<=2 && pCur->zType==0 ){
Schema *pSchema;
HashElem *k;
int iDb = pOp->p3;
sqlite3_result_int(ctx, pOp->opcode==OP_OpenWrite);
break;
}
return SQLITE_OK;
}
/*
** Return the rowid for the current row. In this implementation, the
** rowid is the same as the output value.
*/
static int bytecodevtabRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor*)cur;
*pRowid = pCur->iRowid;
return SQLITE_OK;
}
/*
** Initialize a cursor.
**
** idxNum==0 means show all subprograms
** idxNum==1 means show only the main bytecode and omit subprograms.
*/
static int bytecodevtabFilter(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
bytecodevtab_cursor *pCur = (bytecodevtab_cursor *)pVtabCursor;
bytecodevtab *pVTab = (bytecodevtab *)pVtabCursor->pVtab;
int rc = SQLITE_OK;
(void)idxStr;
bytecodevtabCursorClear(pCur);
pCur->iRowid = 0;
pCur->iAddr = 0;
pCur->showSubprograms = idxNum==0;
assert( argc==1 );
if( sqlite3_value_type(argv[0])==SQLITE_TEXT ){
*/
#define MEMJOURNAL_DFLT_FILECHUNKSIZE 1024
/*
** For chunk size nChunkSize, return the number of bytes that should
** be allocated for each FileChunk structure.
*/
#define fileChunkSize(nChunkSize) (sizeof(FileChunk) + ((nChunkSize)-8))
/*
** An instance of this object serves as a cursor into the rollback journal.
** The cursor can be either for reading or writing.
*/
struct FilePoint {
sqlite3_int64 iOffset; /* Offset from the beginning of the file */
FileChunk *pChunk; /* Specific chunk into which cursor points */
};
/*
** This structure is a subclass of sqlite3_file. Each open memory-journal
** is an instance of this class.
*/
struct MemJournal {
const sqlite3_io_methods *pMethod; /* Parent class. MUST BE FIRST */
int nChunkSize; /* In-memory chunk-size */
}
/*
** 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 X
** (even if X is implied).
** pExpr->iTable Set to the cursor number for the table obtained
** from pSrcList.
** pExpr->y.pTab Points to the Table structure of X.Y (even if
** X and/or Y are implied.)
** 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 zDb variable 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
** Y: The name of a table in a FROM clause. Or in a trigger
** one of the special names "old" or "new".
**
** Z: The name of a column in table Y.
**
** The node at the root of the subtree is modified as follows:
**
** Expr.op Changed to TK_COLUMN
** Expr.pTab Points to the Table object for X.Y
** Expr.iColumn The column index in X.Y. -1 for the rowid.
** Expr.iTable The VDBE cursor number for X.Y
**
**
** To resolve result-set references, look for expression nodes of the
** form Z (with no X and Y prefix) where the Z matches the right-hand
** size of an AS clause in the result-set of a SELECT. The Z expression
** is replaced by a copy of the left-hand side of the result-set expression.
** Table-name and function resolution occurs on the substituted expression
** tree. For example, in:
**
** SELECT a+b AS x, c+d AS y FROM t1 ORDER BY x;
** column of the vector (numbered starting with 0). The caller must
** ensure that i is within range.
**
** If pVector is really a scalar (and "scalar" here includes subqueries
** that return a single column!) then return pVector unmodified.
**
** pVector retains ownership of the returned subexpression.
**
** If the vector is a (SELECT ...) then the expression returned is
** just the expression for the i-th term of the result set, and may
** not be ready for evaluation because the table cursor has not yet
** been positioned.
*/
SQLITE_PRIVATE Expr *sqlite3VectorFieldSubexpr(Expr *pVector, int i){
assert( i<sqlite3ExprVectorSize(pVector) || pVector->op==TK_ERROR );
if( sqlite3ExprIsVector(pVector) ){
assert( pVector->op2==0 || pVector->op==TK_REGISTER );
if( pVector->op==TK_SELECT || pVector->op2==TK_SELECT ){
assert( ExprUseXSelect(pVector) );
return pVector->x.pSelect->pEList->a[i].pExpr;
}else{
}
pItem->zEName = sqlite3DbStrDup(db, pOldItem->zEName);
pItem->fg = pOldItem->fg;
pItem->fg.done = 0;
pItem->u = pOldItem->u;
}
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, const SrcList *p, int flags){
SrcList *pNew;
int i;
int nByte;
assert( pWalker->eCode==3 || pWalker->eCode==0 );
if( (pSelect->selFlags & SF_Correlated)!=0 ){
pWalker->eCode = 0;
return WRC_Abort;
}
return WRC_Prune;
}
/*
** Walk an expression tree. Return non-zero if the expression is constant
** for any single row of the table with cursor iCur. In other words, the
** expression must not refer to any non-deterministic function nor any
** table other than iCur.
**
** Consider uncorrelated subqueries to be constants if the bAllowSubq
** parameter is true.
*/
static int sqlite3ExprIsTableConstant(Expr *p, int iCur, int bAllowSubq){
Walker w;
w.eCode = 3;
w.pParse = 0;
/*
** This function is used by the implementation of the IN (...) operator.
** The pX parameter is the expression on the RHS of the IN operator, which
** might be either a list of expressions or a subquery.
**
** The job of this routine is to find or create a b-tree object that can
** be used either to test for membership in the RHS set or to iterate through
** all members of the RHS set, skipping duplicates.
**
** A cursor is opened on the b-tree object that is the RHS of the IN operator
** and the *piTab parameter is set to the index of that cursor.
**
** The returned value of this function indicates the b-tree type, as follows:
**
** IN_INDEX_ROWID - The cursor was opened on a database table.
** IN_INDEX_INDEX_ASC - The cursor was opened on an ascending index.
** IN_INDEX_INDEX_DESC - The cursor was opened on a descending index.
** IN_INDEX_EPH - The cursor was opened on a specially created and
** populated ephemeral table.
** IN_INDEX_NOOP - No cursor was allocated. The IN operator must be
** implemented as a sequence of comparisons.
**
** An existing b-tree might be used if the RHS expression pX is a simple
** subquery such as:
**
** SELECT <column1>, <column2>... FROM <table>
**
** If the RHS of the IN operator is a list or a more complex subquery, then
** an ephemeral table might need to be generated from the RHS and then
** pX->iTable made to point to the ephemeral table instead of an
** and the RHS of the IN operator is a list, not a subquery
** and the RHS is not constant or has two or fewer terms,
** then it is not worth creating an ephemeral table to evaluate
** the IN operator so return IN_INDEX_NOOP.
*/
if( eType==0
&& (inFlags & IN_INDEX_NOOP_OK)
&& ExprUseXList(pX)
&& (!sqlite3InRhsIsConstant(pParse,pX) || pX->x.pList->nExpr<=2)
){
pParse->nTab--; /* Back out the allocation of the unused cursor */
iTab = -1; /* Cursor is not allocated */
eType = IN_INDEX_NOOP;
}
if( eType==0 ){
/* Could not find an existing table or index to use as the RHS b-tree.
** We will have to generate an ephemeral table to do the job.
*/
u32 savedNQueryLoop = pParse->nQueryLoop;
int rMayHaveNull = 0;
#ifndef SQLITE_OMIT_SUBQUERY
/*
** Generate code that will construct an ephemeral table containing all terms
** in the RHS of an IN operator. The IN operator can be in either of two
** forms:
**
** x IN (4,5,11) -- IN operator with list on right-hand side
** x IN (SELECT a FROM b) -- IN operator with subquery on the right
**
** The pExpr parameter is the IN operator. The cursor number for the
** constructed ephemeral table is returned. The first time the ephemeral
** table is computed, the cursor number is also stored in pExpr->iTable,
** however the cursor number returned might not be the same, as it might
** have been duplicated using OP_OpenDup.
**
** If the LHS expression ("x" in the examples) is a column value, or
** the SELECT statement returns a column value, then the affinity of that
** column is used to build the index keys. If both 'x' and the
** SELECT... statement are columns, then numeric affinity is used
** if either column has NUMERIC or INTEGER affinity. If neither
** 'x' nor the SELECT... statement are columns, then numeric affinity
** is used.
*/
SQLITE_PRIVATE void sqlite3CodeRhsOfIN(
Parse *pParse, /* Parsing context */
Expr *pExpr, /* The IN operator */
int iTab /* Use this cursor number */
){
int addrOnce = 0; /* Address of the OP_Once instruction at top */
int addr; /* Address of OP_OpenEphemeral instruction */
Expr *pLeft; /* the LHS of the IN operator */
KeyInfo *pKeyInfo = 0; /* Key information */
int nVal; /* Size of vector pLeft */
Vdbe *v; /* The prepared statement under construction */
v = pParse->pVdbe;
assert( v!=0 );
pLeft = pExpr->pLeft;
if( sqlite3ExprCheckIN(pParse, pExpr) ) return;
zAff = exprINAffinity(pParse, pExpr);
nVector = sqlite3ExprVectorSize(pExpr->pLeft);
aiMap = (int*)sqlite3DbMallocZero(
pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1
);
if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error;
/* Attempt to compute the RHS. After this step, if anything other than
** IN_INDEX_NOOP is returned, the table opened with cursor iTab
** contains the values that make up the RHS. If IN_INDEX_NOOP is returned,
** the RHS has not yet been coded. */
v = pParse->pVdbe;
assert( v!=0 ); /* OOM detected prior to this routine */
VdbeNoopComment((v, "begin IN expr"));
eType = sqlite3FindInIndex(pParse, pExpr,
IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK,
destIfFalse==destIfNull ? 0 : &rRhsHasNull,
aiMap, &iTab);
if( pParse->nErr>nErr ) pParse->db->errByteOffset = -1;
}
#endif /* SQLITE_OMIT_GENERATED_COLUMNS */
/*
** Generate code to extract the value of the iCol-th column of a table.
*/
SQLITE_PRIVATE void sqlite3ExprCodeGetColumnOfTable(
Vdbe *v, /* Parsing context */
Table *pTab, /* The table containing the value */
int iTabCur, /* The table cursor. Or the PK cursor for WITHOUT ROWID */
int iCol, /* Index of the column to extract */
int regOut /* Extract the value into this register */
){
Column *pCol;
assert( v!=0 );
assert( pTab!=0 );
assert( iCol!=XN_EXPR );
if( iCol<0 || iCol==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut);
VdbeComment((v, "%s.rowid", pTab->zName));
}
sqlite3VdbeAddOp3(v, op, iTabCur, x, regOut);
sqlite3ColumnDefault(v, pTab, iCol, regOut);
}
}
/*
** Generate code that will extract the iColumn-th column from
** table pTab and store the column value in register iReg.
**
** 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.
*/
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 */
u8 p5 /* P5 value for OP_Column + FLAGS */
){
assert( pParse->pVdbe!=0 );
assert( (p5 & (OPFLAG_NOCHNG|OPFLAG_TYPEOFARG|OPFLAG_LENGTHARG))==p5 );
assert( IsVirtual(pTab) || (p5 & OPFLAG_NOCHNG)==0 );
sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pTab, iTable, iColumn, iReg);
if( p5 ){
VdbeOp *pOp = sqlite3VdbeGetLastOp(pParse->pVdbe);
if( pOp->opcode==OP_Column ) pOp->p5 = p5;
w.u.iCur = iTab;
sqlite3WalkExpr(&w, p);
return w.eCode;
}
/*
** An instance of the following structure is used by the tree walker
** to determine if an expression can be evaluated by reference to the
** index only, without having to do a search for the corresponding
** table entry. The IdxCover.pIdx field is the index. IdxCover.iCur
** is the cursor for the table.
*/
struct IdxCover {
Index *pIdx; /* The index to be tested for coverage */
int iCur; /* Cursor number for the table corresponding to the index */
};
/*
** Check to see if there are references to columns in table
** pWalker->u.pIdxCover->iCur can be satisfied using the index
** pWalker->u.pIdxCover->pIdx.
&& pExpr->iTable==pWalker->u.pIdxCover->iCur
&& sqlite3TableColumnToIndex(pWalker->u.pIdxCover->pIdx, pExpr->iColumn)<0
){
pWalker->eCode = 1;
return WRC_Abort;
}
return WRC_Continue;
}
/*
** Determine if an index pIdx on table with cursor iCur contains will
** the expression pExpr. Return true if the index does cover the
** expression and false if the pExpr expression references table columns
** that are not found in the index pIdx.
**
** An index covering an expression means that the expression can be
** evaluated using only the index and without having to lookup the
** corresponding table entry.
*/
SQLITE_PRIVATE int sqlite3ExprCoveredByIndex(
Expr *pExpr, /* The index to be tested */
int iCur, /* The cursor number for the corresponding table */
Index *pIdx /* The index that might be used for coverage */
){
Walker w;
struct IdxCover xcov;
memset(&w, 0, sizeof(w));
xcov.iCur = iCur;
xcov.pIdx = pIdx;
w.xExprCallback = exprIdxCover;
w.u.pIdxCover = &xcov;
sqlite3WalkExpr(&w, pExpr);
** If the sqlite_statN tables do not previously exist, it is created.
**
** Argument zWhere may be a pointer to a buffer containing a table name,
** or it may be a NULL pointer. If it is not NULL, then all entries in
** the sqlite_statN tables associated with the named table are deleted.
** If zWhere==0, then code is generated to delete all stat table entries.
*/
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 for this table or index */
const char *zWhereType /* Either "tbl" or "idx" */
){
static const struct {
const char *zName;
const char *zCols;
} aTable[] = {
{ "sqlite_stat1", "tbl,idx,stat" },
#if defined(SQLITE_ENABLE_STAT4)
{ "sqlite_stat4", "tbl,idx,neq,nlt,ndlt,sample" },
/*
** 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 */
Index *pOnlyIdx, /* If not NULL, only analyze this one index */
int iStatCur, /* Index of VdbeCursor that writes the sqlite_stat1 table */
int iMem, /* Available memory locations begin here */
int iTab /* Next available cursor */
){
sqlite3 *db = pParse->db; /* Database handle */
Index *pIdx; /* An index to being analyzed */
int iIdxCur; /* Cursor open on index being analyzed */
int iTabCur; /* Table cursor */
Vdbe *v; /* The virtual machine being built up */
int i; /* Loop counter */
int jZeroRows = -1; /* Jump from here if number of rows is zero */
int iDb; /* Index of database containing pTab */
u8 needTableCnt = 1; /* True to count the table */
int regNewRowid = iMem++; /* Rowid for the inserted record */
int regStat = iMem++; /* Register to hold StatAccum object */
int regChng = iMem++; /* Index of changed index field */
int regRowid = iMem++; /* Rowid argument passed to stat_push() */
int regTemp = iMem++; /* Temporary use register */
if( pStat1==0 ) return;
pStat1->zName = (char*)&pStat1[1];
memcpy(pStat1->zName, "sqlite_stat1", 13);
pStat1->nCol = 3;
pStat1->iPKey = -1;
sqlite3VdbeAddOp4(pParse->pVdbe, OP_Noop, 0, 0, 0,(char*)pStat1,P4_DYNAMIC);
}
#endif
/* Establish a read-lock on the table at the shared-cache level.
** Open a read-only cursor on the table. Also allocate a cursor number
** to use for scanning indexes (iIdxCur). No index cursor is opened at
** this time though. */
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
iTabCur = iTab++;
iIdxCur = iTab++;
pParse->nTab = MAX(pParse->nTab, iTab);
sqlite3OpenTable(pParse, iTabCur, iDb, pTab, OP_OpenRead);
sqlite3VdbeLoadString(v, regTabname, pTab->zName);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int nCol; /* Number of columns in pIdx. "N" */
**
** end_of_scan:
*/
/* Make sure there are enough memory cells allocated to accommodate
** the regPrev array and a trailing rowid (the rowid slot is required
** when building a record to insert into the sample column of
** the sqlite_stat4 table. */
sqlite3TouchRegister(pParse, regPrev+nColTest);
/* Open a read-only cursor on the index being analyzed. */
assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb);
sqlite3VdbeSetP4KeyInfo(pParse, pIdx);
VdbeComment((v, "%s", pIdx->zName));
/* Implementation of the following:
**
** regChng = 0
** Rewind csr
** if eof(csr){
/* Finally, jump back to the beginning of the executable code. */
sqlite3VdbeGoto(v, 1);
}
/* Get the VDBE program ready for execution
*/
assert( v!=0 || pParse->nErr );
assert( db->mallocFailed==0 || pParse->nErr );
if( pParse->nErr==0 ){
/* A minimum of one cursor is required if autoincrement is used
* See ticket [a696379c1f08866] */
assert( pParse->pAinc==0 || pParse->nTab>0 );
sqlite3VdbeMakeReady(v, pParse);
pParse->rc = SQLITE_DONE;
}else{
pParse->rc = SQLITE_ERROR;
}
}
/*
zName = sqlite3DbStrNDup(db, (const char*)pName->z, pName->n);
sqlite3Dequote(zName);
}else{
zName = 0;
}
return zName;
}
/*
** Open the sqlite_schema table stored in database number iDb for
** writing. The table is opened using cursor 0.
*/
SQLITE_PRIVATE void sqlite3OpenSchemaTable(Parse *p, int iDb){
Vdbe *v = sqlite3GetVdbe(p);
sqlite3TableLock(p, iDb, SCHEMA_ROOT, 1, LEGACY_SCHEMA_TABLE);
sqlite3VdbeAddOp4Int(v, OP_OpenWrite, 0, SCHEMA_ROOT, iDb, 5);
if( p->nTab==0 ){
p->nTab = 1;
}
}
** be redundant.
*/
if( pSelect ){
SelectDest dest; /* Where the SELECT should store results */
int regYield; /* Register holding co-routine entry-point */
int addrTop; /* Top of the co-routine */
int regRec; /* A record to be insert into the new table */
int regRowid; /* Rowid of the next row to insert */
int addrInsLoop; /* Top of the loop for inserting rows */
Table *pSelTab; /* A table that describes the SELECT results */
int iCsr; /* Write cursor on the new table */
if( IN_SPECIAL_PARSE ){
pParse->rc = SQLITE_ERROR;
pParse->nErr++;
return;
}
iCsr = pParse->nTab++;
regYield = ++pParse->nMem;
regRec = ++pParse->nMem;
regRowid = ++pParse->nMem;
** SELECT * FROM temp.ex1;
*/
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( IsView(pTable) );
pSel = sqlite3SelectDup(db, pTable->u.view.pSelect, 0);
if( pSel ){
u8 eParseMode = pParse->eParseMode;
int nTab = pParse->nTab;
int nSelect = pParse->nSelect;
** 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++; /* Btree cursor used for pIndex */
int iSorter; /* Cursor opened by OpenSorter (if in use) */
int addr1; /* Address of top of loop */
int addr2; /* Address to jump to for next iteration */
Pgno tnum; /* Root page of index */
int iPartIdxLabel; /* Jump to this label to skip a row */
Vdbe *v; /* Generate code into this virtual machine */
KeyInfo *pKey; /* KeyInfo for index */
int regRecord; /* Register holding assembled index record */
sqlite3 *db = pParse->db; /* The database connection */
int iDb = sqlite3SchemaToIndex(db, pIndex->pSchema);
v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
if( memRootPage>=0 ){
tnum = (Pgno)memRootPage;
}else{
tnum = pIndex->tnum;
}
pKey = sqlite3KeyInfoOfIndex(pParse, pIndex);
assert( pKey!=0 || pParse->nErr );
/* Open the sorter cursor if we are to use one. */
iSorter = pParse->nTab++;
sqlite3VdbeAddOp4(v, OP_SorterOpen, iSorter, 0, pIndex->nKeyCol, (char*)
sqlite3KeyInfoRef(pKey), P4_KEYINFO);
/* Open the table. Loop through all rows of the table, inserting index
** records into the sorter. */
sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead);
addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, 0); VdbeCoverage(v);
regRecord = sqlite3GetTempReg(pParse);
sqlite3MultiWrite(pParse);
Expr *pWhere, /* The WHERE clause. May be null */
ExprList *pOrderBy, /* ORDER BY clause. May be null */
Expr *pLimit /* LIMIT clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iTabCur; /* Cursor number for the table */
int iDataCur = 0; /* VDBE cursor for the canonical data source */
int iIdxCur = 0; /* Cursor number of the first index */
int nIdx; /* Number of indices */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = 0; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
int eOnePass; /* ONEPASS_OFF or _SINGLE or _MULTI */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
u8 *aToOpen = 0; /* Open cursor iTabCur+j if aToOpen[j] is true */
Index *pPk; /* The PRIMARY KEY index on the table */
int iPk = 0; /* First of nPk registers holding PRIMARY KEY value */
i16 nPk = 1; /* Number of columns in the PRIMARY KEY */
int iKey; /* Memory cell holding key of row to be deleted */
i16 nKey; /* Number of memory cells in the row key */
int iEphCur = 0; /* Ephemeral table holding all primary key values */
int iRowSet = 0; /* Register for rowset of rows to delete */
int addrBypass = 0; /* Address of jump over the delete logic */
int addrLoop = 0; /* Top of the delete loop */
int addrEphOpen = 0; /* Instruction to open the Ephemeral table */
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0,
db->aDb[iDb].zDbSName);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor numbers to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iTabCur = pTabList->a[0].iCursor = pParse->nTab++;
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iEphCur, iKey, iPk, nPk);
}else{
/* Add the rowid of the row to be deleted to the RowSet */
nKey = 1; /* OP_DeferredSeek always uses a single rowid */
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
}
sqlite3WhereEnd(pWInfo);
}
/* Unless this is a view, open cursors for the table we are
** deleting from and all its indices. If this is a view, then the
** only effect this statement has is to fire the INSTEAD OF
** triggers.
*/
if( !isView ){
int iAddrOnce = 0;
if( eOnePass==ONEPASS_MULTI ){
iAddrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v);
}
testcase( IsVirtual(pTab) );
#undef pTrigger
#endif
/*
** This routine generates VDBE code that causes a single row of a
** single table to be deleted. Both the original table entry and
** all indices are removed.
**
** Preconditions:
**
** 1. iDataCur is an open cursor on the btree that is the canonical data
** store for the table. (This will be either the table itself,
** in the case of a rowid table, or the PRIMARY KEY index in the case
** of a WITHOUT ROWID table.)
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number iIdxCur+i for the i-th index.
**
** 3. The primary key for the row to be deleted must be stored in a
** sequence of nPk memory cells starting at iPk. If nPk==0 that means
** that a search record formed from OP_MakeRecord is contained in the
** single memory location iPk.
**
** eMode:
** Parameter eMode may be passed either ONEPASS_OFF (0), ONEPASS_SINGLE, or
** ONEPASS_MULTI. If eMode is not ONEPASS_OFF, then the cursor
** iDataCur already points to the row to delete. If eMode is ONEPASS_OFF
** then this function must seek iDataCur to the entry identified by iPk
** and nPk before reading from it.
**
** If eMode is ONEPASS_MULTI, then this call is being made as part
** of a ONEPASS delete that affects multiple rows. In this case, if
** iIdxNoSeek is a valid cursor number (>=0) and is not the same as
** iDataCur, then its position should be preserved following the delete
** operation. Or, if iIdxNoSeek is not a valid cursor number, the
** position of iDataCur should be preserved instead.
**
** iIdxNoSeek:
** If iIdxNoSeek is a valid cursor number (>=0) not equal to iDataCur,
** then it identifies an index cursor (from within array of cursors
** starting at iIdxCur) that already points to the index entry to be deleted.
** Except, this optimization is disabled if there are BEFORE triggers since
** the trigger body might have moved the cursor.
*/
SQLITE_PRIVATE void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
Trigger *pTrigger, /* List of triggers to (potentially) fire */
int iDataCur, /* Cursor from which column data is extracted */
int iIdxCur, /* First index cursor */
int iPk, /* First memory cell containing the PRIMARY KEY */
i16 nPk, /* Number of PRIMARY KEY memory cells */
u8 count, /* If non-zero, increment the row change counter */
u8 onconf, /* Default ON CONFLICT policy for triggers */
u8 eMode, /* ONEPASS_OFF, _SINGLE, or _MULTI. See above */
int iIdxNoSeek /* Cursor number of cursor that does not need seeking */
){
Vdbe *v = pParse->pVdbe; /* Vdbe */
int iOld = 0; /* First register in OLD.* array */
int iLabel; /* Label resolved to end of generated code */
u8 opSeek; /* Seek opcode */
/* Vdbe is guaranteed to have been allocated by this stage. */
assert( v );
VdbeModuleComment((v, "BEGIN: GenRowDel(%d,%d,%d,%d)",
iDataCur, iIdxCur, iPk, (int)nPk));
/* Seek cursor iCur to the row to delete. If this row no longer exists
** (this can happen if a trigger program has already deleted it), do
** not attempt to delete it or fire any DELETE triggers. */
iLabel = sqlite3VdbeMakeLabel(pParse);
opSeek = HasRowid(pTab) ? OP_NotExists : OP_NotFound;
if( eMode==ONEPASS_OFF ){
sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
VdbeCoverageIf(v, opSeek==OP_NotExists);
VdbeCoverageIf(v, opSeek==OP_NotFound);
}
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, iCol, iOld+kk+1);
}
}
/* Invoke BEFORE DELETE trigger programs. */
addrStart = sqlite3VdbeCurrentAddr(v);
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
);
/* If any BEFORE triggers were coded, then seek the cursor to the
** row to be deleted again. It may be that the BEFORE triggers moved
** the cursor or already deleted the row that the cursor was
** pointing to.
**
** Also disable the iIdxNoSeek optimization since the BEFORE trigger
** may have moved that cursor.
*/
if( addrStart<sqlite3VdbeCurrentAddr(v) ){
sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
VdbeCoverageIf(v, opSeek==OP_NotExists);
VdbeCoverageIf(v, opSeek==OP_NotFound);
testcase( iIdxNoSeek>=0 );
iIdxNoSeek = -1;
}
/* Do FK processing. This call checks that any FK constraints that
sqlite3VdbeResolveLabel(v, iLabel);
VdbeModuleComment((v, "END: GenRowDel()"));
}
/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table, pTab
**
** Preconditions:
**
** 1. A read/write cursor "iDataCur" must be open on the canonical storage
** btree for the table pTab. (This will be either the table itself
** for rowid tables or to the primary key index for WITHOUT ROWID
** tables.)
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number iIdxCur+i for the i-th index. (The pTab->pIndex
** index is the 0-th index.)
**
** 3. The "iDataCur" cursor must be already be positioned on 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 iDataCur, /* Cursor of table holding data. */
int iIdxCur, /* First index cursor */
int *aRegIdx, /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
int iIdxNoSeek /* Do not delete from this cursor */
){
int i; /* Index loop counter */
int r1 = -1; /* Register holding an index key */
int iPartIdxLabel; /* Jump destination for skipping partial index entries */
Index *pIdx; /* Current index */
Index *pPrior = 0; /* Prior index */
Vdbe *v; /* The prepared statement under construction */
Index *pPk; /* PRIMARY KEY index, or NULL for rowid tables */
v = pParse->pVdbe;
pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
sqlite3VdbeChangeP5(v, 1); /* Cause IdxDelete to error if no entry found */
sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel);
pPrior = pIdx;
}
}
/*
** Generate code that will assemble an index key and stores 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. If pTab is a WITHOUT ROWID table, then
** iCur must be the cursor of the PRIMARY KEY index.
**
** 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.
**
** If *piPartIdxLabel is not NULL, fill it in with a label and jump
** to that label if pIdx is a partial index that should be skipped.
** The label should be resolved using sqlite3ResolvePartIdxLabel().
** A partial index should be skipped if its WHERE clause evaluates
}else{
pExpr->iTable = regBase;
pExpr->affExpr = SQLITE_AFF_INTEGER;
}
}
return pExpr;
}
/*
** Return an Expr object that refers to column iCol of table pTab which
** has cursor iCur.
*/
static Expr *exprTableColumn(
sqlite3 *db, /* The database connection */
Table *pTab, /* The table whose column is desired */
int iCursor, /* The open cursor on the table */
i16 iCol /* The column that is wanted */
){
Expr *pExpr = sqlite3Expr(db, TK_COLUMN, 0);
if( pExpr ){
assert( ExprUseYTab(pExpr) );
pExpr->y.pTab = pTab;
pExpr->iTable = iCursor;
pExpr->iColumn = iCol;
}
return pExpr;
if( db->xAuth ){
int rcauth;
char *zCol = pTo->aCol[pIdx ? pIdx->aiColumn[i] : pTo->iPKey].zCnName;
rcauth = sqlite3AuthReadCol(pParse, pTo->zName, zCol, iDb);
bIgnore = (rcauth==SQLITE_IGNORE);
}
#endif
}
/* Take a shared-cache advisory read-lock on the parent table. Allocate
** a cursor to use to search the unique index on the parent key columns
** in the parent table. */
sqlite3TableLock(pParse, iDb, pTo->tnum, 0, pTo->zName);
pParse->nTab++;
if( regOld!=0 ){
/* A row is being removed from the child table. Search for the parent.
** If the parent does not exist, removing the child row resolves an
** outstanding foreign key constraint violation. */
fkLookupParent(pParse, iDb, pTo, pIdx, pFKey, aiCol, regOld, -1, bIgnore);
}
*************************************************************************
** This file contains C code routines that are called by the parser
** to handle INSERT statements in SQLite.
*/
/* #include "sqliteInt.h" */
/*
** Generate code that will
**
** (1) acquire a lock for table pTab then
** (2) open pTab as cursor iCur.
**
** If pTab is a WITHOUT ROWID table, then it is the PRIMARY KEY index
** for that table that is actually opened.
*/
SQLITE_PRIVATE void sqlite3OpenTable(
Parse *pParse, /* 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;
assert( !IsVirtual(pTab) );
assert( pParse->pVdbe!=0 );
v = pParse->pVdbe;
assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
if( !pParse->db->noSharedCache ){
** The co-routine method is used in most cases. Exceptions are:
**
** a) If the current statement has a WITH clause. This is to avoid
** statements like:
**
** WITH cte AS ( VALUES('x'), ('y') ... )
** SELECT * FROM cte AS a, cte AS b;
**
** This will not work, as the co-routine uses a hard-coded register
** for its OP_Yield instructions, and so it is not possible for two
** cursors to iterate through it concurrently.
**
** b) The schema is currently being parsed (i.e. the VALUES clause is part
** of a schema item like a VIEW or TRIGGER). In this case there is no VM
** being generated when parsing is taking place, and so generating
** a co-routine is not possible.
**
** c) There are non-constant expressions in the VALUES clause (e.g.
** the VALUES clause is part of a correlated sub-query).
**
** d) One or more of the values in the first row of the VALUES clause
** first two forms shown above. A VALUES clause is really just short-hand
** for a SELECT statement that omits the FROM clause and everything else
** that follows. If the pSelect parameter is NULL, that means that the
** DEFAULT VALUES form of the INSERT statement is intended.
**
** The code generated follows one of four templates. For a simple
** insert with data coming from a single-row 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:
** 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 */
int onError, /* How to handle constraint errors */
Upsert *pUpsert /* ON CONFLICT clauses for upsert, or NULL */
){
sqlite3 *db; /* The main database structure */
Table *pTab; /* The table to insert into. aka TABLE */
int i, j; /* 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 */
u8 useTempTable = 0; /* Store SELECT results in intermediate table */
u8 appendFlag = 0; /* True if the insert is likely to be an append */
u8 withoutRowid; /* 0 for normal table. 1 for WITHOUT ROWID table */
u8 bIdListInOrder; /* True if IDLIST is in table order */
ExprList *pList = 0; /* List of VALUES() to be inserted */
int iRegStore; /* Register in which to store next column */
);
if( db->flags & SQLITE_ForeignKeys ){
sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0);
}
/* Set the OPFLAG_USESEEKRESULT flag if either (a) there are no REPLACE
** constraints or (b) there are no triggers and this table is not a
** parent table in a foreign key constraint. It is safe to set the
** flag in the second case as if any REPLACE constraint is hit, an
** OP_Delete or OP_IdxDelete instruction will be executed on each
** cursor that is disturbed. And these instructions both clear the
** VdbeCursor.seekResult variable, disabling the OPFLAG_USESEEKRESULT
** functionality. */
bUseSeek = (isReplace==0 || !sqlite3VdbeHasSubProgram(v));
sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
regIns, aRegIdx, 0, appendFlag, bUseSeek
);
}
#ifdef SQLITE_ALLOW_ROWID_IN_VIEW
}else if( pParse->bReturning ){
/* If there is a RETURNING clause, populate the rowid register with
** at pTab->pIndex.
**
** (2019-05-07) The generated code also creates a new record for the
** main table, if pTab is a rowid table, and stores that record in the
** register identified by aRegIdx[nIdx] - in other words in the first
** entry of aRegIdx[] past the last index. It is important that the
** record be generated during constraint checks to avoid affinity changes
** to the register content that occur after constraint checks but before
** the new record is inserted.
**
** The caller must have already opened writeable cursors on the main
** table and all applicable indices (that is to say, all indices for which
** aRegIdx[] is not zero). iDataCur is the cursor for the main table when
** inserting or updating a rowid table, or the cursor for the PRIMARY KEY
** index when operating on a WITHOUT ROWID table. iIdxCur is the cursor
** for the first index in the pTab->pIndex list. Cursors for other indices
** are at iIdxCur+N for the N-th element of the pTab->pIndex list.
**
** 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
** --------------- ---------- ----------------------------------------
**
** 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.
*/
SQLITE_PRIVATE void sqlite3GenerateConstraintChecks(
Parse *pParse, /* The parser context */
Table *pTab, /* The table being inserted or updated */
int *aRegIdx, /* Use register aRegIdx[i] for index i. 0 for unused */
int iDataCur, /* Canonical data cursor (main table or PK index) */
int iIdxCur, /* First index cursor */
int regNewData, /* First register in a range holding values to insert */
int regOldData, /* Previous content. 0 for INSERTs */
u8 pkChng, /* Non-zero if the rowid or PRIMARY KEY changed */
u8 overrideError, /* Override onError to this if not OE_Default */
int ignoreDest, /* Jump to this label on an OE_Ignore resolution */
int *pbMayReplace, /* OUT: Set to true if constraint may cause a replace */
int *aiChng, /* column i is unchanged if aiChng[i]<0 */
Upsert *pUpsert /* ON CONFLICT clauses, if any. NULL otherwise */
){
Vdbe *v; /* VDBE under construction */
for(i=pTab->nCol-1; i>0; i--){
if( pTab->aCol[i].iDflt!=0 ) break;
if( pTab->aCol[i].colFlags & COLFLAG_PRIMKEY ) break;
}
sqlite3VdbeChangeP5(v, i+1);
}
#endif
/*
** Table pTab is a WITHOUT ROWID table that is being written to. The cursor
** number is iCur, and register regData contains the new record for the
** PK index. This function adds code to invoke the pre-update hook,
** if one is registered.
*/
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
static void codeWithoutRowidPreupdate(
Parse *pParse, /* Parse context */
Table *pTab, /* Table being updated */
int iCur, /* Cursor number for table */
int regData /* Data containing new record */
** A consecutive range of registers starting at regNewData 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 iDataCur, /* Cursor of the canonical data source */
int iIdxCur, /* First index cursor */
int regNewData, /* Range of content */
int *aRegIdx, /* Register used by each index. 0 for unused indices */
int update_flags, /* True for UPDATE, False for INSERT */
int appendBias, /* True if this is likely to be an append */
int useSeekResult /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */
){
Vdbe *v; /* Prepared statements under construction */
Index *pIdx; /* An index being inserted or updated */
u8 pik_flags; /* flag values passed to the btree insert */
int i; /* Loop counter */
pik_flags |= OPFLAG_USESEEKRESULT;
}
sqlite3VdbeAddOp3(v, OP_Insert, iDataCur, aRegIdx[i], regNewData);
if( !pParse->nested ){
sqlite3VdbeAppendP4(v, pTab, P4_TABLE);
}
sqlite3VdbeChangeP5(v, pik_flags);
}
/*
** Allocate cursors for the pTab table and all its indices and generate
** code to open and initialized those cursors.
**
** The cursor for the object that contains the complete data (normally
** the table itself, but the PRIMARY KEY index in the case of a WITHOUT
** ROWID table) is returned in *piDataCur. The first index cursor is
** returned in *piIdxCur. The number of indices is returned.
**
** Use iBase as the first cursor (either the *piDataCur for rowid tables
** or the first index for WITHOUT ROWID tables) if it is non-negative.
** If iBase is negative, then allocate the next available cursor.
**
** For a rowid table, *piDataCur will be exactly one less than *piIdxCur.
** For a WITHOUT ROWID table, *piDataCur will be somewhere in the range
** of *piIdxCurs, depending on where the PRIMARY KEY index appears on the
** pTab->pIndex list.
**
** If pTab is a virtual table, then this routine is a no-op and the
** *piDataCur and *piIdxCur values are left uninitialized.
*/
SQLITE_PRIVATE int sqlite3OpenTableAndIndices(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table to be opened */
int op, /* OP_OpenRead or OP_OpenWrite */
u8 p5, /* P5 value for OP_Open* opcodes (except on WITHOUT ROWID) */
int iBase, /* Use this for the table cursor, if there is one */
u8 *aToOpen, /* If not NULL: boolean for each table and index */
int *piDataCur, /* Write the database source cursor number here */
int *piIdxCur /* Write the first index cursor number here */
){
int i;
int iDb;
int iDataCur;
Index *pIdx;
Vdbe *v;
assert( op==OP_OpenRead || op==OP_OpenWrite );
assert( op==OP_OpenWrite || p5==0 );
assert( piDataCur!=0 );
assert( piIdxCur!=0 );
if( IsVirtual(pTab) ){
/* This routine is a no-op for virtual tables. Leave the output
** variables *piDataCur and *piIdxCur set to illegal cursor numbers
** for improved error detection. */
*piDataCur = *piIdxCur = -999;
return 0;
}
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
v = pParse->pVdbe;
assert( v!=0 );
if( iBase<0 ) iBase = pParse->nTab;
iDataCur = iBase++;
*piDataCur = iDataCur;
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
sqlite3VdbeAddOp2(v, OP_Integer, 0, 8+j); /* index entries counter */
}
assert( pParse->nMem>=8+j );
assert( sqlite3NoTempsInRange(pParse,1,7+j) );
sqlite3VdbeAddOp2(v, OP_Rewind, iDataCur, 0); VdbeCoverage(v);
loopTop = sqlite3VdbeAddOp2(v, OP_AddImm, 7, 1);
/* Fetch the right-most column from the table. This will cause
** the entire record header to be parsed and sanity checked. It
** will also prepopulate the cursor column cache that is used
** by the OP_IsType code, so it is a required step.
*/
assert( !IsVirtual(pTab) );
if( HasRowid(pTab) ){
mxCol = -1;
for(j=0; j<pTab->nCol; j++){
if( (pTab->aCol[j].colFlags & COLFLAG_VIRTUAL)==0 ) mxCol++;
}
if( mxCol==pTab->iPKey ) mxCol--;
}else{
typedef struct PragmaVtab PragmaVtab;
typedef struct PragmaVtabCursor PragmaVtabCursor;
struct PragmaVtab {
sqlite3_vtab base; /* Base class. Must be first */
sqlite3 *db; /* The database connection to which it belongs */
const PragmaName *pName; /* Name of the pragma */
u8 nHidden; /* Number of hidden columns */
u8 iHidden; /* Index of the first hidden column */
};
struct PragmaVtabCursor {
sqlite3_vtab_cursor base; /* Base class. Must be first */
sqlite3_stmt *pPragma; /* The pragma statement to run */
sqlite_int64 iRowid; /* Current rowid */
char *azArg[2]; /* Value of the argument and schema */
};
/*
** Pragma virtual table module xConnect method.
*/
static int pragmaVtabConnect(
sqlite3 *db,
pIdxInfo->estimatedCost = (double)20;
pIdxInfo->estimatedRows = 20;
if( seen[1] ){
j = seen[1]-1;
pIdxInfo->aConstraintUsage[j].argvIndex = 2;
pIdxInfo->aConstraintUsage[j].omit = 1;
}
return SQLITE_OK;
}
/* Create a new cursor for the pragma virtual table */
static int pragmaVtabOpen(sqlite3_vtab *pVtab, sqlite3_vtab_cursor **ppCursor){
PragmaVtabCursor *pCsr;
pCsr = (PragmaVtabCursor*)sqlite3_malloc(sizeof(*pCsr));
if( pCsr==0 ) return SQLITE_NOMEM;
memset(pCsr, 0, sizeof(PragmaVtabCursor));
pCsr->base.pVtab = pVtab;
*ppCursor = &pCsr->base;
return SQLITE_OK;
}
/* Clear all content from pragma virtual table cursor. */
static void pragmaVtabCursorClear(PragmaVtabCursor *pCsr){
int i;
sqlite3_finalize(pCsr->pPragma);
pCsr->pPragma = 0;
pCsr->iRowid = 0;
for(i=0; i<ArraySize(pCsr->azArg); i++){
sqlite3_free(pCsr->azArg[i]);
pCsr->azArg[i] = 0;
}
}
/* Close a pragma virtual table cursor */
static int pragmaVtabClose(sqlite3_vtab_cursor *cur){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)cur;
pragmaVtabCursorClear(pCsr);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/* Advance the pragma virtual table cursor to the next row */
static int pragmaVtabNext(sqlite3_vtab_cursor *pVtabCursor){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
int rc = SQLITE_OK;
/* Increment the xRowid value */
pCsr->iRowid++;
assert( pCsr->pPragma );
if( SQLITE_ROW!=sqlite3_step(pCsr->pPragma) ){
rc = sqlite3_finalize(pCsr->pPragma);
pCsr->pPragma = 0;
pragmaVtabCursorClear(pCsr);
}
return rc;
}
/*
** Pragma virtual table module xFilter method.
*/
static int pragmaVtabFilter(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
PragmaVtab *pTab = (PragmaVtab*)(pVtabCursor->pVtab);
int rc;
int i, j;
StrAccum acc;
char *zSql;
if( rc!=SQLITE_OK ){
pTab->base.zErrMsg = sqlite3_mprintf("%s", sqlite3_errmsg(pTab->db));
return rc;
}
return pragmaVtabNext(pVtabCursor);
}
/*
** Pragma virtual table module xEof method.
*/
static int pragmaVtabEof(sqlite3_vtab_cursor *pVtabCursor){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
return (pCsr->pPragma==0);
}
/* The xColumn method simply returns the corresponding column from
** the PRAGMA.
*/
static int pragmaVtabColumn(
sqlite3_vtab_cursor *pVtabCursor,
sqlite3_context *ctx,
int i
){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
PragmaVtab *pTab = (PragmaVtab*)(pVtabCursor->pVtab);
if( i<pTab->iHidden ){
sqlite3_result_value(ctx, sqlite3_column_value(pCsr->pPragma, i));
}else{
sqlite3_result_text(ctx, pCsr->azArg[i-pTab->iHidden],-1,SQLITE_TRANSIENT);
}
return SQLITE_OK;
}
/*
** Pragma virtual table module xRowid method.
*/
static int pragmaVtabRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *p){
PragmaVtabCursor *pCsr = (PragmaVtabCursor*)pVtabCursor;
*p = pCsr->iRowid;
return SQLITE_OK;
}
/* The pragma virtual table object */
static const sqlite3_module pragmaVtabModule = {
0, /* iVersion */
0, /* xCreate - create a table */
pragmaVtabConnect, /* xConnect - connect to an existing table */
pragmaVtabBestIndex, /* xBestIndex - Determine search strategy */
pragmaVtabDisconnect, /* xDisconnect - Disconnect from a table */
0, /* xDestroy - Drop a table */
pragmaVtabOpen, /* xOpen - open a cursor */
pragmaVtabClose, /* xClose - close a cursor */
pragmaVtabFilter, /* xFilter - configure scan constraints */
pragmaVtabNext, /* xNext - advance a cursor */
pragmaVtabEof, /* xEof */
pragmaVtabColumn, /* xColumn - read data */
pragmaVtabRowid, /* xRowid - read data */
0, /* xUpdate - write data */
0, /* xBegin - begin transaction */
0, /* xSync - sync transaction */
0, /* xCommit - commit transaction */
0, /* xRollback - rollback transaction */
0, /* xFindFunction - function overloading */
0, /* xRename - rename the table */
initData.mInitFlags = mFlags;
initData.nInitRow = 0;
initData.mxPage = 0;
sqlite3InitCallback(&initData, 5, (char **)azArg, 0);
db->mDbFlags &= mask;
if( initData.rc ){
rc = initData.rc;
goto error_out;
}
/* Create a cursor to hold the database open
*/
pDb = &db->aDb[iDb];
if( pDb->pBt==0 ){
assert( iDb==1 );
DbSetProperty(db, 1, DB_SchemaLoaded);
rc = SQLITE_OK;
goto error_out;
}
/* If there is not already a read-only (or read-write) transaction opened
** Add code that will check to make sure the array of registers starting at
** iMem form a distinct entry. This is used by both "SELECT DISTINCT ..." and
** distinct aggregates ("SELECT count(DISTINCT <expr>) ..."). Three strategies
** are available. Which is used depends on the value of parameter eTnctType,
** as follows:
**
** WHERE_DISTINCT_UNORDERED/WHERE_DISTINCT_NOOP:
** Build an ephemeral table that contains all entries seen before and
** skip entries which have been seen before.
**
** Parameter iTab is the cursor number of an ephemeral table that must
** be opened before the VM code generated by this routine is executed.
** The ephemeral cursor table is queried for a record identical to the
** record formed by the current array of registers. If one is found,
** jump to VM address addrRepeat. Otherwise, insert a new record into
** the ephemeral cursor and proceed.
**
** The returned value in this case is a copy of parameter iTab.
**
** WHERE_DISTINCT_ORDERED:
** In this case rows are being delivered sorted order. The ephemeral
** table is not required. Instead, the current set of values
** is compared against previous row. If they match, the new row
** is not distinct and control jumps to VM address addrRepeat. Otherwise,
** the VM program proceeds with processing the new row.
**
** If the optimization is used for expression "bigblob", then instead of
** storing values read from that column in the sorter records, the PK of
** the row from table t1 is stored instead. Then, as records are extracted from
** the sorter to return to the user, the required value of bigblob is
** retrieved directly from table t1. If the values are very large, this
** can be more efficient than storing them directly in the sorter records.
**
** The ExprList_item.fg.bSorterRef flag is set for each expression in pEList
** for which the sorter-reference optimization should be enabled.
** Additionally, the pSort->aDefer[] array is populated with entries
** for all cursors required to evaluate all selected expressions. Finally.
** output variable (*ppExtra) is set to an expression list containing
** expressions for all extra PK values that should be stored in the
** sorter records.
*/
static void selectExprDefer(
Parse *pParse, /* Leave any error here */
SortCtx *pSort, /* Sorter context */
ExprList *pEList, /* Expressions destined for sorter */
ExprList **ppExtra /* Expressions to append to sorter record */
){
** that this is an "UPDATE ... FROM" on a virtual table or view. In this
** case set the p5 parameter of the OP_MakeRecord to OPFLAG_NOCHNG_MAGIC.
** This does not affect operation in any way - it just allows MakeRecord
** to process OPFLAG_NOCHANGE values without an assert() failing. */
if( eDest==SRT_Table && pDest->iSDParm2 ){
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC);
}
#endif
#ifndef SQLITE_OMIT_CTE
if( eDest==SRT_DistFifo ){
/* If the destination is DistFifo, then cursor (iParm+1) is open
** on an ephemeral index. If the current row is already present
** in the index, do not write it to the output. If not, add the
** current row to the index and proceed with writing it to the
** output table as well. */
int addr = sqlite3VdbeCurrentAddr(v) + 4;
sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, addr, r1, 0);
VdbeCoverage(v);
sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iParm+1, r1,regResult,nResultCol);
assert( pSort==0 );
}
}else if( eDest==SRT_Coroutine ){
sqlite3VdbeAddOp1(v, OP_Yield, pDest->iSDParm);
}else{
sqlite3VdbeAddOp2(v, OP_ResultRow, regResult, nResultCol);
}
break;
}
#ifndef SQLITE_OMIT_CTE
/* Write the results into a priority queue that is order according to
** pDest->pOrderBy (in pSO). pDest->iSDParm (in iParm) is the cursor for an
** index with pSO->nExpr+2 columns. Build a key using pSO for the first
** pSO->nExpr columns, then make sure all keys are unique by adding a
** final OP_Sequence column. The last column is the record as a blob.
*/
case SRT_DistQueue:
case SRT_Queue: {
int nKey;
int r1, r2, r3;
int addrTest = 0;
ExprList *pSO;
pSO = pDest->pOrderBy;
assert( pSO );
nKey = pSO->nExpr;
r1 = sqlite3GetTempReg(pParse);
r2 = sqlite3GetTempRange(pParse, nKey+2);
r3 = r2+nKey+1;
if( eDest==SRT_DistQueue ){
/* If the destination is DistQueue, then cursor (iParm+1) is open
** on a second ephemeral index that holds all values every previously
** added to the queue. */
addrTest = sqlite3VdbeAddOp4Int(v, OP_Found, iParm+1, 0,
regResult, nResultCol);
VdbeCoverage(v);
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regResult, nResultCol, r3);
if( eDest==SRT_DistQueue ){
sqlite3VdbeAddOp2(v, OP_IdxInsert, iParm+1, r3);
sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT);
int addr; /* Top of output loop. Jump for Next. */
int addrOnce = 0;
int iTab;
ExprList *pOrderBy = pSort->pOrderBy;
int eDest = pDest->eDest;
int iParm = pDest->iSDParm;
int regRow;
int regRowid;
int iCol;
int nKey; /* Number of key columns in sorter record */
int iSortTab; /* Sorter cursor to read from */
int i;
int bSeq; /* True if sorter record includes seq. no. */
int nRefKey = 0;
struct ExprList_item *aOutEx = p->pEList->a;
#ifdef SQLITE_ENABLE_STMT_SCANSTATUS
int addrExplain; /* Address of OP_Explain instruction */
#endif
nKey = pOrderBy->nExpr - pSort->nOBSat;
if( pSort->nOBSat==0 || nKey==1 ){
assert( addrBreak<0 );
if( pSort->labelBkOut ){
sqlite3VdbeAddOp2(v, OP_Gosub, pSort->regReturn, pSort->labelBkOut);
sqlite3VdbeGoto(v, addrBreak);
sqlite3VdbeResolveLabel(v, pSort->labelBkOut);
}
#ifdef SQLITE_ENABLE_SORTER_REFERENCES
/* Open any cursors needed for sorter-reference expressions */
for(i=0; i<pSort->nDefer; i++){
Table *pTab = pSort->aDefer[i].pTab;
int iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
sqlite3OpenTable(pParse, pSort->aDefer[i].iCsr, iDb, pTab, OP_OpenRead);
nRefKey = MAX(nRefKey, pSort->aDefer[i].nKey);
}
#endif
iTab = pSort->iECursor;
if( eDest==SRT_Output || eDest==SRT_Coroutine || eDest==SRT_Mem ){
addrBreak = sqlite3VdbeMakeLabel(pParse);
p->nSelectRow = 320; /* 4 billion rows */
computeLimitRegisters(pParse, p, addrBreak);
pLimit = p->pLimit;
regLimit = p->iLimit;
regOffset = p->iOffset;
p->pLimit = 0;
p->iLimit = p->iOffset = 0;
pOrderBy = p->pOrderBy;
/* Locate the cursor number of the Current table */
for(i=0; ALWAYS(i<pSrc->nSrc); i++){
if( pSrc->a[i].fg.isRecursive ){
iCurrent = pSrc->a[i].iCursor;
break;
}
}
/* Allocate cursors numbers for Queue and Distinct. The cursor number for
** the Distinct table must be exactly one greater than Queue in order
** for the SRT_DistFifo and SRT_DistQueue destinations to work. */
iQueue = pParse->nTab++;
if( p->op==TK_UNION ){
eDest = pOrderBy ? SRT_DistQueue : SRT_DistFifo;
iDistinct = pParse->nTab++;
}else{
eDest = pOrderBy ? SRT_Queue : SRT_Fifo;
}
sqlite3SelectDestInit(&destQueue, eDest, iQueue);
/* Allocate cursors for Current, Queue, and Distinct. */
regCurrent = ++pParse->nMem;
sqlite3VdbeAddOp3(v, OP_OpenPseudo, iCurrent, regCurrent, nCol);
if( pOrderBy ){
KeyInfo *pKeyInfo = multiSelectOrderByKeyInfo(pParse, p, 1);
sqlite3VdbeAddOp4(v, OP_OpenEphemeral, iQueue, pOrderBy->nExpr+2, 0,
(char*)pKeyInfo, P4_KEYINFO);
destQueue.pOrderBy = pOrderBy;
}else{
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iQueue, nCol);
}
/* Make arrangements to free the 2nd and subsequent arms of the compound
** after the parse has finished */
if( pSplit->pPrior ){
sqlite3ParserAddCleanup(pParse, sqlite3SelectDeleteGeneric, pSplit->pPrior);
}
pSplit->pPrior = pPrior;
pPrior->pNext = pSplit;
sqlite3ExprListDelete(db, pPrior->pOrderBy);
pPrior->pOrderBy = 0;
/*** TBD: Insert subroutine calls to close cursors on incomplete
**** subqueries ****/
ExplainQueryPlanPop(pParse);
return pParse->nErr!=0;
}
#endif
#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
/* An instance of the SubstContext object describes an substitution edit
** to be performed on a parse tree.
static void substSelect(SubstContext*, Select*, int);
/*
** 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 makes 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 Expr *substExpr(
SubstContext *pSubst, /* Description of the substitution */
Expr *pExpr /* Expr in which substitution occurs */
){
if( pExpr==0 ) return 0;
if( ExprHasProperty(pExpr, EP_OuterON|EP_InnerON)
w.xExprCallback = recomputeColumnsUsedExpr;
w.xSelectCallback = sqlite3SelectWalkNoop;
w.u.pSrcItem = pSrcItem;
pSrcItem->colUsed = 0;
sqlite3WalkSelect(&w, pSelect);
}
#endif /* !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW) */
#if !defined(SQLITE_OMIT_SUBQUERY) || !defined(SQLITE_OMIT_VIEW)
/*
** Assign new cursor numbers to each of the items in pSrc. For each
** new cursor number assigned, set an entry in the aCsrMap[] array
** to map the old cursor number to the new:
**
** aCsrMap[iOld+1] = iNew;
**
** The array is guaranteed by the caller to be large enough for all
** existing cursor numbers in pSrc. aCsrMap[0] is the array size.
**
** If pSrc contains any sub-selects, call this routine recursively
** on the FROM clause of each such sub-select, with iExcept set to -1.
*/
static void srclistRenumberCursors(
Parse *pParse, /* Parse context */
int *aCsrMap, /* Array to store cursor mappings in */
SrcList *pSrc, /* FROM clause to renumber */
int iExcept /* FROM clause item to skip */
){
int i;
SrcItem *pItem;
for(i=0, pItem=pSrc->a; i<pSrc->nSrc; i++, pItem++){
if( i!=iExcept ){
Select *p;
assert( pItem->iCursor < aCsrMap[0] );
if( !pItem->fg.isRecursive || aCsrMap[pItem->iCursor+1]==0 ){
}
pItem->iCursor = aCsrMap[pItem->iCursor+1];
for(p=pItem->pSelect; p; p=p->pPrior){
srclistRenumberCursors(pParse, aCsrMap, p->pSrc, -1);
}
}
}
}
/*
** *piCursor is a cursor number. Change it if it needs to be mapped.
*/
static void renumberCursorDoMapping(Walker *pWalker, int *piCursor){
int *aCsrMap = pWalker->u.aiCol;
int iCsr = *piCursor;
if( iCsr < aCsrMap[0] && aCsrMap[iCsr+1]>0 ){
*piCursor = aCsrMap[iCsr+1];
}
}
/*
** Expression walker callback used by renumberCursors() to update
** Expr objects to match newly assigned cursor numbers.
*/
static int renumberCursorsCb(Walker *pWalker, Expr *pExpr){
int op = pExpr->op;
if( op==TK_COLUMN || op==TK_IF_NULL_ROW ){
renumberCursorDoMapping(pWalker, &pExpr->iTable);
}
if( ExprHasProperty(pExpr, EP_OuterON) ){
renumberCursorDoMapping(pWalker, &pExpr->w.iJoin);
}
return WRC_Continue;
}
/*
** Assign a new cursor number to each cursor in the FROM clause (Select.pSrc)
** of the SELECT statement passed as the second argument, and to each
** cursor in the FROM clause of any FROM clause sub-selects, recursively.
** Except, do not assign a new cursor number to the iExcept'th element in
** the FROM clause of (*p). Update all expressions and other references
** to refer to the new cursor numbers.
**
** Argument aCsrMap is an array that may be used for temporary working
** space. Two guarantees are made by the caller:
**
** * the array is larger than the largest cursor number used within the
** select statement passed as an argument, and
**
** * the array entries for all cursor numbers that do *not* appear in
** FROM clauses of the select statement as described above are
** initialized to zero.
*/
static void renumberCursors(
Parse *pParse, /* Parse context */
Select *p, /* Select to renumber cursors within */
int iExcept, /* FROM clause item to skip */
int *aCsrMap /* Working space */
){
Walker w;
srclistRenumberCursors(pParse, aCsrMap, p->pSrc, iExcept);
memset(&w, 0, sizeof(w));
w.u.aiCol = aCsrMap;
w.xExprCallback = renumberCursorsCb;
w.xSelectCallback = sqlite3SelectWalkNoop;
sqlite3WalkSelect(&w, p);
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 */
){
const char *zSavedAuthContext = pParse->zAuthContext;
Select *pParent; /* Current UNION ALL term of the other query */
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 */
int iParent; /* VDBE cursor number of the pSub result set temp table */
int iNewParent = -1;/* Replacement table for iParent */
int isOuterJoin = 0; /* True if pSub is the right side of a LEFT JOIN */
int i; /* Loop counter */
Expr *pWhere; /* The WHERE clause */
SrcItem *pSubitem; /* The subquery */
sqlite3 *db = pParse->db;
Walker w; /* Walker to persist agginfo data */
int *aCsrMap = 0;
/* Check to see if flattening is permitted. Return 0 if not.
pSubitem->pTab = 0;
}
/* The following loop runs once for each term in a compound-subquery
** flattening (as described above). If we are doing a different kind
** of flattening - a flattening other than a compound-subquery flattening -
** then this loop only runs once.
**
** This loop moves 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.
*/
pSub = pSub1;
for(pParent=p; pParent; pParent=pParent->pPrior, pSub=pSub->pPrior){
int nSubSrc;
u8 jointype = 0;
u8 ltorj = pSrc->a[iFrom].fg.jointype & JT_LTORJ;
assert( pSub!=0 );
if( sqlite3IdListIndex(pBase->u3.pUsing, zName)>=0 ) return 1;
}
return 0;
}
/*
** This routine is a Walker callback for "expanding" a SELECT statement.
** "Expanding" means to do the following:
**
** (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 persistent representation
** of the view.
**
if( p->pWith==0 ){
p->pWith = (With*)sqlite3DbMallocZero(db, sizeof(With));
if( p->pWith==0 ){
return WRC_Abort;
}
}
p->pWith->bView = 1;
}
sqlite3WithPush(pParse, p->pWith, 0);
/* Make sure cursor numbers have been assigned to all entries in
** the FROM clause of the SELECT statement.
*/
sqlite3SrcListAssignCursors(pParse, pTabList);
/* 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;
pAggInfo->nSortingColumn = mx+1;
}
analyzeAggFuncArgs(pAggInfo, pNC);
#if TREETRACE_ENABLED
if( sqlite3TreeTrace & 0x20 ){
IndexedExpr *pIEpr;
TREETRACE(0x20, pParse, pSelect,
("AggInfo (possibly) adjusted for Indexed Exprs\n"));
sqlite3TreeViewSelect(0, pSelect, 0);
for(pIEpr=pParse->pIdxEpr; pIEpr; pIEpr=pIEpr->pIENext){
printf("data-cursor=%d index={%d,%d}\n",
pIEpr->iDataCur, pIEpr->iIdxCur, pIEpr->iIdxCol);
sqlite3TreeViewExpr(0, pIEpr->pExpr, 0);
}
printAggInfo(pAggInfo);
}
#else
UNUSED_PARAMETER(pSelect);
UNUSED_PARAMETER(pParse);
#endif
}
sqlite3ReleaseTempRange(pParse, regAgg, nArg);
}
sqlite3VdbeAddOp2(v, OP_AggFinal, AggInfoFuncReg(pAggInfo,i),
pList ? pList->nExpr : 0);
sqlite3VdbeAppendP4(v, pF->pFunc, P4_FUNCDEF);
}
}
/*
** Generate code that will update the accumulator memory cells for an
** aggregate based on the current cursor position.
**
** If regAcc is non-zero and there are no min() or max() aggregates
** in pAggInfo, then only populate the pAggInfo->nAccumulator accumulator
** registers if register regAcc contains 0. The caller will take care
** of setting and clearing regAcc.
**
** For an ORDER BY aggregate, the actual accumulator memory cell update
** is deferred until after all input rows have been received, so that they
** can be run in the requested order. In that case, instead of invoking
** OP_AggStep to update the accumulator, just add the arguments that would
){
pBest = pIdx;
}
}
}
if( pBest ){
iRoot = pBest->tnum;
pKeyInfo = sqlite3KeyInfoOfIndex(pParse, pBest);
}
/* Open a read-only cursor, execute the OP_Count, close the cursor. */
sqlite3VdbeAddOp4Int(v, OP_OpenRead, iCsr, (int)iRoot, iDb, 1);
if( pKeyInfo ){
sqlite3VdbeChangeP4(v, -1, (char *)pKeyInfo, P4_KEYINFO);
}
assignAggregateRegisters(pParse, pAggInfo);
sqlite3VdbeAddOp2(v, OP_Count, iCsr, AggInfoFuncReg(pAggInfo,0));
sqlite3VdbeAddOp1(v, OP_Close, iCsr);
explainSimpleCount(pParse, pTab, pBest);
}else{
int regAcc = 0; /* "populate accumulators" flag */
if( pRet ) pRet->iColumn = iCol+1;
return pRet;
}
/*
** Assuming both the pLimit and pOrderBy parameters are NULL, this function
** generates VM code to run the query:
**
** SELECT <other-columns>, pChanges FROM pTabList WHERE pWhere
**
** and write the results to the ephemeral table already opened as cursor
** iEph. None of pChanges, pTabList or pWhere are modified or consumed by
** this function, they must be deleted by the caller.
**
** Or, if pLimit and pOrderBy are not NULL, and pTab is not a view:
**
** SELECT <other-columns>, pChanges FROM pTabList
** WHERE pWhere
** GROUP BY <other-columns>
** ORDER BY pOrderBy LIMIT pLimit
**
){
int i, j, k; /* Loop counters */
Table *pTab; /* The table to be updated */
int addrTop = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo = 0; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
Index *pPk; /* The PRIMARY KEY index for WITHOUT ROWID tables */
int nIdx; /* Number of indices that need updating */
int nAllIdx; /* Total number of indexes */
int iBaseCur; /* Base cursor number */
int iDataCur; /* Cursor for the canonical data btree */
int iIdxCur; /* Cursor for the first index */
sqlite3 *db; /* The database structure */
int *aRegIdx = 0; /* Registers for to each index and the main table */
int *aXRef = 0; /* aXRef[i] is the index in pChanges->a[] of the
** an expression for the i-th column of the table.
** aXRef[i]==-1 if the i-th column is not changed. */
u8 *aToOpen; /* 1 for tables and indices to be opened */
u8 chngPk; /* PRIMARY KEY changed in a WITHOUT ROWID table */
u8 chngRowid; /* Rowid changed in a normal table */
int flags; /* Flags for sqlite3WhereBegin() */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True when updating a view (INSTEAD OF trigger) */
Trigger *pTrigger; /* List of triggers on pTab, if required */
int tmask; /* Mask of TRIGGER_BEFORE|TRIGGER_AFTER */
#endif
int newmask; /* Mask of NEW.* columns accessed by BEFORE triggers */
int iEph = 0; /* Ephemeral table holding all primary key values */
int nKey = 0; /* Number of elements in regKey for WITHOUT ROWID */
int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
int addrOpen = 0; /* Address of OP_OpenEphemeral */
int iPk = 0; /* First of nPk cells holding PRIMARY KEY value */
i16 nPk = 0; /* Number of components of the PRIMARY KEY */
int bReplace = 0; /* True if REPLACE conflict resolution might happen */
int bFinishSeek = 1; /* The OP_FinishSeek opcode is needed */
int nChangeFrom = 0; /* If there is a FROM, pChanges->nExpr, else 0 */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid = 0; /* The old rowid */
}
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, pTrigger) ){
goto update_cleanup;
}
/* 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.
*/
iBaseCur = iDataCur = pParse->nTab++;
iIdxCur = iDataCur+1;
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
testcase( pPk!=0 && pPk!=pTab->pIndex );
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
if( pPk==pIdx ){
iDataCur = pParse->nTab;
}
pParse->nTab++;
}
if( pUpsert ){
/* On an UPSERT, reuse the same cursors already opened by INSERT */
iDataCur = pUpsert->iDataCur;
iIdxCur = pUpsert->iIdxCur;
pParse->nTab = iBaseCur;
}
pTabList->a[0].iCursor = iDataCur;
/* Allocate space for aXRef[], aRegIdx[], and aToOpen[].
** Initialize aXRef[] and aToOpen[] to their default values.
*/
aXRef = sqlite3DbMallocRawNN(db, sizeof(int) * (pTab->nCol+nIdx+1) + nIdx+2 );
}
break;
}
}
}
if( reg==0 ) aToOpen[nAllIdx+1] = 0;
aRegIdx[nAllIdx] = reg;
}
aRegIdx[nAllIdx] = ++pParse->nMem; /* Register storing the table record */
if( bReplace ){
/* If REPLACE conflict resolution might be invoked, open cursors on all
** indexes in case they are needed to delete records. */
memset(aToOpen, 1, nIdx+1);
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, pTrigger || hasFK, iDb);
/* Allocate required registers. */
if( !IsVirtual(pTab) ){
/* For now, regRowSet and aRegIdx[nAllIdx] share the same register.
}
}
if( nChangeFrom ){
sqlite3MultiWrite(pParse);
eOnePass = ONEPASS_OFF;
nKey = nPk;
regKey = iPk;
}else{
if( pUpsert ){
/* If this is an UPSERT, then all cursors have already been opened by
** the outer INSERT and the data cursor should be pointing at the row
** that is to be updated. So bypass the code that searches for the
** row(s) to be updated.
*/
pWInfo = 0;
eOnePass = ONEPASS_SINGLE;
sqlite3ExprIfFalse(pParse, pWhere, labelBreak, SQLITE_JUMPIFNULL);
bFinishSeek = 0;
}else{
/* Begin the database scan.
**
** Do not consider a single-pass strategy for a multi-row update if
** there is anything that might disrupt the cursor being used to do
** the UPDATE:
** (1) This is a nested UPDATE
** (2) There are triggers
** (3) There are FOREIGN KEY constraints
** (4) There are REPLACE conflict handlers
** (5) There are subqueries in the WHERE clause
*/
flags = WHERE_ONEPASS_DESIRED;
if( !pParse->nested
&& !pTrigger
if( !isView ){
/* Do constraint checks. */
assert( regOldRowid>0 );
sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace,
aXRef, 0);
/* If REPLACE conflict handling may have been used, or if the PK of the
** row is changing, then the GenerateConstraintChecks() above may have
** moved cursor iDataCur. Reseek it. */
if( bReplace || chngKey ){
if( pPk ){
sqlite3VdbeAddOp4Int(v, OP_NotFound,iDataCur,labelContinue,regKey,nKey);
}else{
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue,regOldRowid);
}
VdbeCoverage(v);
}
/* Do FK constraint checks. */
){
pUpsert = pUpsert->pNextUpsert;
}
return pUpsert;
}
/*
** Generate bytecode that does an UPDATE as part of an upsert.
**
** If pIdx is NULL, then the UNIQUE constraint that failed was the IPK.
** In this case parameter iCur is a cursor open on the table b-tree that
** currently points to the conflicting table row. Otherwise, if pIdx
** is not NULL, then pIdx is the constraint that failed and iCur is a
** cursor points to the conflicting row.
*/
SQLITE_PRIVATE void sqlite3UpsertDoUpdate(
Parse *pParse, /* The parsing and code-generating context */
Upsert *pUpsert, /* The ON CONFLICT clause for the upsert */
Table *pTab, /* The table being updated */
Index *pIdx, /* The UNIQUE constraint that failed */
int iCur /* Cursor for pIdx (or pTab if pIdx==NULL) */
){
Vdbe *v = pParse->pVdbe;
sqlite3 *db = pParse->db;
** its elements.
**
** The WhereInfo object contains a single instance of this object for
** each term in the FROM clause (which is to say, for each of the
** nested loops as implemented). The order of WhereLevel objects determines
** the loop nested order, with WhereInfo.a[0] being the outer loop and
** WhereInfo.a[WhereInfo.nLevel-1] being the inner loop.
*/
struct WhereLevel {
int iLeftJoin; /* Memory cell used to implement LEFT OUTER JOIN */
int iTabCur; /* The VDBE cursor used to access the table */
int iIdxCur; /* The VDBE cursor used to access pIdx */
int addrBrk; /* Jump here to break out of the loop */
int addrNxt; /* Jump here to start the next IN combination */
int addrSkip; /* Jump here for next iteration of skip-scan */
int addrCont; /* Jump here to continue with the next loop cycle */
int addrFirst; /* First instruction of interior of the loop */
int addrBody; /* Beginning of the body of this loop */
int regBignull; /* big-null flag reg. True if a NULL-scan is needed */
int addrBignull; /* Jump here for next part of big-null scan */
#ifndef SQLITE_LIKE_DOESNT_MATCH_BLOBS
u32 iLikeRepCntr; /* LIKE range processing counter register (times 2) */
#endif
int regFilter; /* Bloom filter */
WhereRightJoin *pRJ; /* Extra information for RIGHT JOIN */
u8 iFrom; /* Which entry in the FROM clause */
u8 op, p3, p5; /* Opcode, P3 & P5 of the opcode that ends the loop */
int p1, p2; /* Operands of the opcode used to end the loop */
union { /* Information that depends on pWLoop->wsFlags */
struct {
int nIn; /* Number of entries in aInLoop[] */
struct InLoop {
int iCur; /* The VDBE cursor used by this IN operator */
int addrInTop; /* Top of the IN loop */
int iBase; /* Base register of multi-key index record */
int nPrefix; /* Number of prior entries in the key */
u8 eEndLoopOp; /* IN Loop terminator. OP_Next or OP_Prev */
} *aInLoop; /* Information about each nested IN operator */
} in; /* Used when pWLoop->wsFlags&WHERE_IN_ABLE */
Index *pCoveringIdx; /* Possible covering index for WHERE_MULTI_OR */
} u;
struct WhereLoop *pWLoop; /* The selected WhereLoop object */
Bitmask notReady; /* FROM entries not usable at this level */
** 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.u.leftColumn record the
** cursor number and column number for X. WhereTerm.eOperator 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.
**
** A WhereTerm might also be two or more subterms connected by OR:
**
** (t1.X <op> <expr>) OR (t1.Y <op> <expr>) OR ....
**
** In this second case, wtFlag has the TERM_ORINFO bit set and eOperator==WO_OR
** and the WhereTerm.u.pOrInfo field points to auxiliary information that
** is collected about the OR clause.
**
** If a term in the WHERE clause does not match either of the two previous
** categories, then eOperator==0. The WhereTerm.pExpr field is still set
** to the original subexpression content and wtFlags is set up appropriately
** but no other fields in the WhereTerm object are meaningful.
**
** When eOperator!=0, prereqRight and prereqAll record sets of cursor numbers,
** but they do so indirectly. A single WhereMaskSet 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 WhereMaskSet
** 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.
**
** The number of terms in a join is limited by the number of bits
** in prereqRight and prereqAll. The default is 64 bits, hence SQLite
** is only able to process joins with 64 or fewer tables.
*/
struct WhereTerm {
Expr *pExpr; /* Pointer to the subexpression that is this term */
WhereClause *pWC; /* The clause this term is part of */
LogEst truthProb; /* Probability of truth for this expression */
/*
** A WhereTerm with eOperator==WO_AND has its u.pAndInfo pointer set to
** a dynamically allocated instance of the following structure.
*/
struct WhereAndInfo {
WhereClause wc; /* The subexpression broken out */
};
/*
** 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
** SrcItem.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 WhereMaskSet.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 WhereMaskSet 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 WhereMaskSet {
int bVarSelect; /* Used by sqlite3WhereExprUsage() */
int n; /* Number of assigned cursor values */
int ix[BMS]; /* Cursor assigned to each bit */
};
/*
** This object is a convenience wrapper holding all information needed
** to construct WhereLoop objects for a particular query.
*/
struct WhereLoopBuilder {
WhereInfo *pWInfo; /* Information about this WHERE */
WhereClause *pWC; /* WHERE clause terms */
*/
struct WhereInfo {
Parse *pParse; /* Parsing and code generating context */
SrcList *pTabList; /* List of tables in the join */
ExprList *pOrderBy; /* The ORDER BY clause or NULL */
ExprList *pResultSet; /* Result set of the query */
#if WHERETRACE_ENABLED
Expr *pWhere; /* The complete WHERE clause */
#endif
Select *pSelect; /* The entire SELECT statement containing WHERE */
int aiCurOnePass[2]; /* OP_OpenWrite cursors for the ONEPASS opt */
int iContinue; /* Jump here to continue with next record */
int iBreak; /* Jump here to break out of the loop */
int savedNQueryLoop; /* pParse->nQueryLoop outside the WHERE loop */
u16 wctrlFlags; /* Flags originally passed to sqlite3WhereBegin() */
LogEst iLimit; /* LIMIT if wctrlFlags has WHERE_USE_LIMIT */
u8 nLevel; /* Number of nested loop */
i8 nOBSat; /* Number of ORDER BY terms satisfied by indices */
u8 eOnePass; /* ONEPASS_OFF, or _SINGLE, or _MULTI */
u8 eDistinct; /* One of the WHERE_DISTINCT_* values */
unsigned bDeferredSeek :1; /* Uses OP_DeferredSeek */
unsigned untestedTerms :1; /* Not all WHERE terms resolved by outer loop */
unsigned bOrderedInnerLoop:1;/* True if only the inner-most loop is ordered */
unsigned sorted :1; /* True if really sorted (not just grouped) */
LogEst nRowOut; /* Estimated number of output rows */
int iTop; /* The very beginning of the WHERE loop */
int iEndWhere; /* End of the WHERE clause itself */
WhereLoop *pLoops; /* List of all WhereLoop objects */
WhereMemBlock *pMemToFree;/* Memory to free when this object destroyed */
Bitmask revMask; /* Mask of ORDER BY terms that need reversing */
WhereClause sWC; /* Decomposition of the WHERE clause */
WhereMaskSet sMaskSet; /* Map cursor numbers to bitmasks */
WhereLevel a[1]; /* Information about each nest loop in WHERE */
};
/*
** Private interfaces - callable only by other where.c routines.
**
** where.c:
*/
SQLITE_PRIVATE Bitmask sqlite3WhereGetMask(WhereMaskSet*,int);
#ifdef WHERETRACE_ENABLED
** structure.
*/
struct CCurHint {
int iTabCur; /* Cursor for the main table */
int iIdxCur; /* Cursor for the index, if pIdx!=0. Unused otherwise */
Index *pIdx; /* The index used to access the table */
};
/*
** This function is called for every node of an expression that is a candidate
** for a cursor hint on an index cursor. For TK_COLUMN nodes that reference
** the table CCurHint.iTabCur, verify that the same column can be
** accessed through the index. If it cannot, then set pWalker->eCode to 1.
*/
static int codeCursorHintCheckExpr(Walker *pWalker, Expr *pExpr){
struct CCurHint *pHint = pWalker->u.pCCurHint;
assert( pHint->pIdx!=0 );
if( pExpr->op==TK_COLUMN
&& pExpr->iTable==pHint->iTabCur
&& sqlite3TableColumnToIndex(pHint->pIdx, pExpr->iColumn)<0
){
pWalker->eCode = 1;
}
return WRC_Continue;
}
/*
** Test whether or not expression pExpr, which was part of a WHERE clause,
** should be included in the cursor-hint for a table that is on the rhs
** of a LEFT JOIN. Set Walker.eCode to non-zero before returning if the
** expression is not suitable.
**
** An expression is unsuitable if it might evaluate to non NULL even if
** a TK_COLUMN node that does affect the value of the expression is set
** to NULL. For example:
**
** col IS NULL
** col IS NOT NULL
** coalesce(col, 1)
sWalker.pParse = pParse;
sWalker.u.pCCurHint = &sHint;
pWC = &pWInfo->sWC;
for(i=0; i<pWC->nBase; i++){
pTerm = &pWC->a[i];
if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
if( pTerm->prereqAll & pLevel->notReady ) continue;
/* Any terms specified as part of the ON(...) clause for any LEFT
** JOIN for which the current table is not the rhs are omitted
** from the cursor-hint.
**
** If this table is the rhs of a LEFT JOIN, "IS" or "IS NULL" terms
** that were specified as part of the WHERE clause must be excluded.
** This is to address the following:
**
** SELECT ... t1 LEFT JOIN t2 ON (t1.a=t2.b) WHERE t2.c IS NULL;
**
** Say there is a single row in t2 that matches (t1.a=t2.b), but its
** t2.c values is not NULL. If the (t2.c IS NULL) constraint is
** pushed down to the cursor, this row is filtered out, causing
** SQLite to synthesize a row of NULL values. Which does match the
** WHERE clause, and so the query returns a row. Which is incorrect.
**
** For the same reason, WHERE terms such as:
**
** WHERE 1 = (t2.c IS NULL)
**
** are also excluded. See codeCursorHintIsOrFunction() for details.
*/
if( pTabItem->fg.jointype & JT_LEFT ){
sWalker.eCode = 0;
sWalker.xExprCallback = codeCursorHintIsOrFunction;
sqlite3WalkExpr(&sWalker, pTerm->pExpr);
if( sWalker.eCode ) continue;
}
}else{
if( ExprHasProperty(pTerm->pExpr, EP_OuterON) ) continue;
}
/* All terms in pWLoop->aLTerm[] except pEndRange are used to initialize
** the cursor. These terms are not needed as hints for a pure range
** scan (that has no == terms) so omit them. */
if( pLoop->u.btree.nEq==0 && pTerm!=pEndRange ){
for(j=0; j<pLoop->nLTerm && pLoop->aLTerm[j]!=pTerm; j++){}
if( j<pLoop->nLTerm ) continue;
}
/* No subqueries or non-deterministic functions allowed */
if( sqlite3ExprContainsSubquery(pTerm->pExpr) ) continue;
/* For an index scan, make sure referenced columns are actually in
(sHint.pIdx ? sHint.iIdxCur : sHint.iTabCur), 0, 0,
(const char*)pExpr, P4_EXPR);
}
}
#else
# define codeCursorHint(A,B,C,D) /* No-op */
#endif /* SQLITE_ENABLE_CURSOR_HINTS */
/*
** Cursor iCur is open on an intkey b-tree (a table). Register iRowid contains
** a rowid value just read from cursor iIdxCur, open on index pIdx. This
** function generates code to do a deferred seek of cursor iCur to the
** rowid stored in register iRowid.
**
** Normally, this is just:
**
** OP_DeferredSeek $iCur $iRowid
**
** Which causes a seek on $iCur to the row with rowid $iRowid.
**
** However, if the scan currently being coded is a branch of an OR-loop and
** the statement currently being coded is a SELECT, then additional information
** is added that might allow OP_Column to omit the seek and instead do its
** lookup on the index, thus avoiding an expensive seek operation. To
** enable this optimization, the P3 of OP_DeferredSeek is set to iIdxCur
** and P4 is set to an array of integers containing one entry for each column
** in the table. For each table column, if the column is the i'th
** column of the index, then the corresponding array entry is set to (i+1).
** If the column does not appear in the index at all, the array entry is set
** to 0. The OP_Column opcode can check this array to see if the column it
** wants is in the index and if it is, it will substitute the index cursor
** and column number and continue with those new values, rather than seeking
** the table cursor.
*/
static void codeDeferredSeek(
WhereInfo *pWInfo, /* Where clause context */
Index *pIdx, /* Index scan is using */
int iCur, /* Cursor for IPK b-tree */
int iIdxCur /* Index cursor */
){
Parse *pParse = pWInfo->pParse; /* Parse context */
Vdbe *v = pParse->pVdbe; /* Vdbe to generate code within */
assert( iIdxCur>0 );
assert( pIdx->aiColumn[pIdx->nColumn-1]==-1 );
pWInfo->bDeferredSeek = 1;
sqlite3VdbeAddOp3(v, OP_DeferredSeek, iIdxCur, 0, iCur);
if( (pWInfo->wctrlFlags & (WHERE_OR_SUBCLAUSE|WHERE_RIGHT_JOIN))
*/
SQLITE_PRIVATE Bitmask sqlite3WhereCodeOneLoopStart(
Parse *pParse, /* Parsing context */
Vdbe *v, /* Prepared statement under construction */
WhereInfo *pWInfo, /* Complete information about the WHERE clause */
int iLevel, /* Which level of pWInfo->a[] should be coded */
WhereLevel *pLevel, /* The current level pointer */
Bitmask notReady /* Which tables are currently available */
){
int j, k; /* Loop counters */
int iCur; /* The VDBE cursor for the table */
int addrNxt; /* Where to jump to continue with the next IN case */
int bRev; /* True if we need to scan in reverse order */
WhereLoop *pLoop; /* The WhereLoop object being coded */
WhereClause *pWC; /* Decomposition of the entire WHERE clause */
WhereTerm *pTerm; /* A WHERE clause term */
sqlite3 *db; /* Database connection */
SrcItem *pTabItem; /* FROM clause term being coded */
int addrBrk; /* Jump here to break out of the loop */
int addrHalt; /* addrBrk for the outermost loop */
int addrCont; /* Jump here to continue with next cycle */
u16 nEq = pLoop->u.btree.nEq; /* Number of == or IN terms */
u16 nBtm = pLoop->u.btree.nBtm; /* Length of BTM vector */
u16 nTop = pLoop->u.btree.nTop; /* Length of TOP vector */
int regBase; /* Base register holding constraint values */
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 nConstraint; /* Number of constraint terms */
int iIdxCur; /* The VDBE cursor for the index */
int nExtraReg = 0; /* Number of extra registers needed */
int op; /* Instruction opcode */
char *zStartAff; /* Affinity for start of range constraint */
char *zEndAff = 0; /* Affinity for end of range constraint */
u8 bSeekPastNull = 0; /* True to seek past initial nulls */
u8 bStopAtNull = 0; /* Add condition to terminate at NULLs */
int omitTable; /* True if we use the index only */
int regBignull = 0; /* big-null flag register */
int addrSeekScan = 0; /* Opcode of the OP_SeekScan, if any */
** a forward order scan on a descending index, interchange the
** start and end terms (pRangeStart and pRangeEnd).
*/
if( (nEq<pIdx->nColumn && bRev==(pIdx->aSortOrder[nEq]==SQLITE_SO_ASC)) ){
SWAP(WhereTerm *, pRangeEnd, pRangeStart);
SWAP(u8, bSeekPastNull, bStopAtNull);
SWAP(u8, nBtm, nTop);
}
if( iLevel>0 && (pLoop->wsFlags & WHERE_IN_SEEKSCAN)!=0 ){
/* In case OP_SeekScan is used, ensure that the index cursor does not
** point to a valid row for the first iteration of this loop. */
sqlite3VdbeAddOp1(v, OP_NullRow, iIdxCur);
}
/* 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.
*/
codeCursorHint(pTabItem, pWInfo, pLevel, pRangeEnd);
regBase = codeAllEqualityTerms(pParse,pLevel,bRev,nExtraReg,&zStartAff);
addrNxt = (regBignull ? pLevel->addrBignull : pLevel->addrNxt);
testcase( pRangeStart && (pRangeStart->eOperator & WO_LE)!=0 );
testcase( pRangeStart && (pRangeStart->eOperator & WO_GE)!=0 );
testcase( pRangeEnd && (pRangeEnd->eOperator & WO_LE)!=0 );
testcase( pRangeEnd && (pRangeEnd->eOperator & WO_GE)!=0 );
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 ){
Expr *pRight = pRangeStart->pExpr->pRight;
codeExprOrVector(pParse, pRight, regBase+nEq, nBtm);
whereLikeOptimizationStringFixup(v, pLevel, pRangeStart);
if( (pRangeStart->wtFlags & TERM_VNULL)==0
&& sqlite3ExprCanBeNull(pRight)
){
sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, addrNxt);
VdbeCoverage(v);
start_constraints = 1;
nConstraint++;
}else if( regBignull ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);
start_constraints = 1;
nConstraint++;
}
codeApplyAffinity(pParse, regBase, nConstraint - bSeekPastNull, zStartAff);
if( pLoop->nSkip>0 && nConstraint==pLoop->nSkip ){
/* The skip-scan logic inside the call to codeAllEqualityConstraints()
** above has already left the cursor sitting on the correct row,
** so no further seeking is needed */
}else{
if( regBignull ){
sqlite3VdbeAddOp2(v, OP_Integer, 1, regBignull);
VdbeComment((v, "NULL-scan pass ctr"));
}
if( pLevel->regFilter ){
sqlite3VdbeAddOp4Int(v, OP_Filter, pLevel->regFilter, addrNxt,
regBase, nEq);
VdbeCoverage(v);
endEq = 0;
}
nConstraint++;
}
if( zStartAff ) sqlite3DbNNFreeNN(db, zStartAff);
if( zEndAff ) sqlite3DbNNFreeNN(db, zEndAff);
/* Top of the loop body */
pLevel->p2 = sqlite3VdbeCurrentAddr(v);
/* Check if the index cursor is past the end of the range. */
if( nConstraint ){
if( regBignull ){
/* Except, skip the end-of-range check while doing the NULL-scan */
sqlite3VdbeAddOp2(v, OP_IfNot, regBignull, sqlite3VdbeCurrentAddr(v)+3);
VdbeComment((v, "If NULL-scan 2nd pass"));
VdbeCoverage(v);
}
op = aEndOp[bRev*2 + endEq];
sqlite3VdbeAddOp4Int(v, op, iIdxCur, addrNxt, regBase, nConstraint);
testcase( op==OP_IdxGT ); VdbeCoverageIf(v, op==OP_IdxGT );
testcase( op==OP_IdxGT ); VdbeCoverageIf(v, op==OP_IdxGT );
testcase( op==OP_IdxGE ); VdbeCoverageIf(v, op==OP_IdxGE );
testcase( op==OP_IdxLT ); VdbeCoverageIf(v, op==OP_IdxLT );
testcase( op==OP_IdxLE ); VdbeCoverageIf(v, op==OP_IdxLE );
}
if( (pLoop->wsFlags & WHERE_IN_EARLYOUT)!=0 ){
sqlite3VdbeAddOp3(v, OP_SeekHit, iIdxCur, nEq, nEq);
}
/* Seek the table cursor, if required */
omitTable = (pLoop->wsFlags & WHERE_IDX_ONLY)!=0
&& (pWInfo->wctrlFlags & (WHERE_OR_SUBCLAUSE|WHERE_RIGHT_JOIN))==0;
if( omitTable ){
/* pIdx is a covering index. No need to access the main table. */
}else if( HasRowid(pIdx->pTable) ){
codeDeferredSeek(pWInfo, pIdx, iCur, iIdxCur);
}else if( iCur!=iIdxCur ){
Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable);
iRowidReg = sqlite3GetTempRange(pParse, pPk->nKeyCol);
for(j=0; j<pPk->nKeyCol; j++){
/* Initialize the rowset register to contain NULL. An SQL NULL is
** equivalent to an empty rowset. Or, create an ephemeral index
** capable of holding primary keys in the case of a WITHOUT ROWID.
**
** Also initialize regReturn to contain the address of the instruction
** immediately following the OP_Return at the bottom of the loop. This
** is required in a few obscure LEFT JOIN cases where control jumps
** over the top of the loop into the body of it. In this case the
** correct response for the end-of-loop code (the OP_Return) is to
** fall through to the next instruction, just as an OP_Next does if
** called on an uninitialized cursor.
*/
if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){
if( HasRowid(pTab) ){
regRowset = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset);
}else{
Index *pPk = sqlite3PrimaryKeyIndex(pTab);
regRowset = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, regRowset, pPk->nKeyCol);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
if( jmp1 ) sqlite3VdbeJumpHere(v, jmp1);
/* The pSubWInfo->untestedTerms flag means that this OR term
** contained one or more AND term from a notReady table. The
** terms from the notReady table could not be tested and will
** need to be tested later.
*/
if( pSubWInfo->untestedTerms ) untestedTerms = 1;
/* If all of the OR-connected terms are optimized using the same
** index, and the index is opened using the same cursor number
** by each call to sqlite3WhereBegin() made by this loop, it may
** be possible to use that index as a covering index.
**
** If the call to sqlite3WhereBegin() above resulted in a scan that
** uses an index, and this is either the first OR-connected term
** processed or the index is the same as that used by all previous
** terms, set pCov to the candidate covering index. Otherwise, set
** pCov to NULL to indicate that no candidate covering index will
** be available.
*/
{
/* Case 6: There is no usable index. We must do a complete
** scan of the entire table.
*/
static const u8 aStep[] = { OP_Next, OP_Prev };
static const u8 aStart[] = { OP_Rewind, OP_Last };
assert( bRev==0 || bRev==1 );
if( pTabItem->fg.isRecursive ){
/* Tables marked isRecursive have only a single row that is stored in
** a pseudo-cursor. No need to Rewind or Next such cursors. */
pLevel->op = OP_Noop;
}else{
codeCursorHint(pTabItem, pWInfo, pLevel, 0);
pLevel->op = aStep[bRev];
pLevel->p1 = iCur;
pLevel->p2 = 1 + sqlite3VdbeAddOp2(v, aStart[bRev], iCur, addrHalt);
VdbeCoverageIf(v, bRev==0);
VdbeCoverageIf(v, bRev!=0);
pLevel->p5 = SQLITE_STMTSTATUS_FULLSCAN_STEP;
}
**
** x>A OR (x=A AND y>B) adds: x>=A
**
** The added conjunct can sometimes be helpful in query planning.
**
** CASE 3:
**
** If all subterms are indexable by a single table T, then set
**
** WhereTerm.eOperator = WO_OR
** WhereTerm.u.pOrInfo->indexable |= the cursor number for table T
**
** A subterm is "indexable" if it is of the form
** "T.C <op> <expr>" where C is any column of table T and
** <op> is one of "=", "<", "<=", ">", ">=", "IS NULL", or "IN".
** A subterm is also indexable if it is an AND of two or more
** subsubterms at least one of which is indexable. Indexable AND
** subterms have their eOperator set to WO_AND and they have
** u.pAndInfo set to a dynamically allocated WhereAndTerm object.
**
** From another point of view, "indexable" means that the subterm could
** might be possible to form an IN operator with either table1.column
** or table2.column as the LHS if either is common to every term of
** the OR clause.
**
** Note that terms of the form "table.column1=table.column2" (the
** same table on both sizes of the ==) cannot be optimized.
*/
if( chngToIN ){
int okToChngToIN = 0; /* True if the conversion to IN is valid */
int iColumn = -1; /* Column index on lhs of IN operator */
int iCursor = -1; /* Table cursor common to all terms */
int j = 0; /* Loop counter */
/* Search for a table and column that appears on one side or the
** other of the == operator in every subterm. That table and column
** will be recorded in iCursor and iColumn. There might not be any
** such table and column. Set okToChngToIN if an appropriate table
** and column is found but leave okToChngToIN false if not found.
*/
for(j=0; j<2 && !okToChngToIN; j++){
Expr *pLeft = 0;
}
pS = pS->pPrior;
}
return mask;
}
/*
** Expression pExpr is one operand of a comparison operator that might
** be useful for indexing. This routine checks to see if pExpr appears
** in any index. Return TRUE (1) if pExpr is an indexed term and return
** FALSE (0) if not. If TRUE is returned, also set aiCurCol[0] to the cursor
** number of the table that is indexed and aiCurCol[1] to the column number
** of the column that is indexed, or XN_EXPR (-2) if an expression is being
** indexed.
**
** If pExpr is a TK_COLUMN column reference, then this routine always returns
** true even if that particular column is not indexed, because the column
** might be added to an automatic index later.
*/
static SQLITE_NOINLINE int exprMightBeIndexed2(
SrcList *pFrom, /* The FROM clause */
int *aiCurCol, /* Write the referenced table cursor and column here */
Expr *pExpr, /* An operand of a comparison operator */
int j /* Start looking with the j-th pFrom entry */
){
Index *pIdx;
int i;
int iCur;
do{
iCur = pFrom->a[j].iCursor;
for(pIdx=pFrom->a[j].pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->aColExpr==0 ) continue;
aiCurCol[1] = XN_EXPR;
return 1;
}
}
}
}while( ++j < pFrom->nSrc );
return 0;
}
static int exprMightBeIndexed(
SrcList *pFrom, /* The FROM clause */
int *aiCurCol, /* Write the referenced table cursor & column here */
Expr *pExpr, /* An operand of a comparison operator */
int op /* The specific comparison operator */
){
int i;
/* If this expression is a vector to the left or right of a
** inequality constraint (>, <, >= or <=), perform the processing
** on the first element of the vector. */
assert( TK_GT+1==TK_LE && TK_GT+2==TK_LT && TK_GT+3==TK_GE );
assert( TK_IS<TK_GE && TK_ISNULL<TK_GE && TK_IN<TK_GE );
}
/*
** Return ONEPASS_OFF (0) if an UPDATE or DELETE statement is unable to
** operate directly on the rowids returned by a WHERE clause. Return
** ONEPASS_SINGLE (1) if the statement can operation directly because only
** a single row is to be changed. Return ONEPASS_MULTI (2) if the one-pass
** optimization can be used on multiple
**
** If the ONEPASS optimization is used (if this routine returns true)
** then also write the indices of open cursors used by ONEPASS
** into aiCur[0] and aiCur[1]. iaCur[0] gets the cursor of the data
** table and iaCur[1] gets the cursor used by an auxiliary index.
** Either value may be -1, indicating that cursor is not used.
** Any cursors returned will have been opened for writing.
**
** aiCur[0] and aiCur[1] both get -1 if the where-clause logic is
** unable to use the ONEPASS optimization.
*/
SQLITE_PRIVATE int sqlite3WhereOkOnePass(WhereInfo *pWInfo, int *aiCur){
memcpy(aiCur, pWInfo->aiCurOnePass, sizeof(int)*2);
#ifdef WHERETRACE_ENABLED
if( sqlite3WhereTrace && pWInfo->eOnePass!=ONEPASS_OFF ){
sqlite3DebugPrintf("%s cursors: %d %d\n",
pWInfo->eOnePass==ONEPASS_SINGLE ? "ONEPASS_SINGLE" : "ONEPASS_MULTI",
aiCur[0], aiCur[1]);
}
#endif
return pWInfo->eOnePass;
}
/*
** Return TRUE if the WHERE loop uses the OP_DeferredSeek opcode to move
** the data cursor to the row selected by the index cursor.
*/
SQLITE_PRIVATE int sqlite3WhereUsesDeferredSeek(WhereInfo *pWInfo){
return pWInfo->bDeferredSeek;
}
/*
** Move the content of pSrc into pDest
*/
static void whereOrMove(WhereOrSet *pDest, WhereOrSet *pSrc){
pDest->n = pSrc->n;
if( p->rRun<=rRun ) return 0;
}
whereOrInsert_done:
p->prereq = prereq;
p->rRun = rRun;
if( p->nOut>nOut ) p->nOut = nOut;
return 1;
}
/*
** Return the bitmask for the given cursor number. Return 0 if
** iCursor is not in the set.
*/
SQLITE_PRIVATE Bitmask sqlite3WhereGetMask(WhereMaskSet *pMaskSet, int iCursor){
int i;
assert( pMaskSet->n<=(int)sizeof(Bitmask)*8 );
assert( pMaskSet->n>0 || pMaskSet->ix[0]<0 );
assert( iCursor>=-1 );
if( pMaskSet->ix[0]==iCursor ){
return 1;
}
if( pNew && pOld ){
WhereMemBlock *pOldBlk = (WhereMemBlock*)pOld;
pOldBlk--;
assert( pOldBlk->sz<nByte );
memcpy(pNew, pOld, pOldBlk->sz);
}
return pNew;
}
/*
** 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(WhereMaskSet *pMaskSet, int iCursor){
assert( pMaskSet->n < ArraySize(pMaskSet->ix) );
pMaskSet->ix[pMaskSet->n++] = iCursor;
}
/*
}
return 0;
}
/*
** Advance to the next WhereTerm that matches according to the criteria
** established when the pScan object was initialized by whereScanInit().
** Return NULL if there are no more matching WhereTerms.
*/
static WhereTerm *whereScanNext(WhereScan *pScan){
int iCur; /* The cursor on the LHS of the term */
i16 iColumn; /* The column on the LHS of the term. -1 for IPK */
Expr *pX; /* An expression being tested */
WhereClause *pWC; /* Shorthand for pScan->pWC */
WhereTerm *pTerm; /* The term being tested */
int k = pScan->k; /* Where to start scanning */
assert( pScan->iEquiv<=pScan->nEquiv );
pWC = pScan->pWC;
while(1){
iColumn = pScan->aiColumn[pScan->iEquiv-1];
}
/*
** Convert OP_Column opcodes to OP_Copy in previously generated code.
**
** This routine runs over generated VDBE code and translates OP_Column
** opcodes into OP_Copy when the table is being accessed via co-routine
** instead of via table lookup.
**
** If the iAutoidxCur is not zero, then any OP_Rowid instructions on
** cursor iTabCur are transformed into OP_Sequence opcode for the
** iAutoidxCur cursor, in order to generate unique rowids for the
** automatic index being generated.
*/
static void translateColumnToCopy(
Parse *pParse, /* Parsing context */
int iStart, /* Translate from this opcode to the end */
int iTabCur, /* OP_Column/OP_Rowid references to this table */
int iRegister, /* The first column is in this register */
int iAutoidxCur /* If non-zero, cursor of autoindex being generated */
){
Vdbe *v = pParse->pVdbe;
VdbeOp *pOp = sqlite3VdbeGetOp(v, iStart);
int iEnd = sqlite3VdbeCurrentAddr(v);
if( pParse->db->mallocFailed ) return;
for(; iStart<iEnd; iStart++, pOp++){
if( pOp->p1!=iTabCur ) continue;
if( pOp->opcode==OP_Column ){
#ifdef SQLITE_DEBUG
if( pParse->db->flags & SQLITE_VdbeAddopTrace ){
#endif
/*
** Generate code to construct the Index object for an automatic index
** and to set up the WhereLevel object pLevel so that the code generator
** makes use of the automatic index.
*/
static SQLITE_NOINLINE void constructAutomaticIndex(
Parse *pParse, /* The parsing context */
WhereClause *pWC, /* The WHERE clause */
const Bitmask notReady, /* Mask of cursors that are not available */
WhereLevel *pLevel /* Write new index here */
){
int nKeyCol; /* Number of columns in the constructed index */
WhereTerm *pTerm; /* A single term of the WHERE clause */
WhereTerm *pWCEnd; /* End of pWC->a[] */
Index *pIdx; /* Object describing the transient index */
Vdbe *v; /* Prepared statement under construction */
int addrInit; /* Address of the initialization bypass jump */
Table *pTable; /* The table being indexed */
int addrTop; /* Top of the index fill loop */
struct CoveringIndexCheck {
Index *pIdx; /* The index */
int iTabCur; /* Cursor number for the corresponding table */
u8 bExpr; /* Uses an indexed expression */
u8 bUnidx; /* Uses an unindexed column not within an indexed expr */
};
/*
** Information passed in is pWalk->u.pCovIdxCk. Call it pCk.
**
** If the Expr node references the table with cursor pCk->iTabCur, then
** make sure that column is covered by the index pCk->pIdx. We know that
** all columns less than 63 (really BMS-1) are covered, so we don't need
** to check them. But we do need to check any column at 63 or greater.
**
** If the index does not cover the column, then set pWalk->eCode to
** non-zero and return WRC_Abort to stop the search.
**
** If this node does not disprove that the index can be a covering index,
** then just return WRC_Continue, to continue the search.
**
if( pTerm->eOperator & (WO_EQ|WO_IS) ) nLookup -= 19;
}
}
pNew->rRun = sqlite3LogEstAdd(pNew->rRun, nLookup);
}
ApplyCostMultiplier(pNew->rRun, pTab->costMult);
whereLoopOutputAdjust(pWC, pNew, rSize);
if( (pSrc->fg.jointype & JT_RIGHT)!=0 && pProbe->aColExpr ){
/* Do not do an SCAN of a index-on-expression in a RIGHT JOIN
** because the cursor used to access the index might not be
** positioned to the correct row during the right-join no-match
** loop. */
}else{
rc = whereLoopInsert(pBuilder, pNew);
}
pNew->nOut = rSize;
if( rc ) break;
}
}
Walker w;
memset(&w, 0, sizeof(w));
w.pParse = pParse;
w.xExprCallback = exprNodeCanReturnSubtype;
sqlite3WalkExpr(&w, pExpr);
return w.eCode;
}
/*
** The index pIdx is used by a query and contains one or more expressions.
** In other words pIdx is an index on an expression. iIdxCur is the cursor
** number for the index and iDataCur is the cursor number for the corresponding
** table.
**
** This routine adds IndexedExpr entries to the Parse->pIdxEpr field for
** each of the expressions in the index so that the expression code generator
** will know to replace occurrences of the indexed expression with
** references to the corresponding column of the index.
*/
static SQLITE_NOINLINE void whereAddIndexedExpr(
Parse *pParse, /* Add IndexedExpr entries to pParse->pIdxEpr */
Index *pIdx, /* The index-on-expression that contains the expressions */
** 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
** An outer join of tables t1 and t2 is conceptually 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
**
** pOrderBy is a pointer to the ORDER BY clause (or the GROUP BY clause
** if the WHERE_GROUPBY flag is set in wctrlFlags) 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 pOrderBy is NULL.
**
** The iIdxCur parameter is the cursor number of an index. If
** WHERE_OR_SUBCLAUSE is set, iIdxCur is the cursor number of an index
** to use for OR clause processing. The WHERE clause should use this
** specific cursor. If WHERE_ONEPASS_DESIRED is set, then iIdxCur is
** the first cursor in an array of cursors for all indices. iIdxCur should
** be used to compute the appropriate cursor depending on which index is
** used.
*/
SQLITE_PRIVATE WhereInfo *sqlite3WhereBegin(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* FROM clause: A list of all tables to be scanned */
Expr *pWhere, /* The WHERE clause */
ExprList *pOrderBy, /* An ORDER BY (or GROUP BY) clause, or NULL */
ExprList *pResultSet, /* Query result set. Req'd for DISTINCT */
Select *pSelect, /* The entire SELECT statement */
u16 wctrlFlags, /* The WHERE_* flags defined in sqliteInt.h */
int iAuxArg /* If WHERE_OR_SUBCLAUSE is set, index cursor number
** If WHERE_USE_LIMIT, then the limit amount */
){
int nByteWInfo; /* Num. bytes allocated for WhereInfo struct */
int nTabList; /* Number of elements in pTabList */
WhereInfo *pWInfo; /* Will become the return value of this function */
Vdbe *v = pParse->pVdbe; /* The virtual database engine */
Bitmask notReady; /* Cursors that are not yet positioned */
WhereLoopBuilder sWLB; /* The WhereLoop builder */
WhereMaskSet *pMaskSet; /* The expression mask set */
WhereLevel *pLevel; /* A single level in pWInfo->a[] */
*/
testcase( pTabList->nSrc==BMS );
if( pTabList->nSrc>BMS ){
sqlite3ErrorMsg(pParse, "at most %d tables in a join", BMS);
return 0;
}
/* This function normally generates a nested loop for all tables in
** pTabList. But if the WHERE_OR_SUBCLAUSE flag is set, then we should
** only generate code for the first table in pTabList and assume that
** any cursors associated with subsequent tables are uninitialized.
*/
nTabList = (wctrlFlags & WHERE_OR_SUBCLAUSE) ? 1 : pTabList->nSrc;
/* Allocate and initialize the WhereInfo structure that will become the
** return value. A single allocation is used to store the WhereInfo
** struct, the contents of WhereInfo.a[], the WhereClause structure
** and the WhereMaskSet structure. Since WhereClause contains an 8-byte
** field (type Bitmask) it must be aligned on an 8-byte boundary on
** some architectures. Hence the ROUND8() below.
*/
pWInfo->iLimit = iAuxArg;
pWInfo->savedNQueryLoop = pParse->nQueryLoop;
pWInfo->pSelect = pSelect;
memset(&pWInfo->nOBSat, 0,
offsetof(WhereInfo,sWC) - offsetof(WhereInfo,nOBSat));
memset(&pWInfo->a[0], 0, sizeof(WhereLoop)+nTabList*sizeof(WhereLevel));
assert( pWInfo->eOnePass==ONEPASS_OFF ); /* ONEPASS defaults to OFF */
pMaskSet = &pWInfo->sMaskSet;
pMaskSet->n = 0;
pMaskSet->ix[0] = -99; /* Initialize ix[0] to a value that can never be
** a valid cursor number, to avoid an initial
** test for pMaskSet->n==0 in sqlite3WhereGetMask() */
sWLB.pWInfo = pWInfo;
sWLB.pWC = &pWInfo->sWC;
sWLB.pNew = (WhereLoop*)(((char*)pWInfo)+nByteWInfo);
assert( EIGHT_BYTE_ALIGNMENT(sWLB.pNew) );
whereLoopInit(sWLB.pNew);
#ifdef SQLITE_DEBUG
sWLB.pNew->cId = '*';
#endif
for(j=pLevel->u.in.nIn, pIn=&pLevel->u.in.aInLoop[j-1]; j>0; j--, pIn--){
assert( sqlite3VdbeGetOp(v, pIn->addrInTop+1)->opcode==OP_IsNull
|| pParse->db->mallocFailed );
sqlite3VdbeJumpHere(v, pIn->addrInTop+1);
if( pIn->eEndLoopOp!=OP_Noop ){
if( pIn->nPrefix ){
int bEarlyOut =
(pLoop->wsFlags & WHERE_VIRTUALTABLE)==0
&& (pLoop->wsFlags & WHERE_IN_EARLYOUT)!=0;
if( pLevel->iLeftJoin ){
/* For LEFT JOIN queries, cursor pIn->iCur may not have been
** opened yet. This occurs for WHERE clauses such as
** "a = ? AND b IN (...)", where the index is on (a, b). If
** the RHS of the (a=?) is NULL, then the "b IN (...)" may
** never have been coded, but the body of the loop run to
** return the null-row. So, if the cursor is not open yet,
** jump over the OP_Next or OP_Prev instruction about to
** be coded. */
sqlite3VdbeAddOp2(v, OP_IfNotOpen, pIn->iCur,
sqlite3VdbeCurrentAddr(v) + 2 + bEarlyOut);
VdbeCoverage(v);
}
if( bEarlyOut ){
sqlite3VdbeAddOp4Int(v, OP_IfNoHope, pLevel->iIdxCur,
sqlite3VdbeCurrentAddr(v)+2,
pIn->iBase, pIn->nPrefix);
#endif
p->iDataCur = -1;
p->iIdxCur = -1;
}
p = p->pIENext;
}
}
k = pLevel->addrBody + 1;
#ifdef SQLITE_DEBUG
if( db->flags & SQLITE_VdbeAddopTrace ){
printf("TRANSLATE cursor %d->%d in opcode range %d..%d\n",
pLevel->iTabCur, pLevel->iIdxCur, k, last-1);
}
/* Proof that the "+1" on the k value above is safe */
pOp = sqlite3VdbeGetOp(v, k - 1);
assert( pOp->opcode!=OP_Column || pOp->p1!=pLevel->iTabCur );
assert( pOp->opcode!=OP_Rowid || pOp->p1!=pLevel->iTabCur );
assert( pOp->opcode!=OP_IfNullRow || pOp->p1!=pLevel->iTabCur );
#endif
pOp = sqlite3VdbeGetOp(v, k);
pLastOp = pOp + (last - k);
if( pSort && p->pOrderBy && p->pOrderBy->nExpr<=pSort->nExpr ){
int nSave = pSort->nExpr;
pSort->nExpr = p->pOrderBy->nExpr;
if( sqlite3ExprListCompare(pSort, p->pOrderBy, -1)==0 ){
sqlite3ExprListDelete(db, p->pOrderBy);
p->pOrderBy = 0;
}
pSort->nExpr = nSave;
}
/* Assign a cursor number for the ephemeral table used to buffer rows.
** The OpenEphemeral instruction is coded later, after it is known how
** many columns the table will have. */
pMWin->iEphCsr = pParse->nTab++;
pParse->nTab += 3;
selectWindowRewriteEList(pParse, pMWin, pSrc, p->pEList, pTab, &pSublist);
selectWindowRewriteEList(pParse, pMWin, pSrc, p->pOrderBy, pTab, &pSublist);
pMWin->nBufferCol = (pSublist ? pSublist->nExpr : 0);
/* Append the PARTITION BY and ORDER BY expressions to the to the
return res;
}
}
return 0;
}
/*
** This is called by code in select.c before it calls sqlite3WhereBegin()
** to begin iterating through the sub-query results. It is used to allocate
** and initialize registers and cursors used by sqlite3WindowCodeStep().
*/
SQLITE_PRIVATE void sqlite3WindowCodeInit(Parse *pParse, Select *pSelect){
int nEphExpr = pSelect->pSrc->a[0].pSelect->pEList->nExpr;
Window *pMWin = pSelect->pWin;
Window *pWin;
Vdbe *v = sqlite3GetVdbe(pParse);
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pMWin->iEphCsr, nEphExpr);
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+1, pMWin->iEphCsr);
sqlite3VdbeAddOp2(v, OP_OpenDup, pMWin->iEphCsr+2, pMWin->iEphCsr);
** callbacks have been invoked in it.
**
** start,current,end
** Consider a window-frame similar to the following:
**
** (ORDER BY a, b GROUPS BETWEEN 2 PRECEDING AND 2 FOLLOWING)
**
** The windows functions implementation caches the input rows in a temp
** table, sorted by "a, b" (it actually populates the cache lazily, and
** aggressively removes rows once they are no longer required, but that's
** a mere detail). It keeps three cursors open on the temp table. One
** (current) that points to the next row to return to the query engine
** once its window function values have been calculated. Another (end)
** points to the next row to call the xStep() method of each window function
** on (so that it is 2 groups ahead of current). And a third (start) that
** points to the next row to call the xInverse() method of each window
** function on.
**
** Each cursor (start, current and end) consists of a VDBE cursor
** (WindowCsrAndReg.csr) and an array of registers (starting at
** WindowCodeArg.reg) that always contains a copy of the peer values
** read from the corresponding cursor.
**
** Depending on the window-frame in question, all three cursors may not
** be required. In this case both WindowCodeArg.csr and reg are set to
** 0.
*/
struct WindowCodeArg {
Parse *pParse; /* Parse context */
Window *pMWin; /* First in list of functions being processed */
Vdbe *pVdbe; /* VDBE object */
int addrGosub; /* OP_Gosub to this address to return one row */
int regGosub; /* Register used with OP_Gosub(addrGosub) */
int regArg; /* First in array of accumulator registers */
int eDelete; /* See above */
int regRowid;
WindowCsrAndReg start;
WindowCsrAndReg current;
WindowCsrAndReg end;
};
/*
** Generate VM code to read the window frames peer values from cursor csr into
** an array of registers starting at reg.
*/
static void windowReadPeerValues(
WindowCodeArg *p,
int csr,
int reg
){
Window *pMWin = p->pMWin;
ExprList *pOrderBy = pMWin->pOrderBy;
if( pOrderBy ){
**
** Or, if csr is less than zero, then the array of registers at reg is
** already populated with all columns from the current row of the sub-query.
**
** If argument regPartSize is non-zero, then it is a register containing the
** number of rows in the current partition.
*/
static void windowAggStep(
WindowCodeArg *p,
Window *pMWin, /* Linked list of window functions */
int csr, /* Read arguments from this cursor */
int bInverse, /* True to invoke xInverse instead of xStep */
int reg /* Array of registers */
){
Parse *pParse = p->pParse;
Vdbe *v = sqlite3GetVdbe(pParse);
Window *pWin;
for(pWin=pMWin; pWin; pWin=pWin->pNextWin){
FuncDef *pFunc = pWin->pWFunc;
int regArg;
int nArg = pWin->bExprArgs ? 0 : windowArgCount(pWin);
**
** if( csr1.peerVal - regVal <= csr2.peerVal ) goto lbl;
**
** A special type of arithmetic is used such that if csr1.peerVal is not
** a numeric type (real or integer), then the result of the addition
** or subtraction is a a copy of csr1.peerVal.
*/
static void windowCodeRangeTest(
WindowCodeArg *p,
int op, /* OP_Ge, OP_Gt, or OP_Le */
int csr1, /* Cursor number for cursor 1 */
int regVal, /* Register containing non-negative number */
int csr2, /* Cursor number for cursor 2 */
int lbl /* Jump destination if condition is true */
){
Parse *pParse = p->pParse;
Vdbe *v = sqlite3GetVdbe(pParse);
ExprList *pOrderBy = p->pMWin->pOrderBy; /* ORDER BY clause for window */
int reg1 = sqlite3GetTempReg(pParse); /* Reg. for csr1.peerVal+regVal */
int reg2 = sqlite3GetTempReg(pParse); /* Reg. for csr2.peerVal */
int regString = ++pParse->nMem; /* Reg. for constant value '' */
int arith = OP_Add; /* OP_Add or OP_Subtract */
int addrGe; /* Jump destination */
int addrDone = sqlite3VdbeMakeLabel(pParse); /* Address past OP_Ge */
CollSeq *pColl;
/* Read the peer-value from each cursor into a register */
windowReadPeerValues(p, csr1, reg1);
windowReadPeerValues(p, csr2, reg2);
assert( op==OP_Ge || op==OP_Gt || op==OP_Le );
assert( pOrderBy && pOrderBy->nExpr==1 );
if( pOrderBy->a[0].fg.sortFlags & KEYINFO_ORDER_DESC ){
switch( op ){
case OP_Ge: op = OP_Le; break;
case OP_Gt: op = OP_Lt; break;
default: assert( op==OP_Le ); op = OP_Ge; break;
/*
** Helper function for sqlite3WindowCodeStep(). Each call to this function
** generates VM code for a single RETURN_ROW, AGGSTEP or AGGINVERSE
** operation. Refer to the header comment for sqlite3WindowCodeStep() for
** details.
*/
static int windowCodeOp(
WindowCodeArg *p, /* Context object */
int op, /* WINDOW_RETURN_ROW, AGGSTEP or AGGINVERSE */
int regCountdown, /* Register for OP_IfPos countdown */
int jumpOnEof /* Jump here if stepped cursor reaches EOF */
){
int csr, reg;
Parse *pParse = p->pParse;
Window *pMWin = p->pMWin;
int ret = 0;
Vdbe *v = p->pVdbe;
int addrContinue = 0;
int bPeer = (pMWin->eFrmType!=TK_ROWS);
int lblDone = sqlite3VdbeMakeLabel(pParse);
}
}
if( op==WINDOW_RETURN_ROW && pMWin->regStartRowid==0 ){
windowAggFinal(p, 0);
}
addrContinue = sqlite3VdbeCurrentAddr(v);
/* If this is a (RANGE BETWEEN a FOLLOWING AND b FOLLOWING) or
** (RANGE BETWEEN b PRECEDING AND a PRECEDING) frame, ensure the
** start cursor does not advance past the end cursor within the
** temporary table. It otherwise might, if (a>b). Also ensure that,
** if the input cursor is still finding new rows, that the end
** cursor does not go past it to EOF. */
if( pMWin->eStart==pMWin->eEnd && regCountdown
&& pMWin->eFrmType==TK_RANGE
){
int regRowid1 = sqlite3GetTempReg(pParse);
int regRowid2 = sqlite3GetTempReg(pParse);
if( op==WINDOW_AGGINVERSE ){
sqlite3VdbeAddOp2(v, OP_Rowid, p->start.csr, regRowid1);
sqlite3VdbeAddOp2(v, OP_Rowid, p->end.csr, regRowid2);
sqlite3VdbeAddOp3(v, OP_Ge, regRowid2, lblDone, regRowid1);
VdbeCoverage(v);
**
** Other window frame types use variants of the following:
**
** ... loop started by sqlite3WhereBegin() ...
** if( new partition ){
** Gosub flush
** }
** Insert new row into eph table.
**
** if( first row of partition ){
** // Rewind three cursors, all open on the eph table.
** Rewind(csrEnd);
** Rewind(csrStart);
** Rewind(csrCurrent);
**
** regEnd = <expr2> // FOLLOWING expression
** regStart = <expr1> // PRECEDING expression
** }else{
** // First time this branch is taken, the eph table contains two
** // rows. The first row in the partition, which all three cursors
** // currently point to, and the following row.
** AGGSTEP
** if( (regEnd--)<=0 ){
** RETURN_ROW
** if( (regStart--)<=0 ){
** AGGINVERSE
** }
** }
** }
** }
** if( csrCurrent is EOF ) break;
** if( (regStart--)<=0 ){
** AggInverse(csrStart)
** Next(csrStart)
** }
** }
**
** The pseudo-code above uses the following shorthand:
**
** AGGSTEP: invoke the aggregate xStep() function for each window function
** with arguments read from the current row of cursor csrEnd, then
** step cursor csrEnd forward one row (i.e. sqlite3BtreeNext()).
**
** RETURN_ROW: return a row to the caller based on the contents of the
** current row of csrCurrent and the current state of all
** aggregates. Then step cursor csrCurrent forward one row.
**
** AGGINVERSE: invoke the aggregate xInverse() function for each window
** functions with arguments read from the current row of cursor
** csrStart. Then step csrStart forward one row.
**
** There are two other ROWS window frames that are handled significantly
** differently from the above - "BETWEEN <expr> PRECEDING AND <expr> PRECEDING"
** and "BETWEEN <expr> FOLLOWING AND <expr> FOLLOWING". These are special
** cases because they change the order in which the three cursors (csrStart,
** csrCurrent and csrEnd) iterate through the ephemeral table. Cases that
** use UNBOUNDED or CURRENT ROW are much simpler variations on one of these
** three.
**
** ROWS BETWEEN <expr1> PRECEDING AND <expr2> PRECEDING
**
** ... loop started by sqlite3WhereBegin() ...
** if( new partition ){
** Gosub flush
** }
** if( first row of partition ){
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
** regEnd = <expr2>
** regStart = <expr1>
** }else if( new group ){
** ...
** }
** }
**
** 2. Instead of processing a single row, each RETURN_ROW, AGGSTEP or
** AGGINVERSE step processes the current row of the relevant cursor and
** all subsequent rows belonging to the same group.
**
** RANGE window frames are a little different again. As for GROUPS, the
** main loop runs once per group only. And RETURN_ROW, AGGSTEP and AGGINVERSE
** deal in groups instead of rows. As for ROWS and GROUPS, there are three
** basic cases:
**
** RANGE BETWEEN <expr1> PRECEDING AND <expr2> FOLLOWING
**
** ... loop started by sqlite3WhereBegin() ...
** RETURN ROW
** if( csrCurrent is EOF ) break;
** while( csrStart.key + regStart) < csrCurrent.key ){
** AGGINVERSE
** }
** }
** }
**
** In the above notation, "csr.key" means the current value of the ORDER BY
** expression (there is only ever 1 for a RANGE that uses an <expr> FOLLOWING
** or <expr PRECEDING) read from cursor csr.
**
** RANGE BETWEEN <expr1> PRECEDING AND <expr2> PRECEDING
**
** ... loop started by sqlite3WhereBegin() ...
** if( new partition ){
** Gosub flush
** }
** Insert new row into eph table.
** if( first row of partition ){
** Rewind(csrEnd) ; Rewind(csrStart) ; Rewind(csrCurrent)
** <expr>. */
if( pMWin->eStart==TK_PRECEDING || pMWin->eStart==TK_FOLLOWING ){
regStart = ++pParse->nMem;
}
if( pMWin->eEnd==TK_PRECEDING || pMWin->eEnd==TK_FOLLOWING ){
regEnd = ++pParse->nMem;
}
/* If this is not a "ROWS BETWEEN ..." frame, then allocate arrays of
** registers to store copies of the ORDER BY expressions (peer values)
** for the main loop, and for each cursor (start, current and end). */
if( pMWin->eFrmType!=TK_ROWS ){
int nPeer = (pOrderBy ? pOrderBy->nExpr : 0);
regNewPeer = regNew + pMWin->nBufferCol;
if( pMWin->pPartition ) regNewPeer += pMWin->pPartition->nExpr;
regPeer = pParse->nMem+1; pParse->nMem += nPeer;
s.start.reg = pParse->nMem+1; pParse->nMem += nPeer;
s.current.reg = pParse->nMem+1; pParse->nMem += nPeer;
s.end.reg = pParse->nMem+1; pParse->nMem += nPeer;
}
sqlite3_mutex_free(db->mutex);
assert( sqlite3LookasideUsed(db,0)==0 );
if( db->lookaside.bMalloced ){
sqlite3_free(db->lookaside.pStart);
}
sqlite3_free(db);
}
/*
** Rollback all database files. If tripCode is not SQLITE_OK, then
** any write cursors are invalidated ("tripped" - as in "tripping a circuit
** breaker") and made to return tripCode if there are any further
** attempts to use that cursor. Read cursors remain open and valid
** but are "saved" in case the table pages are moved around.
*/
SQLITE_PRIVATE void sqlite3RollbackAll(sqlite3 *db, int tripCode){
int i;
int inTrans = 0;
int schemaChange;
assert( sqlite3_mutex_held(db->mutex) );
sqlite3BeginBenignMalloc();
/* Obtain all b-tree mutexes before making any calls to BtreeRollback().
** 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.
*/
/* #include "sqlite3.h" */
** 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 or 1.
*/
int iVersion;
/*
** Create a new tokenizer. The values in the argv[] array are the
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. *piStartOffset should be set to the index of the first
**
** 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 */
);
/***********************************************************************
** Methods below this point are only available if iVersion>=1.
*/
/*
** Configure the language id of a tokenizer cursor.
*/
int (*xLanguageid)(sqlite3_tokenizer_cursor *pCsr, int iLangid);
};
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 */
};
int fts3_global_term_cnt(int iTerm, int iCol);
int fts3_term_cnt(int iTerm, int iCol);
#endif /* _FTS3_TOKENIZER_H_ */
/************** End of fts3_tokenizer.h **************************************/
/* Macro to find the number of segments to merge */
#if defined(SQLITE_DEBUG) || defined(SQLITE_TEST)
# define MergeCount(P) ((P)->nMergeCount)
#else
# define MergeCount(P) FTS3_MERGE_COUNT
#endif
/*
** When the core wants to read from the virtual table, it creates a
** virtual table cursor (an instance of the following structure) using
** the xOpen method. Cursors are destroyed using the xClose method.
*/
struct Fts3Cursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
i16 eSearch; /* Search strategy (see below) */
u8 isEof; /* True if at End Of Results */
u8 isRequireSeek; /* True if must seek pStmt to %_content row */
u8 bSeekStmt; /* True if pStmt is a seek */
sqlite3_stmt *pStmt; /* Prepared statement in use by the cursor */
Fts3Expr *pExpr; /* Parsed MATCH query string */
int iLangid; /* Language being queried for */
int nPhrase; /* Number of matchable phrases in query */
Fts3DeferredToken *pDeferred; /* Deferred search tokens, if any */
sqlite3_int64 iPrevId; /* Previous id read from aDoclist */
char *pNextId; /* Pointer into the body of aDoclist */
char *aDoclist; /* List of docids for full-text queries */
int nDoclist; /* Size of buffer at aDoclist */
u8 bDesc; /* True to sort in descending order */
int eEvalmode; /* An FTS3_EVAL_XX constant */
char **, int, int, int, const char *, int, Fts3Expr **, char **
);
SQLITE_PRIVATE void sqlite3Fts3ExprFree(Fts3Expr *);
#ifdef SQLITE_TEST
SQLITE_PRIVATE int sqlite3Fts3ExprInitTestInterface(sqlite3 *db, Fts3Hash*);
SQLITE_PRIVATE int sqlite3Fts3InitTerm(sqlite3 *db);
#endif
SQLITE_PRIVATE void *sqlite3Fts3MallocZero(i64 nByte);
SQLITE_PRIVATE int sqlite3Fts3OpenTokenizer(sqlite3_tokenizer *, int, const char *, int,
sqlite3_tokenizer_cursor **
);
/* fts3_aux.c */
SQLITE_PRIVATE int sqlite3Fts3InitAux(sqlite3 *db);
SQLITE_PRIVATE void sqlite3Fts3EvalPhraseCleanup(Fts3Phrase *);
SQLITE_PRIVATE int sqlite3Fts3MsrIncrStart(
Fts3Table*, Fts3MultiSegReader*, int, const char*, int);
SQLITE_PRIVATE int sqlite3Fts3MsrIncrNext(
}
}
assert( p->pSegments==0 );
return SQLITE_OK;
}
/*
** Implementation of xOpen method.
*/
static int fts3OpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
sqlite3_vtab_cursor *pCsr; /* Allocated cursor */
UNUSED_PARAMETER(pVTab);
/* Allocate a buffer large enough for an Fts3Cursor structure. If the
** allocation succeeds, zero it and return SQLITE_OK. Otherwise,
** if the allocation fails, return SQLITE_NOMEM.
*/
*ppCsr = pCsr = (sqlite3_vtab_cursor *)sqlite3_malloc(sizeof(Fts3Cursor));
if( !pCsr ){
return SQLITE_NOMEM;
}
memset(pCsr, 0, sizeof(Fts3Cursor));
return SQLITE_OK;
}
/*
** Finalize the statement handle at pCsr->pStmt.
**
p->pSeekStmt = pCsr->pStmt;
sqlite3_reset(pCsr->pStmt);
pCsr->pStmt = 0;
}
pCsr->bSeekStmt = 0;
}
sqlite3_finalize(pCsr->pStmt);
}
/*
** Free all resources currently held by the cursor passed as the only
** argument.
*/
static void fts3ClearCursor(Fts3Cursor *pCsr){
fts3CursorFinalizeStmt(pCsr);
sqlite3Fts3FreeDeferredTokens(pCsr);
sqlite3_free(pCsr->aDoclist);
sqlite3Fts3MIBufferFree(pCsr->pMIBuffer);
sqlite3Fts3ExprFree(pCsr->pExpr);
memset(&(&pCsr->base)[1], 0, sizeof(Fts3Cursor)-sizeof(sqlite3_vtab_cursor));
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts3CloseMethod(sqlite3_vtab_cursor *pCursor){
Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
fts3ClearCursor(pCsr);
assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** If pCsr->pStmt has not been prepared (i.e. if pCsr->pStmt==0), then
}
finished:
rc2 = sqlite3_reset(pStmt);
if( rc==SQLITE_DONE ) rc = rc2;
return rc;
}
/*
** Set up a cursor object for iterating through a full-text index or a
** single level therein.
*/
SQLITE_PRIVATE int sqlite3Fts3SegReaderCursor(
Fts3Table *p, /* FTS3 table handle */
int iLangid, /* Language-id to search */
int iIndex, /* Index to search (from 0 to p->nIndex-1) */
int iLevel, /* Level of segments to scan */
const char *zTerm, /* Term to query for */
int nTerm, /* Size of zTerm in bytes */
int isPrefix, /* True for a prefix search */
** a pointer to the new Fts3MultiSegReader to *ppSegcsr. Otherwise, return
** an SQLite error code.
**
** It is the responsibility of the caller to free this object by eventually
** passing it to fts3SegReaderCursorFree()
**
** SQLITE_OK is returned if no error occurs, otherwise an SQLite error code.
** Output parameter *ppSegcsr is set to 0 if an error occurs.
*/
static int fts3TermSegReaderCursor(
Fts3Cursor *pCsr, /* Virtual table cursor handle */
const char *zTerm, /* Term to query for */
int nTerm, /* Size of zTerm in bytes */
int isPrefix, /* True for a prefix search */
Fts3MultiSegReader **ppSegcsr /* OUT: Allocated seg-reader cursor */
){
Fts3MultiSegReader *pSegcsr; /* Object to allocate and return */
int rc = SQLITE_NOMEM; /* Return code */
pSegcsr = sqlite3_malloc(sizeof(Fts3MultiSegReader));
if( pSegcsr ){
int i;
int bFound = 0; /* True once an index has been found */
Fts3Table *p = (Fts3Table *)pCsr->base.pVtab;
** prefix) from the database.
*/
static int fts3TermSelect(
Fts3Table *p, /* Virtual table handle */
Fts3PhraseToken *pTok, /* Token to query for */
int iColumn, /* Column to query (or -ve for all columns) */
int *pnOut, /* OUT: Size of buffer at *ppOut */
char **ppOut /* OUT: Malloced result buffer */
){
int rc; /* Return code */
Fts3MultiSegReader *pSegcsr; /* Seg-reader cursor for this term */
TermSelect tsc; /* Object for pair-wise doclist merging */
Fts3SegFilter filter; /* Segment term filter configuration */
pSegcsr = pTok->pSegcsr;
memset(&tsc, 0, sizeof(TermSelect));
filter.flags = FTS3_SEGMENT_IGNORE_EMPTY | FTS3_SEGMENT_REQUIRE_POS
| (pTok->isPrefix ? FTS3_SEGMENT_PREFIX : 0)
| (pTok->bFirst ? FTS3_SEGMENT_FIRST : 0)
| (iColumn<p->nColumn ? FTS3_SEGMENT_COLUMN_FILTER : 0);
nDoc++;
while( (*p++)&0x80 ); /* Skip docid varint */
fts3PoslistCopy(0, &p); /* Skip over position list */
}
}
return nDoc;
}
/*
** Advance the cursor to the next row in the %_content table that
** matches the search criteria. For a MATCH search, this will be
** the next row that matches. For a full-table scan, this will be
** simply the next row in the %_content table. For a docid lookup,
** this routine simply sets the EOF flag.
**
** Return SQLITE_OK if nothing goes wrong. SQLITE_OK is returned
** even if we reach end-of-file. The fts3EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts3NextMethod(sqlite3_vtab_cursor *pCursor){
int rc;
Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
if( pCsr->eSearch==FTS3_DOCID_SEARCH || pCsr->eSearch==FTS3_FULLSCAN_SEARCH ){
Fts3Table *pTab = (Fts3Table*)pCursor->pVtab;
pTab->bLock++;
if( SQLITE_ROW!=sqlite3_step(pCsr->pStmt) ){
pCsr->isEof = 1;
rc = sqlite3_reset(pCsr->pStmt);
}else{
pCsr->iPrevId = sqlite3_column_int64(pCsr->pStmt, 0);
**
** If idxNum==FTS3_DOCID_SEARCH then do a docid lookup for a single entry
** in the %_content table.
**
** If idxNum>=FTS3_FULLTEXT_SEARCH then use the full text index. The
** column on the left-hand side of the MATCH operator is column
** number idxNum-FTS3_FULLTEXT_SEARCH, 0 indexed. argv[0] is the right-hand
** side of the MATCH operator.
*/
static int fts3FilterMethod(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, /* Strategy index */
const char *idxStr, /* Unused */
int nVal, /* Number of elements in apVal */
sqlite3_value **apVal /* Arguments for the indexing scheme */
){
int rc = SQLITE_OK;
char *zSql; /* SQL statement used to access %_content */
int eSearch;
Fts3Table *p = (Fts3Table *)pCursor->pVtab;
Fts3Cursor *pCsr = (Fts3Cursor *)pCursor;
assert( p->pSegments==0 );
/* Collect arguments into local variables */
iIdx = 0;
if( eSearch!=FTS3_FULLSCAN_SEARCH ) pCons = apVal[iIdx++];
if( idxNum & FTS3_HAVE_LANGID ) pLangid = apVal[iIdx++];
if( idxNum & FTS3_HAVE_DOCID_GE ) pDocidGe = apVal[iIdx++];
if( idxNum & FTS3_HAVE_DOCID_LE ) pDocidLe = apVal[iIdx++];
assert( iIdx==nVal );
/* In case the cursor has been used before, clear it now. */
fts3ClearCursor(pCsr);
/* Set the lower and upper bounds on docids to return */
pCsr->iMinDocid = fts3DocidRange(pDocidGe, SMALLEST_INT64);
pCsr->iMaxDocid = fts3DocidRange(pDocidLe, LARGEST_INT64);
if( idxStr ){
pCsr->bDesc = (idxStr[0]=='D');
}else{
pCsr->bDesc = p->bDescIdx;
return rc;
}
rc = fts3EvalStart(pCsr);
sqlite3Fts3SegmentsClose(p);
if( rc!=SQLITE_OK ) return rc;
pCsr->pNextId = pCsr->aDoclist;
pCsr->iPrevId = 0;
}
/* Compile a SELECT statement for this cursor. For a full-table-scan, the
** statement loops through all rows of the %_content table. For a
** full-text query or docid lookup, the statement retrieves a single
** row by docid.
*/
if( eSearch==FTS3_FULLSCAN_SEARCH ){
if( pDocidGe || pDocidLe ){
zSql = sqlite3_mprintf(
"SELECT %s WHERE rowid BETWEEN %lld AND %lld ORDER BY rowid %s",
p->zReadExprlist, pCsr->iMinDocid, pCsr->iMaxDocid,
(pCsr->bDesc ? "DESC" : "ASC")
}
if( rc!=SQLITE_OK ) return rc;
return fts3NextMethod(pCursor);
}
/*
** This is the xEof method of the virtual table. SQLite calls this
** routine to find out if it has reached the end of a result set.
*/
static int fts3EofMethod(sqlite3_vtab_cursor *pCursor){
Fts3Cursor *pCsr = (Fts3Cursor*)pCursor;
if( pCsr->isEof ){
fts3ClearCursor(pCsr);
pCsr->isEof = 1;
}
return pCsr->isEof;
}
/*
** 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 fts3RowidMethod(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
Fts3Cursor *pCsr = (Fts3Cursor *) pCursor;
*pRowid = pCsr->iPrevId;
return SQLITE_OK;
}
/*
** This is the xColumn method, called by SQLite to request a value from
** the row that the supplied cursor currently points to.
**
** If:
**
** (iCol < p->nColumn) -> The value of the iCol'th user column.
** (iCol == p->nColumn) -> Magic column with the same name as the table.
** (iCol == p->nColumn+1) -> Docid column
** (iCol == p->nColumn+2) -> Langid column
*/
static int fts3ColumnMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
int iCol /* Index of column to read value from */
){
int rc = SQLITE_OK; /* Return Code */
Fts3Cursor *pCsr = (Fts3Cursor *) pCursor;
Fts3Table *p = (Fts3Table *)pCursor->pVtab;
/* The column value supplied by SQLite must be in range. */
assert( iCol>=0 && iCol<=p->nColumn+2 );
switch( iCol-p->nColumn ){
case 0:
/* The special 'table-name' column */
sqlite3_result_pointer(pCtx, pCsr, "fts3cursor", 0);
break;
case 1:
/* The docid column */
sqlite3_result_int64(pCtx, pCsr->iPrevId);
break;
case 2:
if( pCsr->pExpr ){
sqlite3_result_int64(pCtx, pCsr->iLangid);
}else if( p->zLanguageid==0 ){
sqlite3_result_int(pCtx, 0);
break;
}else{
iCol = p->nColumn;
/* no break */ deliberate_fall_through
}
default:
/* A user column. Or, if this is a full-table scan, possibly the
** language-id column. Seek the cursor. */
rc = fts3CursorSeek(0, pCsr);
if( rc==SQLITE_OK && sqlite3_data_count(pCsr->pStmt)-1>iCol ){
sqlite3_result_value(pCtx, sqlite3_column_value(pCsr->pStmt, iCol+1));
}
break;
}
assert( ((Fts3Table *)pCsr->base.pVtab)->pSegments==0 );
return rc;
}
** If the value passed as the third argument is a blob of size
** sizeof(Fts3Cursor*), then the blob contents are copied to the
** output variable *ppCsr and SQLITE_OK is returned. Otherwise, an error
** message is written to context pContext and SQLITE_ERROR returned. The
** string passed via zFunc is used as part of the error message.
*/
static int fts3FunctionArg(
sqlite3_context *pContext, /* SQL function call context */
const char *zFunc, /* Function name */
sqlite3_value *pVal, /* argv[0] passed to function */
Fts3Cursor **ppCsr /* OUT: Store cursor handle here */
){
int rc;
*ppCsr = (Fts3Cursor*)sqlite3_value_pointer(pVal, "fts3cursor");
if( (*ppCsr)!=0 ){
rc = SQLITE_OK;
}else{
char *zErr = sqlite3_mprintf("illegal first argument to %s", zFunc);
sqlite3_result_error(pContext, zErr, -1);
sqlite3_free(zErr);
rc = SQLITE_ERROR;
}
return rc;
}
sqlite3Fts3HashClear(&pHash->hash);
sqlite3_free(pHash);
}
return rc;
}
/*
** Allocate an Fts3MultiSegReader for each token in the expression headed
** by pExpr.
**
** An Fts3SegReader object is a cursor that can seek or scan a range of
** entries within a single segment b-tree. An Fts3MultiSegReader uses multiple
** Fts3SegReader objects internally to provide an interface to seek or scan
** within the union of all segments of a b-tree. Hence the name.
**
** If the allocated Fts3MultiSegReader just seeks to a single entry in a
** segment b-tree (if the term is not a prefix or it is a prefix for which
** there exists prefix b-tree of the right length) then it may be traversed
** and merged incrementally. Otherwise, it has to be merged into an in-memory
** doclist and then traversed.
*/
static void fts3EvalAllocateReaders(
Fts3Cursor *pCsr, /* FTS cursor handle */
Fts3Expr *pExpr, /* Allocate readers for this expression */
int *pnToken, /* OUT: Total number of tokens in phrase. */
int *pnOr, /* OUT: Total number of OR nodes in expr. */
int *pRc /* IN/OUT: Error code */
){
if( pExpr && SQLITE_OK==*pRc ){
if( pExpr->eType==FTSQUERY_PHRASE ){
int i;
int nToken = pExpr->pPhrase->nToken;
*pnToken += nToken;
** Assuming no error occurs or has occurred, It returns non-zero if the
** expression passed as the second argument matches the row that pCsr
** currently points to, or zero if it does not.
**
** If *pRc is not SQLITE_OK when this function is called, it is a no-op.
** If an error occurs during execution of this function, *pRc is set to
** the appropriate SQLite error code. In this case the returned value is
** undefined.
*/
static int fts3EvalTestExpr(
Fts3Cursor *pCsr, /* FTS cursor handle */
Fts3Expr *pExpr, /* Expr to test. May or may not be root. */
int *pRc /* IN/OUT: Error code */
){
int bHit = 1; /* Return value */
if( *pRc==SQLITE_OK ){
switch( pExpr->eType ){
case FTSQUERY_NEAR:
case FTSQUERY_AND:
bHit = (
fts3EvalTestExpr(pCsr, pExpr->pLeft, pRc)
break;
}
}
}
return bHit;
}
/*
** This function is called as the second part of each xNext operation when
** iterating through the results of a full-text query. At this point the
** cursor points to a row that matches the query expression, with the
** following caveats:
**
** * Up until this point, "NEAR" operators in the expression have been
** treated as "AND".
**
** * Deferred tokens have not yet been considered.
**
** If *pRc is not SQLITE_OK when this function is called, it immediately
** returns 0. Otherwise, it tests whether or not after considering NEAR
** operators and deferred tokens the current row is still a match for the
}
assert( sqlite3_data_count(pCsr->pStmt)==0 );
fts3EvalNextRow(pCsr, pExpr, &rc);
pCsr->isEof = pExpr->bEof;
pCsr->isRequireSeek = 1;
pCsr->isMatchinfoNeeded = 1;
pCsr->iPrevId = pExpr->iDocid;
}while( pCsr->isEof==0 && sqlite3Fts3EvalTestDeferred(pCsr, &rc) );
}
/* Check if the cursor is past the end of the docid range specified
** by Fts3Cursor.iMinDocid/iMaxDocid. If so, set the EOF flag. */
if( rc==SQLITE_OK && (
(pCsr->bDesc==0 && pCsr->iPrevId>pCsr->iMaxDocid)
|| (pCsr->bDesc!=0 && pCsr->iPrevId<pCsr->iMinDocid)
)){
pCsr->isEof = 1;
}
return rc;
}
pExpr->bEof = 0;
pExpr->bStart = 0;
fts3EvalRestart(pCsr, pExpr->pLeft, pRc);
fts3EvalRestart(pCsr, pExpr->pRight, pRc);
}
}
/*
** After allocating the Fts3Expr.aMI[] array for each phrase in the
** expression rooted at pExpr, the cursor iterates through all rows matched
** by pExpr, calling this function for each row. This function increments
** the values in Fts3Expr.aMI[] according to the position-list currently
** found in Fts3Expr.pPhrase->doclist.pList for each of the phrase
** expression nodes.
*/
static void fts3EvalUpdateCounts(Fts3Expr *pExpr, int nCol){
if( pExpr ){
Fts3Phrase *pPhrase = pExpr->pPhrase;
if( pPhrase && pPhrase->doclist.pList ){
int iCol = 0;
** column of each row of the table.
**
** * If a phrase contains some deferred tokens (and some non-deferred
** tokens), count the potential occurrence identified by considering
** the non-deferred tokens instead of actual phrase occurrences.
**
** * If the phrase is part of a NEAR expression, then only phrase instances
** that meet the NEAR constraint are included in the counts.
*/
SQLITE_PRIVATE int sqlite3Fts3EvalPhraseStats(
Fts3Cursor *pCsr, /* FTS cursor handle */
Fts3Expr *pExpr, /* Phrase expression */
u32 *aiOut /* Array to write results into (see above) */
){
Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
int rc = SQLITE_OK;
int iCol;
if( pExpr->bDeferred && pExpr->pParent->eType!=FTSQUERY_NEAR ){
assert( pCsr->nDoc>0 );
for(iCol=0; iCol<pTab->nColumn; iCol++){
** compression and is terminated by either an 0x01 or 0x00 byte. For example,
** if the requested column contains "a b X c d X X" and the position-list
** for 'X' is requested, the buffer returned may contain:
**
** 0x04 0x05 0x03 0x01 or 0x04 0x05 0x03 0x00
**
** This function works regardless of whether or not the phrase is deferred,
** incremental, or neither.
*/
SQLITE_PRIVATE int sqlite3Fts3EvalPhrasePoslist(
Fts3Cursor *pCsr, /* FTS3 cursor object */
Fts3Expr *pExpr, /* Phrase to return doclist for */
int iCol, /* Column to return position list for */
char **ppOut /* OUT: Pointer to position list */
){
Fts3Phrase *pPhrase = pExpr->pPhrase;
Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
char *pIter;
int iThis;
sqlite3_int64 iDocid;
typedef struct Fts3auxTable Fts3auxTable;
typedef struct Fts3auxCursor Fts3auxCursor;
struct Fts3auxTable {
sqlite3_vtab base; /* Base class used by SQLite core */
Fts3Table *pFts3Tab;
};
struct Fts3auxCursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
Fts3MultiSegReader csr; /* Must be right after "base" */
Fts3SegFilter filter;
char *zStop;
int nStop; /* Byte-length of string zStop */
int iLangid; /* Language id to query */
int isEof; /* True if cursor is at EOF */
sqlite3_int64 iRowid; /* Current rowid */
int iCol; /* Current value of 'col' column */
int nStat; /* Size of aStat[] array */
struct Fts3auxColstats {
sqlite3_int64 nDoc; /* 'documents' values for current csr row */
sqlite3_int64 nOcc; /* 'occurrences' values for current csr row */
} *aStat;
};
}
if( iLangid>=0 ){
pInfo->aConstraintUsage[iLangid].argvIndex = iNext++;
pInfo->estimatedCost--;
}
return SQLITE_OK;
}
/*
** xOpen - Open a cursor.
*/
static int fts3auxOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
Fts3auxCursor *pCsr; /* Pointer to cursor object to return */
UNUSED_PARAMETER(pVTab);
pCsr = (Fts3auxCursor *)sqlite3_malloc(sizeof(Fts3auxCursor));
if( !pCsr ) return SQLITE_NOMEM;
memset(pCsr, 0, sizeof(Fts3auxCursor));
*ppCsr = (sqlite3_vtab_cursor *)pCsr;
return SQLITE_OK;
}
/*
** xClose - Close a cursor.
*/
static int fts3auxCloseMethod(sqlite3_vtab_cursor *pCursor){
Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
sqlite3Fts3SegmentsClose(pFts3);
sqlite3Fts3SegReaderFinish(&pCsr->csr);
sqlite3_free((void *)pCsr->filter.zTerm);
sqlite3_free(pCsr->zStop);
sqlite3_free(pCsr->aStat);
sqlite3_free(pCsr);
return SQLITE_OK;
memset(&aNew[pCsr->nStat], 0,
sizeof(struct Fts3auxColstats) * (nSize - pCsr->nStat)
);
pCsr->aStat = aNew;
pCsr->nStat = nSize;
}
return SQLITE_OK;
}
/*
** xNext - Advance the cursor to the next row, if any.
*/
static int fts3auxNextMethod(sqlite3_vtab_cursor *pCursor){
Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
int rc;
/* Increment our pretend rowid value. */
pCsr->iRowid++;
for(pCsr->iCol++; pCsr->iCol<pCsr->nStat; pCsr->iCol++){
if( pCsr->aStat[pCsr->iCol].nDoc>0 ) return SQLITE_OK;
}
}
pCsr->iCol = 0;
}else{
pCsr->isEof = 1;
}
return rc;
}
/*
** xFilter - Initialize a cursor to point at the start of its data.
*/
static int fts3auxFilterMethod(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, /* Strategy index */
const char *idxStr, /* Unused */
int nVal, /* Number of elements in apVal */
sqlite3_value **apVal /* Arguments for the indexing scheme */
){
Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
Fts3Table *pFts3 = ((Fts3auxTable *)pCursor->pVtab)->pFts3Tab;
int rc;
int isScan = 0;
int iLangVal = 0; /* Language id to query */
iGe = iNext++;
}
if( idxNum & FTS4AUX_LE_CONSTRAINT ){
iLe = iNext++;
}
}
if( iNext<nVal ){
iLangid = iNext++;
}
/* In case this cursor is being reused, close and zero it. */
testcase(pCsr->filter.zTerm);
sqlite3Fts3SegReaderFinish(&pCsr->csr);
sqlite3_free((void *)pCsr->filter.zTerm);
sqlite3_free(pCsr->aStat);
sqlite3_free(pCsr->zStop);
memset(&pCsr->csr, 0, ((u8*)&pCsr[1]) - (u8*)&pCsr->csr);
pCsr->filter.flags = FTS3_SEGMENT_REQUIRE_POS|FTS3_SEGMENT_IGNORE_EMPTY;
if( isScan ) pCsr->filter.flags |= FTS3_SEGMENT_SCAN;
);
if( rc==SQLITE_OK ){
rc = sqlite3Fts3SegReaderStart(pFts3, &pCsr->csr, &pCsr->filter);
}
if( rc==SQLITE_OK ) rc = fts3auxNextMethod(pCursor);
return rc;
}
/*
** xEof - Return true if the cursor is at EOF, or false otherwise.
*/
static int fts3auxEofMethod(sqlite3_vtab_cursor *pCursor){
Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
return pCsr->isEof;
}
/*
** xColumn - Return a column value.
*/
static int fts3auxColumnMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
int iCol /* Index of column to read value from */
){
Fts3auxCursor *p = (Fts3auxCursor *)pCursor;
assert( p->isEof==0 );
switch( iCol ){
case 0: /* term */
sqlite3_result_text(pCtx, p->csr.zTerm, p->csr.nTerm, SQLITE_TRANSIENT);
break;
default: /* languageid */
assert( iCol==4 );
sqlite3_result_int(pCtx, p->iLangid);
break;
}
return SQLITE_OK;
}
/*
** xRowid - Return the current rowid for the cursor.
*/
static int fts3auxRowidMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite_int64 *pRowid /* OUT: Rowid value */
){
Fts3auxCursor *pCsr = (Fts3auxCursor *)pCursor;
*pRowid = pCsr->iRowid;
return SQLITE_OK;
}
/*
** Register the fts3aux module with database connection db. Return SQLITE_OK
** if successful or an error code if sqlite3_create_module() fails.
void *pRet = sqlite3_malloc64(nByte);
if( pRet ) memset(pRet, 0, nByte);
return pRet;
}
SQLITE_PRIVATE int sqlite3Fts3OpenTokenizer(
sqlite3_tokenizer *pTokenizer,
int iLangid,
const char *z,
int n,
sqlite3_tokenizer_cursor **ppCsr
){
sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
sqlite3_tokenizer_cursor *pCsr = 0;
int rc;
rc = pModule->xOpen(pTokenizer, z, n, &pCsr);
assert( rc==SQLITE_OK || pCsr==0 );
if( rc==SQLITE_OK ){
pCsr->pTokenizer = pTokenizer;
if( pModule->iVersion>=1 ){
rc = pModule->xLanguageid(pCsr, iLangid);
if( rc!=SQLITE_OK ){
pModule->xClose(pCsr);
static int getNextToken(
ParseContext *pParse, /* fts3 query parse context */
int iCol, /* Value for Fts3Phrase.iColumn */
const char *z, int n, /* Input string */
Fts3Expr **ppExpr, /* OUT: expression */
int *pnConsumed /* OUT: Number of bytes consumed */
){
sqlite3_tokenizer *pTokenizer = pParse->pTokenizer;
sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
int rc;
sqlite3_tokenizer_cursor *pCursor;
Fts3Expr *pRet = 0;
int i = 0;
/* Set variable i to the maximum number of bytes of input to tokenize. */
for(i=0; i<n; i++){
if( sqlite3_fts3_enable_parentheses && (z[i]=='(' || z[i]==')') ) break;
if( z[i]=='"' ) break;
}
*pnConsumed = i;
*/
static int getNextString(
ParseContext *pParse, /* fts3 query parse context */
const char *zInput, int nInput, /* Input string */
Fts3Expr **ppExpr /* OUT: expression */
){
sqlite3_tokenizer *pTokenizer = pParse->pTokenizer;
sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
int rc;
Fts3Expr *p = 0;
sqlite3_tokenizer_cursor *pCursor = 0;
char *zTemp = 0;
int nTemp = 0;
const int nSpace = sizeof(Fts3Expr) + sizeof(Fts3Phrase);
int nToken = 0;
/* The final Fts3Expr data structure, including the Fts3Phrase,
** Fts3PhraseToken structures token buffers are all stored as a single
** allocation so that the expression can be freed with a single call to
** sqlite3_free(). Setting this up requires a two pass approach.
**
** The first pass, in the block below, uses a tokenizer cursor to iterate
** through the tokens in the expression. This pass uses fts3ReallocOrFree()
** to assemble data in two dynamic buffers:
**
** Buffer p: Points to the Fts3Expr structure, followed by the Fts3Phrase
** structure, followed by the array of Fts3PhraseToken
** structures. This pass only populates the Fts3PhraseToken array.
**
** Buffer zTemp: Contains copies of all tokens.
**
** The second pass, in the block that begins "if( rc==SQLITE_DONE )" below,
/* #include "fts3_tokenizer.h" */
/*
** Class derived from sqlite3_tokenizer
*/
typedef struct porter_tokenizer {
sqlite3_tokenizer base; /* Base class */
} porter_tokenizer;
/*
** Class derived from sqlite3_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;
/*
** Create a new tokenizer instance.
*/
static int porterCreate(
int argc, const char * const *argv,
sqlite3_tokenizer **ppTokenizer
){
porter_tokenizer *t;
/*
** 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;
UNUSED_PARAMETER(pTokenizer);
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
/* 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++;
}
**
*/
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 *azArg[64];
/* #include <stdio.h> */
/* #include <string.h> */
/* #include "fts3_tokenizer.h" */
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;
static int simpleDelim(simple_tokenizer *t, unsigned char c){
return c<0x80 && t->delim[c];
}
static int fts3_isalnum(int x){
return (x>='0' && x<='9') || (x>='A' && x<='Z') || (x>='a' && x<='z');
}
/*
/*
** 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;
UNUSED_PARAMETER(pTokenizer);
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;
/* Scan past delimiter characters */
while( c->iOffset<c->nBytes && simpleDelim(t, p[c->iOffset]) ){
c->iOffset++;
}
/*
** Virtual table structure.
*/
struct Fts3tokTable {
sqlite3_vtab base; /* Base class used by SQLite core */
const sqlite3_tokenizer_module *pMod;
sqlite3_tokenizer *pTok;
};
/*
** Virtual table cursor structure.
*/
struct Fts3tokCursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
char *zInput; /* Input string */
sqlite3_tokenizer_cursor *pCsr; /* Cursor to iterate through zInput */
int iRowid; /* Current 'rowid' value */
const char *zToken; /* Current 'token' value */
int nToken; /* Size of zToken in bytes */
int iStart; /* Current 'start' value */
int iEnd; /* Current 'end' value */
int iPos; /* Current 'pos' value */
};
/*
** Query FTS for the tokenizer implementation named zName.
}
}
pInfo->idxNum = 0;
assert( pInfo->estimatedCost>1000000.0 );
return SQLITE_OK;
}
/*
** xOpen - Open a cursor.
*/
static int fts3tokOpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
Fts3tokCursor *pCsr;
UNUSED_PARAMETER(pVTab);
pCsr = (Fts3tokCursor *)sqlite3_malloc(sizeof(Fts3tokCursor));
if( pCsr==0 ){
return SQLITE_NOMEM;
}
memset(pCsr, 0, sizeof(Fts3tokCursor));
*ppCsr = (sqlite3_vtab_cursor *)pCsr;
return SQLITE_OK;
}
/*
** Reset the tokenizer cursor passed as the only argument. As if it had
** just been returned by fts3tokOpenMethod().
*/
static void fts3tokResetCursor(Fts3tokCursor *pCsr){
if( pCsr->pCsr ){
Fts3tokTable *pTab = (Fts3tokTable *)(pCsr->base.pVtab);
pTab->pMod->xClose(pCsr->pCsr);
pCsr->pCsr = 0;
}
sqlite3_free(pCsr->zInput);
pCsr->zInput = 0;
pCsr->zToken = 0;
pCsr->nToken = 0;
pCsr->iStart = 0;
pCsr->iEnd = 0;
pCsr->iPos = 0;
pCsr->iRowid = 0;
}
/*
** xClose - Close a cursor.
*/
static int fts3tokCloseMethod(sqlite3_vtab_cursor *pCursor){
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
fts3tokResetCursor(pCsr);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** xNext - Advance the cursor to the next row, if any.
*/
static int fts3tokNextMethod(sqlite3_vtab_cursor *pCursor){
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
int rc; /* Return code */
pCsr->iRowid++;
rc = pTab->pMod->xNext(pCsr->pCsr,
&pCsr->zToken, &pCsr->nToken,
&pCsr->iStart, &pCsr->iEnd, &pCsr->iPos
);
if( rc!=SQLITE_OK ){
fts3tokResetCursor(pCsr);
if( rc==SQLITE_DONE ) rc = SQLITE_OK;
}
return rc;
}
/*
** xFilter - Initialize a cursor to point at the start of its data.
*/
static int fts3tokFilterMethod(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, /* Strategy index */
const char *idxStr, /* Unused */
int nVal, /* Number of elements in apVal */
sqlite3_value **apVal /* Arguments for the indexing scheme */
){
int rc = SQLITE_ERROR;
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
Fts3tokTable *pTab = (Fts3tokTable *)(pCursor->pVtab);
UNUSED_PARAMETER(idxStr);
UNUSED_PARAMETER(nVal);
pCsr->pCsr->pTokenizer = pTab->pTok;
}
}
}
if( rc!=SQLITE_OK ) return rc;
return fts3tokNextMethod(pCursor);
}
/*
** xEof - Return true if the cursor is at EOF, or false otherwise.
*/
static int fts3tokEofMethod(sqlite3_vtab_cursor *pCursor){
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
return (pCsr->zToken==0);
}
/*
** xColumn - Return a column value.
*/
static int fts3tokColumnMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
int iCol /* Index of column to read value from */
){
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
/* CREATE TABLE x(input, token, start, end, position) */
switch( iCol ){
case 0:
sqlite3_result_text(pCtx, pCsr->zInput, -1, SQLITE_TRANSIENT);
break;
break;
default:
assert( iCol==4 );
sqlite3_result_int(pCtx, pCsr->iPos);
break;
}
return SQLITE_OK;
}
/*
** xRowid - Return the current rowid for the cursor.
*/
static int fts3tokRowidMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite_int64 *pRowid /* OUT: Rowid value */
){
Fts3tokCursor *pCsr = (Fts3tokCursor *)pCursor;
*pRowid = (sqlite3_int64)pCsr->iRowid;
return SQLITE_OK;
}
/*
** Register the fts3tok module with database connection db. Return SQLITE_OK
** if successful or an error code if sqlite3_create_module() fails.
int nData;
char *aData;
int nSpace;
sqlite3_int64 iLastDocid;
sqlite3_int64 iLastCol;
sqlite3_int64 iLastPos;
};
/*
** Each cursor has a (possibly empty) linked list of the following objects.
*/
struct Fts3DeferredToken {
Fts3PhraseToken *pToken; /* Pointer to corresponding expr token */
int iCol; /* Column token must occur in */
Fts3DeferredToken *pNext; /* Next in list of deferred tokens */
PendingList *pList; /* Doclist is assembled here */
};
/*
** An instance of this structure is used to iterate through the terms on
int iStart = 0;
int iEnd = 0;
int iPos = 0;
int nWord = 0;
char const *zToken;
int nToken = 0;
sqlite3_tokenizer *pTokenizer = p->pTokenizer;
sqlite3_tokenizer_module const *pModule = pTokenizer->pModule;
sqlite3_tokenizer_cursor *pCsr;
int (*xNext)(sqlite3_tokenizer_cursor *pCursor,
const char**,int*,int*,int*,int*);
assert( pTokenizer && pModule );
/* If the user has inserted a NULL value, this function may be called with
** zText==0. In this case, add zero token entries to the hash table and
** return early. */
if( zText==0 ){
*pnWord = 0;
return SQLITE_OK;
);
while( pReader->pBlob && rc==SQLITE_OK
&& (pFrom - pReader->aNode + nByte)>pReader->nPopulate
){
rc = fts3SegReaderIncrRead(pReader);
}
return rc;
}
/*
** Set an Fts3SegReader cursor to point at EOF.
*/
static void fts3SegReaderSetEof(Fts3SegReader *pSeg){
if( !fts3SegReaderIsRootOnly(pSeg) ){
sqlite3_free(pSeg->aNode);
sqlite3_blob_close(pSeg->pBlob);
pSeg->pBlob = 0;
}
pSeg->aNode = 0;
}
rc = rc2;
}
}
}
return rc;
}
/*
** This function opens a cursor used to read the input data for an
** incremental merge operation. Specifically, it opens a cursor to scan
** the oldest nSeg segments (idx=0 through idx=(nSeg-1)) in absolute
** level iAbsLevel.
*/
static int fts3IncrmergeCsr(
Fts3Table *p, /* FTS3 table handle */
sqlite3_int64 iAbsLevel, /* Absolute level to open */
int nSeg, /* Number of segments to merge */
Fts3MultiSegReader *pCsr /* Cursor object to populate */
){
int rc; /* Return Code */
memcpy(&pNode->a[pNode->n], aDoclist, nDoclist);
pNode->n += nDoclist;
}
assert( pNode->n<=pNode->nAlloc );
return SQLITE_OK;
}
/*
** Append the current term and doclist pointed to by cursor pCsr to the
** appendable b-tree segment opened for writing by pWriter.
**
** Return SQLITE_OK if successful, or an SQLite error code otherwise.
*/
static int fts3IncrmergeAppend(
Fts3Table *p, /* Fts3 table handle */
IncrmergeWriter *pWriter, /* Writer object */
Fts3MultiSegReader *pCsr /* Cursor containing term and doclist */
){
const char *zTerm = pCsr->zTerm;
** iAbsLevel.
**
** Each input segment is either removed from the db completely (if all of
** its data was copied to the output segment by the incrmerge operation)
** or modified in place so that it no longer contains those entries that
** have been duplicated in the output segment.
*/
static int fts3IncrmergeChomp(
Fts3Table *p, /* FTS table handle */
sqlite3_int64 iAbsLevel, /* Absolute level containing segments */
Fts3MultiSegReader *pCsr, /* Chomp all segments opened by this cursor */
int *pnRem /* Number of segments not deleted */
){
int i;
int nRem = 0;
int rc = SQLITE_OK;
for(i=pCsr->nSegment-1; i>=0 && rc==SQLITE_OK; i--){
Fts3SegReader *pSeg = 0;
int j;
** Incremental merges happen nMin segments at a time. The segments
** to be merged are the nMin oldest segments (the ones with the smallest
** values for the _segdir.idx field) in the highest level that contains
** at least nMin segments. Multiple merges might occur in an attempt to
** write the quota of nMerge leaf blocks.
*/
SQLITE_PRIVATE int sqlite3Fts3Incrmerge(Fts3Table *p, int nMerge, int nMin){
int rc; /* Return code */
int nRem = nMerge; /* Number of leaf pages yet to be written */
Fts3MultiSegReader *pCsr; /* Cursor used to read input data */
Fts3SegFilter *pFilter; /* Filter used with cursor pCsr */
IncrmergeWriter *pWriter; /* Writer object */
int nSeg = 0; /* Number of input segments */
sqlite3_int64 iAbsLevel = 0; /* Absolute level number to work on */
Blob hint = {0, 0, 0}; /* Hint read from %_stat table */
int bDirtyHint = 0; /* True if blob 'hint' has been modified */
/* Allocate space for the cursor, filter and writer objects */
const int nAlloc = sizeof(*pCsr) + sizeof(*pFilter) + sizeof(*pWriter);
pWriter = (IncrmergeWriter *)sqlite3_malloc64(nAlloc);
if( !pWriter ) return SQLITE_NOMEM;
pFilter = (Fts3SegFilter *)&pWriter[1];
pCsr = (Fts3MultiSegReader *)&pFilter[1];
rc = fts3IncrmergeHintLoad(p, &hint);
while( rc==SQLITE_OK && nRem>0 ){
const i64 nMod = FTS3_SEGDIR_MAXLEVEL * p->nIndex;
sqlite3_stmt *pFindLevel = 0; /* SQL used to determine iAbsLevel */
** nMin segments and no hint in the %_stat table. No work to do.
** Exit early in this case. */
if( nSeg<=0 ) break;
assert( nMod<=0x7FFFFFFF );
if( iAbsLevel<0 || iAbsLevel>(nMod<<32) ){
rc = FTS_CORRUPT_VTAB;
break;
}
/* Open a cursor to iterate through the contents of the oldest nSeg
** indexes of absolute level iAbsLevel. If this cursor is opened using
** the 'hint' parameters, it is possible that there are less than nSeg
** segments available in level iAbsLevel. In this case, no work is
** done on iAbsLevel - fall through to the next iteration of the loop
** to start work on some other level. */
memset(pWriter, 0, nAlloc);
pFilter->flags = FTS3_SEGMENT_REQUIRE_POS;
if( rc==SQLITE_OK ){
rc = fts3IncrmergeOutputIdx(p, iAbsLevel, &iIdx);
assert( bUseHint==1 || bUseHint==0 );
}
while( rc==SQLITE_OK && SQLITE_ROW==sqlite3_step(pStmt) ){
i64 iDocid = sqlite3_column_int64(pStmt, 0);
int iLang = langidFromSelect(p, pStmt);
int iCol;
for(iCol=0; rc==SQLITE_OK && iCol<p->nColumn; iCol++){
if( p->abNotindexed[iCol]==0 ){
const char *zText = (const char *)sqlite3_column_text(pStmt, iCol+1);
sqlite3_tokenizer_cursor *pT = 0;
rc = sqlite3Fts3OpenTokenizer(p->pTokenizer, iLang, zText, -1, &pT);
while( rc==SQLITE_OK ){
char const *zToken; /* Buffer containing token */
int nToken = 0; /* Number of bytes in token */
int iDum1 = 0, iDum2 = 0; /* Dummy variables */
int iPos = 0; /* Position of token in zText */
rc = pModule->xNext(pT, &zToken, &nToken, &iDum1, &iDum2, &iPos);
if( rc==SQLITE_OK ){
Fts3Table *p = (Fts3Table *)pCsr->base.pVtab;
sqlite3_tokenizer *pT = p->pTokenizer;
sqlite3_tokenizer_module const *pModule = pT->pModule;
assert( pCsr->isRequireSeek==0 );
iDocid = sqlite3_column_int64(pCsr->pStmt, 0);
for(i=0; i<p->nColumn && rc==SQLITE_OK; i++){
if( p->abNotindexed[i]==0 ){
const char *zText = (const char *)sqlite3_column_text(pCsr->pStmt, i+1);
sqlite3_tokenizer_cursor *pTC = 0;
rc = sqlite3Fts3OpenTokenizer(pT, pCsr->iLangid, zText, -1, &pTC);
while( rc==SQLITE_OK ){
char const *zToken; /* Buffer containing token */
int nToken = 0; /* Number of bytes in token */
int iDum1 = 0, iDum2 = 0; /* Dummy variables */
int iPos = 0; /* Position of token in zText */
rc = pModule->xNext(pTC, &zToken, &nToken, &iDum1, &iDum2, &iPos);
for(pDef=pCsr->pDeferred; pDef && rc==SQLITE_OK; pDef=pDef->pNext){
*ppData = pRet;
memcpy(pRet, &p->pList->aData[nSkip], *pnData);
return SQLITE_OK;
}
/*
** Add an entry for token pToken to the pCsr->pDeferred list.
*/
SQLITE_PRIVATE int sqlite3Fts3DeferToken(
Fts3Cursor *pCsr, /* Fts3 table cursor */
Fts3PhraseToken *pToken, /* Token to defer */
int iCol /* Column that token must appear in (or -1) */
){
Fts3DeferredToken *pDeferred;
pDeferred = sqlite3_malloc64(sizeof(*pDeferred));
if( !pDeferred ){
return SQLITE_NOMEM;
}
memset(pDeferred, 0, sizeof(*pDeferred));
pDeferred->pToken = pToken;
UNUSED_PARAMETER(iPhrase);
p->nPhrase++;
p->nToken += pPhrase->nToken;
return rc;
}
/*
** Load the doclists for each phrase in the query associated with FTS3 cursor
** pCsr.
**
** If pnPhrase is not NULL, then *pnPhrase is set to the number of matchable
** phrases in the expression (all phrases except those directly or
** indirectly descended from the right-hand-side of a NOT operator). If
** pnToken is not NULL, then it is set to the number of tokens in all
** matchable phrases of the expression.
*/
static int fts3ExprLoadDoclists(
Fts3Cursor *pCsr, /* Fts3 cursor for current query */
int *pnPhrase, /* OUT: Number of phrases in query */
int *pnToken /* OUT: Number of tokens in query */
){
int rc; /* Return Code */
LoadDoclistCtx sCtx = {0,0,0}; /* Context for sqlite3Fts3ExprIterate() */
sCtx.pCsr = pCsr;
rc = sqlite3Fts3ExprIterate(pCsr->pExpr,fts3ExprLoadDoclistsCb,(void*)&sCtx);
if( pnPhrase ) *pnPhrase = sCtx.nPhrase;
if( pnToken ) *pnToken = sCtx.nToken;
return rc;
** nDesired tokens to the right of the snippet. If so, *piPos and
** *pHlMask are updated to shift the snippet nDesired tokens to the
** right. Otherwise, the snippet is shifted by the number of tokens
** available.
*/
if( nDesired>0 ){
int nShift; /* Number of tokens to shift snippet by */
int iCurrent = 0; /* Token counter */
int rc; /* Return Code */
sqlite3_tokenizer_module *pMod;
sqlite3_tokenizer_cursor *pC;
pMod = (sqlite3_tokenizer_module *)pTab->pTokenizer->pModule;
/* Open a cursor on zDoc/nDoc. Check if there are (nSnippet+nDesired)
** or more tokens in zDoc/nDoc.
*/
rc = sqlite3Fts3OpenTokenizer(pTab->pTokenizer, iLangid, zDoc, nDoc, &pC);
if( rc!=SQLITE_OK ){
return rc;
}
while( rc==SQLITE_OK && iCurrent<(nSnippet+nDesired) ){
const char *ZDUMMY; int DUMMY1 = 0, DUMMY2 = 0, DUMMY3 = 0;
rc = pMod->xNext(pC, &ZDUMMY, &DUMMY1, &DUMMY2, &DUMMY3, &iCurrent);
}
if( nShift>0 ){
*piPos += nShift;
*pHlmask = hlmask >> nShift;
}
}
}
return SQLITE_OK;
}
/*
** Extract the snippet text for fragment pFragment from cursor pCsr and
** append it to string buffer pOut.
*/
static int fts3SnippetText(
Fts3Cursor *pCsr, /* FTS3 Cursor */
SnippetFragment *pFragment, /* Snippet to extract */
int iFragment, /* Fragment number */
int isLast, /* True for final fragment in snippet */
int nSnippet, /* Number of tokens in extracted snippet */
const char *zOpen, /* String inserted before highlighted term */
const char *zClose, /* String inserted after highlighted term */
int rc; /* Return code */
const char *zDoc; /* Document text to extract snippet from */
int nDoc; /* Size of zDoc in bytes */
int iCurrent = 0; /* Current token number of document */
int iEnd = 0; /* Byte offset of end of current token */
int isShiftDone = 0; /* True after snippet is shifted */
int iPos = pFragment->iPos; /* First token of snippet */
u64 hlmask = pFragment->hlmask; /* Highlight-mask for snippet */
int iCol = pFragment->iCol+1; /* Query column to extract text from */
sqlite3_tokenizer_module *pMod; /* Tokenizer module methods object */
sqlite3_tokenizer_cursor *pC; /* Tokenizer cursor open on zDoc/nDoc */
zDoc = (const char *)sqlite3_column_text(pCsr->pStmt, iCol);
if( zDoc==0 ){
if( sqlite3_column_type(pCsr->pStmt, iCol)!=SQLITE_NULL ){
return SQLITE_NOMEM;
}
return SQLITE_OK;
}
nDoc = sqlite3_column_bytes(pCsr->pStmt, iCol);
/* Open a token cursor on the document. */
pMod = (sqlite3_tokenizer_module *)pTab->pTokenizer->pModule;
rc = sqlite3Fts3OpenTokenizer(pTab->pTokenizer, pCsr->iLangid, zDoc,nDoc,&pC);
if( rc!=SQLITE_OK ){
return rc;
}
while( rc==SQLITE_OK ){
const char *ZDUMMY; /* Dummy argument used with tokenizer */
int DUMMY1 = -1; /* Dummy argument used with tokenizer */
int iBegin = 0; /* Offset in zDoc of start of token */
** If bGlobal is true, then populate all fields of the matchinfo() output.
** If it is false, then assume that those fields that do not change between
** rows (i.e. FTS3_MATCHINFO_NPHRASE, NCOL, NDOC, AVGLENGTH and part of HITS)
** have already been populated.
**
** Return SQLITE_OK if successful, or an SQLite error code if an error
** occurs. If a value other than SQLITE_OK is returned, the state the
** pInfo->aMatchinfo[] buffer is left in is undefined.
*/
static int fts3MatchinfoValues(
Fts3Cursor *pCsr, /* FTS3 cursor object */
int bGlobal, /* True to grab the global stats */
MatchInfo *pInfo, /* Matchinfo context object */
const char *zArg /* Matchinfo format string */
){
int rc = SQLITE_OK;
int i;
Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
sqlite3_stmt *pSelect = 0;
for(i=0; rc==SQLITE_OK && zArg[i]; i++){
rc = SQLITE_NOMEM;
goto offsets_out;
}
sCtx.iDocid = pCsr->iPrevId;
sCtx.pCsr = pCsr;
/* Loop through the table columns, appending offset information to
** string-buffer res for each column.
*/
for(iCol=0; iCol<pTab->nColumn; iCol++){
sqlite3_tokenizer_cursor *pC; /* Tokenizer cursor */
const char *ZDUMMY; /* Dummy argument used with xNext() */
int NDUMMY = 0; /* Dummy argument used with xNext() */
int iStart = 0;
int iEnd = 0;
int iCurrent = 0;
const char *zDoc;
int nDoc;
/* Initialize the contents of sCtx.aTerm[] for column iCol. This
** operation may fail if the database contains corrupt records.
sqlite3_result_text(pCtx, res.z, res.n-1, sqlite3_free);
}
return;
}
/*
** Implementation of matchinfo() function.
*/
SQLITE_PRIVATE void sqlite3Fts3Matchinfo(
sqlite3_context *pContext, /* Function call context */
Fts3Cursor *pCsr, /* FTS3 table cursor */
const char *zArg /* Second arg to matchinfo() function */
){
Fts3Table *pTab = (Fts3Table *)pCsr->base.pVtab;
const char *zFormat;
if( zArg ){
zFormat = zArg;
}else{
zFormat = FTS3_MATCHINFO_DEFAULT;
}
*zOut++ = 0xF0 + (u8)((c>>18) & 0x07); \
*zOut++ = 0x80 + (u8)((c>>12) & 0x3F); \
*zOut++ = 0x80 + (u8)((c>>6) & 0x3F); \
*zOut++ = 0x80 + (u8)(c & 0x3F); \
} \
}
#endif /* ifndef SQLITE_AMALGAMATION */
typedef struct unicode_tokenizer unicode_tokenizer;
typedef struct unicode_cursor unicode_cursor;
struct unicode_tokenizer {
sqlite3_tokenizer base;
int eRemoveDiacritic;
int nException;
int *aiException;
};
struct unicode_cursor {
sqlite3_tokenizer_cursor base;
const unsigned char *aInput; /* Input text being tokenized */
int nInput; /* Size of aInput[] in bytes */
int iOff; /* Current offset within aInput[] */
int iToken; /* Index of next token to be returned */
char *zToken; /* storage for current token */
int nAlloc; /* space allocated at zToken */
};
/*
if( rc!=SQLITE_OK ){
unicodeDestroy((sqlite3_tokenizer *)pNew);
pNew = 0;
}
*pp = (sqlite3_tokenizer *)pNew;
return rc;
}
/*
** 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 unicodeOpen(
sqlite3_tokenizer *p, /* The tokenizer */
const char *aInput, /* Input string */
int nInput, /* Size of string aInput in bytes */
sqlite3_tokenizer_cursor **pp /* OUT: New cursor object */
){
unicode_cursor *pCsr;
pCsr = (unicode_cursor *)sqlite3_malloc(sizeof(unicode_cursor));
if( pCsr==0 ){
return SQLITE_NOMEM;
}
memset(pCsr, 0, sizeof(unicode_cursor));
pCsr->aInput = (const unsigned char *)aInput;
if( aInput==0 ){
pCsr->nInput = 0;
pCsr->aInput = (const unsigned char*)"";
}else if( nInput<0 ){
pCsr->nInput = (int)strlen(aInput);
}else{
pCsr->nInput = nInput;
}
*pp = &pCsr->base;
UNUSED_PARAMETER(p);
return SQLITE_OK;
}
/*
** Close a tokenization cursor previously opened by a call to
** simpleOpen() above.
*/
static int unicodeClose(sqlite3_tokenizer_cursor *pCursor){
unicode_cursor *pCsr = (unicode_cursor *) pCursor;
sqlite3_free(pCsr->zToken);
sqlite3_free(pCsr);
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 unicodeNext(
sqlite3_tokenizer_cursor *pC, /* Cursor returned by simpleOpen */
const char **paToken, /* OUT: Token text */
int *pnToken, /* OUT: Number of bytes at *paToken */
int *piStart, /* OUT: Starting offset of token */
int *piEnd, /* OUT: Ending offset of token */
int *piPos /* OUT: Position integer of token */
){
unicode_cursor *pCsr = (unicode_cursor *)pC;
unicode_tokenizer *p = ((unicode_tokenizer *)pCsr->base.pTokenizer);
unsigned int iCode = 0;
char *zOut;
const unsigned char *z = &pCsr->aInput[pCsr->iOff];
const unsigned char *zStart = z;
const unsigned char *zEnd;
const unsigned char *zTerm = &pCsr->aInput[pCsr->nInput];
/* Scan past any delimiter characters before the start of the next token.
** Return SQLITE_DONE early if this takes us all the way to the end of
pCsr->nAlloc += 64;
}
/* Write the folded case of the last character read to the output */
zEnd = z;
iOut = sqlite3FtsUnicodeFold((int)iCode, p->eRemoveDiacritic);
if( iOut ){
WRITE_UTF8(zOut, iOut);
}
/* If the cursor is not at EOF, read the next character */
if( z>=zTerm ) break;
READ_UTF8(z, zTerm, iCode);
}while( unicodeIsAlnum(p, (int)iCode)
|| sqlite3FtsUnicodeIsdiacritic((int)iCode)
);
/* Set the output variables and return. */
pCsr->iOff = (int)(z - pCsr->aInput);
*paToken = pCsr->zToken;
*pnToken = (int)(zOut - pCsr->zToken);
struct JsonParent {
u32 iHead; /* Start of object or array */
u32 iValue; /* Start of the value */
u32 iEnd; /* First byte past the end */
u32 nPath; /* Length of path */
i64 iKey; /* Key for JSONB_ARRAY */
};
typedef struct JsonEachCursor JsonEachCursor;
struct JsonEachCursor {
sqlite3_vtab_cursor base; /* Base class - must be first */
u32 iRowid; /* The rowid */
u32 i; /* Index in sParse.aBlob[] of current row */
u32 iEnd; /* EOF when i equals or exceeds this value */
u32 nRoot; /* Size of the root path in bytes */
u8 eType; /* Type of the container for element i */
u8 bRecursive; /* True for json_tree(). False for json_each() */
u32 nParent; /* Current nesting depth */
u32 nParentAlloc; /* Space allocated for aParent[] */
JsonParent *aParent; /* Parent elements of i */
sqlite3 *db; /* Database connection */
}
/* destructor for json_each virtual table */
static int jsonEachDisconnect(sqlite3_vtab *pVtab){
JsonEachConnection *p = (JsonEachConnection*)pVtab;
sqlite3DbFree(p->db, pVtab);
return SQLITE_OK;
}
/* constructor for a JsonEachCursor object for json_each(). */
static int jsonEachOpenEach(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
JsonEachConnection *pVtab = (JsonEachConnection*)p;
JsonEachCursor *pCur;
UNUSED_PARAMETER(p);
pCur = sqlite3DbMallocZero(pVtab->db, sizeof(*pCur));
if( pCur==0 ) return SQLITE_NOMEM;
pCur->db = pVtab->db;
jsonStringZero(&pCur->path);
*ppCursor = &pCur->base;
return SQLITE_OK;
}
/* constructor for a JsonEachCursor object for json_tree(). */
static int jsonEachOpenTree(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
int rc = jsonEachOpenEach(p, ppCursor);
if( rc==SQLITE_OK ){
JsonEachCursor *pCur = (JsonEachCursor*)*ppCursor;
pCur->bRecursive = 1;
}
return rc;
}
/* Reset a JsonEachCursor back to its original state. Free any memory
** held. */
p->iRowid = 0;
p->i = 0;
p->aParent = 0;
p->nParent = 0;
p->nParentAlloc = 0;
p->iEnd = 0;
p->eType = 0;
}
/* Destructor for a jsonEachCursor object */
static int jsonEachClose(sqlite3_vtab_cursor *cur){
JsonEachCursor *p = (JsonEachCursor*)cur;
jsonEachCursorReset(p);
sqlite3DbFree(p->db, cur);
return SQLITE_OK;
}
/* Return TRUE if the jsonEachCursor object has been advanced off the end
** of the JSON object */
static int jsonEachEof(sqlite3_vtab_cursor *cur){
JsonEachCursor *p = (JsonEachCursor*)cur;
return p->i >= p->iEnd;
}
/*
** If the cursor is currently pointing at the label of a object entry,
** then return the index of the value. For all other cases, return the
** current pointer position, which is the value.
*/
static int jsonSkipLabel(JsonEachCursor *p){
if( p->eType==JSONB_OBJECT ){
u32 sz = 0;
u32 n = jsonbPayloadSize(&p->sParse, p->i, &sz);
return p->i + n + sz;
}else{
return p->i;
}
}
if( needQuote ){
jsonPrintf(sz+4,&p->path,".\"%.*s\"", sz, z);
}else{
jsonPrintf(sz+2,&p->path,".%.*s", sz, z);
}
}
}
/* Advance the cursor to the next element for json_tree() */
static int jsonEachNext(sqlite3_vtab_cursor *cur){
JsonEachCursor *p = (JsonEachCursor*)cur;
int rc = SQLITE_OK;
if( p->bRecursive ){
u8 x;
u8 levelChange = 0;
u32 n, sz = 0;
u32 i = jsonSkipLabel(p);
x = p->sParse.aBlob[i] & 0x0f;
n = jsonbPayloadSize(&p->sParse, i, &sz);
if( x==JSONB_OBJECT || x==JSONB_ARRAY ){
if( JSON_LOOKUP_ISERROR(x) ) continue;
if( x + jsonbPayloadSize(&p->sParse, x, &sz) == p->i ) break;
}
}
}
return n;
}
/* Return the value of a column */
static int jsonEachColumn(
sqlite3_vtab_cursor *cur, /* The cursor */
sqlite3_context *ctx, /* First argument to sqlite3_result_...() */
int iColumn /* Which column to return */
){
JsonEachCursor *p = (JsonEachCursor*)cur;
switch( iColumn ){
case JEACH_KEY: {
if( p->nParent==0 ){
u32 n, j;
if( p->nRoot==1 ) break;
j = jsonEachPathLength(p);
}else{
sqlite3_result_text(ctx, p->sParse.zJson, -1, SQLITE_TRANSIENT);
}
break;
}
}
return SQLITE_OK;
}
/* Return the current rowid value */
static int jsonEachRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
JsonEachCursor *p = (JsonEachCursor*)cur;
*pRowid = p->iRowid;
return SQLITE_OK;
}
/* The query strategy is to look for an equality constraint on the json
** column. Without such a constraint, the table cannot operate. idxNum is
** 1 if the constraint is found, 3 if the constraint and zRoot are found,
** and 0 otherwise.
*/
pIdxInfo->aConstraintUsage[i].argvIndex = 2;
pIdxInfo->aConstraintUsage[i].omit = 1;
pIdxInfo->idxNum = 3; /* Both JSON and ROOT are supplied. Plan 3 */
}
}
return SQLITE_OK;
}
/* Start a search on a new JSON string */
static int jsonEachFilter(
sqlite3_vtab_cursor *cur,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
JsonEachCursor *p = (JsonEachCursor*)cur;
const char *zRoot = 0;
u32 i, n, sz;
UNUSED_PARAMETER(idxStr);
UNUSED_PARAMETER(argc);
jsonEachCursorReset(p);
}
/* The methods of the json_each virtual table */
static sqlite3_module jsonEachModule = {
0, /* iVersion */
0, /* xCreate */
jsonEachConnect, /* xConnect */
jsonEachBestIndex, /* xBestIndex */
jsonEachDisconnect, /* xDisconnect */
0, /* xDestroy */
jsonEachOpenEach, /* xOpen - open a cursor */
jsonEachClose, /* xClose - close a cursor */
jsonEachFilter, /* xFilter - configure scan constraints */
jsonEachNext, /* xNext - advance a cursor */
jsonEachEof, /* xEof - check for end of scan */
jsonEachColumn, /* xColumn - read data */
jsonEachRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
};
/* The methods of the json_tree virtual table. */
static sqlite3_module jsonTreeModule = {
0, /* iVersion */
0, /* xCreate */
jsonEachConnect, /* xConnect */
jsonEachBestIndex, /* xBestIndex */
jsonEachDisconnect, /* xDisconnect */
0, /* xDestroy */
jsonEachOpenTree, /* xOpen - open a cursor */
jsonEachClose, /* xClose - close a cursor */
jsonEachFilter, /* xFilter - configure scan constraints */
jsonEachNext, /* xNext - advance a cursor */
jsonEachEof, /* xEof - check for end of scan */
jsonEachColumn, /* xColumn - read data */
jsonEachRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
#endif
#ifdef SQLITE_DEBUG
u8 bCorrupt; /* Shadow table corruption detected */
#endif
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 */
char *zNodeName; /* Name of the %_node table */
u32 nBusy; /* Current number of users of this structure */
i64 nRowEst; /* Estimated number of rows in this table */
u32 nCursor; /* Number of open cursors */
u32 nNodeRef; /* Number RtreeNodes with positive nRef */
char *zReadAuxSql; /* SQL for statement to read aux data */
/* 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;
** The smallest possible node-size is (512-64)==448 bytes. And the largest
** supported cell size is 48 bytes (8 byte rowid + ten 4 byte coordinates).
** Therefore all non-root nodes must contain at least 3 entries. Since
** 3^40 is greater than 2^64, an r-tree structure always has a depth of
** 40 or less.
*/
#define RTREE_MAX_DEPTH 40
/*
** Number of entries in the cursor RtreeNode cache. The first entry is
** used to cache the RtreeNode for RtreeCursor.sPoint. The remaining
** entries cache the RtreeNode for the first elements of the priority queue.
*/
#define RTREE_CACHE_SZ 5
/*
** An rtree cursor object.
*/
struct RtreeCursor {
sqlite3_vtab_cursor base; /* Base class. Must be first */
u8 atEOF; /* True if at end of search */
u8 bPoint; /* True if sPoint is valid */
u8 bAuxValid; /* True if pReadAux is valid */
int iStrategy; /* Copy of idxNum search parameter */
int nConstraint; /* Number of entries in aConstraint */
RtreeConstraint *aConstraint; /* Search constraints. */
int nPointAlloc; /* Number of slots allocated for aPoint[] */
int nPoint; /* Number of slots used in aPoint[] */
int mxLevel; /* iLevel value for root of the tree */
RtreeSearchPoint *aPoint; /* Priority queue for search points */
/* Possible values for RtreeConstraint.op */
#define RTREE_EQ 0x41 /* A */
#define RTREE_LE 0x42 /* B */
#define RTREE_LT 0x43 /* C */
#define RTREE_GE 0x44 /* D */
#define RTREE_GT 0x45 /* E */
#define RTREE_MATCH 0x46 /* F: Old-style sqlite3_rtree_geometry_callback() */
#define RTREE_QUERY 0x47 /* G: New-style sqlite3_rtree_query_callback() */
/* Special operators available only on cursors. Needs to be consecutive
** with the normal values above, but must be less than RTREE_MATCH. These
** are used in the cursor for contraints such as x=NULL (RTREE_FALSE) or
** x<'xyz' (RTREE_TRUE) */
#define RTREE_TRUE 0x3f /* ? */
#define RTREE_FALSE 0x40 /* @ */
/*
** An rtree structure node.
*/
struct RtreeNode {
RtreeNode *pParent; /* Parent node */
i64 iNode; /* The node number */
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;
Rtree *pRtree = (Rtree *)pVTab;
RtreeCursor *pCsr;
pCsr = (RtreeCursor *)sqlite3_malloc64(sizeof(RtreeCursor));
if( pCsr ){
memset(pCsr, 0, sizeof(RtreeCursor));
pCsr->base.pVtab = pVTab;
rc = SQLITE_OK;
pRtree->nCursor++;
}
*ppCursor = (sqlite3_vtab_cursor *)pCsr;
return rc;
}
/*
** Reset a cursor back to its initial state.
*/
static void resetCursor(RtreeCursor *pCsr){
Rtree *pRtree = (Rtree *)(pCsr->base.pVtab);
int ii;
sqlite3_stmt *pStmt;
if( pCsr->aConstraint ){
int i; /* Used to iterate through constraint array */
for(i=0; i<pCsr->nConstraint; i++){
sqlite3_rtree_query_info *pInfo = pCsr->aConstraint[i].pInfo;
if( pInfo ){
pStmt = pCsr->pReadAux;
memset(pCsr, 0, sizeof(RtreeCursor));
pCsr->base.pVtab = (sqlite3_vtab*)pRtree;
pCsr->pReadAux = pStmt;
}
/*
** Rtree virtual table module xClose method.
*/
static int rtreeClose(sqlite3_vtab_cursor *cur){
Rtree *pRtree = (Rtree *)(cur->pVtab);
RtreeCursor *pCsr = (RtreeCursor *)cur;
assert( pRtree->nCursor>0 );
resetCursor(pCsr);
sqlite3_finalize(pCsr->pReadAux);
sqlite3_free(pCsr);
pRtree->nCursor--;
if( pRtree->nCursor==0 && pRtree->inWrTrans==0 ){
nodeBlobReset(pRtree);
}
return SQLITE_OK;
}
/*
** 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->atEOF;
}
/*
** Convert raw bits from the on-disk RTree record into a coordinate value.
** The on-disk format is big-endian and needs to be converted for little-
** endian platforms. The on-disk record stores integer coordinates if
** eInt is true and it stores 32-bit floating point records if eInt is
** false. a[] is the four bytes of the on-disk record to be decoded.
const RtreeSearchPoint *pB
){
if( pA->rScore<pB->rScore ) return -1;
if( pA->rScore>pB->rScore ) return +1;
if( pA->iLevel<pB->iLevel ) return -1;
if( pA->iLevel>pB->iLevel ) return +1;
return 0;
}
/*
** Interchange two search points in a cursor.
*/
static void rtreeSearchPointSwap(RtreeCursor *p, int i, int j){
RtreeSearchPoint t = p->aPoint[i];
assert( i<j );
p->aPoint[i] = p->aPoint[j];
p->aPoint[j] = t;
i++; j++;
if( i<RTREE_CACHE_SZ ){
if( j>=RTREE_CACHE_SZ ){
nodeRelease(RTREE_OF_CURSOR(p), p->aNode[i]);
id = ii ? pCur->aPoint[0].id : pCur->sPoint.id;
*pRC = nodeAcquire(RTREE_OF_CURSOR(pCur), id, 0, &pCur->aNode[ii]);
}
return pCur->aNode[ii];
}
/*
** Push a new element onto the priority queue
*/
static RtreeSearchPoint *rtreeEnqueue(
RtreeCursor *pCur, /* The cursor */
RtreeDValue rScore, /* Score for the new search point */
u8 iLevel /* Level for the new search point */
){
int i, j;
RtreeSearchPoint *pNew;
if( pCur->nPoint>=pCur->nPointAlloc ){
int nNew = pCur->nPointAlloc*2 + 8;
pNew = sqlite3_realloc64(pCur->aPoint, nNew*sizeof(pCur->aPoint[0]));
if( pNew==0 ) return 0;
pCur->aPoint = pNew;
pNew = pParent;
}
return pNew;
}
/*
** Allocate a new RtreeSearchPoint and return a pointer to it. Return
** NULL if malloc fails.
*/
static RtreeSearchPoint *rtreeSearchPointNew(
RtreeCursor *pCur, /* The cursor */
RtreeDValue rScore, /* Score for the new search point */
u8 iLevel /* Level for the new search point */
){
RtreeSearchPoint *pNew, *pFirst;
pFirst = rtreeSearchPointFirst(pCur);
pCur->anQueue[iLevel]++;
if( pFirst==0
|| pFirst->rScore>rScore
|| (pFirst->rScore==rScore && pFirst->iLevel>iLevel)
){
}else{
break;
}
}
}
}
}
/*
** Continue the search on cursor pCur until the front of the queue
** contains an entry suitable for returning as a result-set row,
** or until the RtreeSearchPoint queue is empty, indicating that the
** query has completed.
*/
static int rtreeStepToLeaf(RtreeCursor *pCur){
RtreeSearchPoint *p;
Rtree *pRtree = RTREE_OF_CURSOR(pCur);
RtreeNode *pNode;
int eWithin;
int rc = SQLITE_OK;
rtreeSearchPointPop(pCur);
}
}
pCur->atEOF = p==0;
return SQLITE_OK;
}
/*
** Rtree virtual table module xNext method.
*/
static int rtreeNext(sqlite3_vtab_cursor *pVtabCursor){
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
int rc = SQLITE_OK;
/* Move to the next entry that matches the configured constraints. */
RTREE_QUEUE_TRACE(pCsr, "POP-Nx:");
if( pCsr->bAuxValid ){
pCsr->bAuxValid = 0;
sqlite3_reset(pCsr->pReadAux);
}
rtreeSearchPointPop(pCsr);
rc = rtreeStepToLeaf(pCsr);
return rc;
}
/*
** Rtree virtual table module xRowid method.
*/
static int rtreeRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *pRowid){
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
RtreeSearchPoint *p = rtreeSearchPointFirst(pCsr);
int rc = SQLITE_OK;
RtreeNode *pNode = rtreeNodeOfFirstSearchPoint(pCsr, &rc);
if( rc==SQLITE_OK && ALWAYS(p) ){
if( p->iCell>=NCELL(pNode) ){
rc = SQLITE_ABORT;
}else{
*pRowid = nodeGetRowid(RTREE_OF_CURSOR(pCsr), pNode, p->iCell);
}
}
return rc;
}
/*
** 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;
RtreeSearchPoint *p = rtreeSearchPointFirst(pCsr);
RtreeCoord c;
int rc = SQLITE_OK;
RtreeNode *pNode = rtreeNodeOfFirstSearchPoint(pCsr, &rc);
if( rc ) return rc;
if( NEVER(p==0) ) return SQLITE_OK;
if( p->iCell>=NCELL(pNode) ) return SQLITE_ABORT;
pCons->pInfo = pInfo;
return SQLITE_OK;
}
SQLITE_PRIVATE int sqlite3IntFloatCompare(i64,double);
/*
** 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;
int iCell = 0;
rtreeReference(pRtree);
/* Reset the cursor to the same state as rtreeOpen() leaves it in. */
resetCursor(pCsr);
pCsr->iStrategy = idxNum;
if( idxNum==1 ){
/* Special case - lookup by rowid. */
RtreeNode *pLeaf; /* Leaf on which the required cell resides */
RtreeSearchPoint *p; /* Search point for the leaf */
i64 iRowid = sqlite3_value_int64(argv[0]);
i64 iNode = 0;
int eType = sqlite3_value_numeric_type(argv[0]);
int nData,
sqlite3_value **aData,
sqlite_int64 *pRowid
){
Rtree *pRtree = (Rtree *)pVtab;
int rc = SQLITE_OK;
RtreeCell cell; /* New cell to insert if nData>1 */
int bHaveRowid = 0; /* Set to 1 after new rowid is determined */
if( pRtree->nNodeRef ){
/* Unable to write to the btree while another cursor is reading from it,
** since the write might do a rebalance which would disrupt the read
** cursor. */
return SQLITE_LOCKED_VTAB;
}
rtreeReference(pRtree);
assert(nData>=1);
memset(&cell, 0, sizeof(cell));
/* Constraint handling. A write operation on an r-tree table may return
** SQLITE_CONSTRAINT for two reasons:
**
/* Forward declaration */
static int rtreeIntegrity(sqlite3_vtab*, const char*, const char*, int, char**);
static sqlite3_module rtreeModule = {
4, /* 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 */
rtreeBeginTransaction, /* xBegin - begin transaction */
rtreeEndTransaction, /* xSync - sync transaction */
rtreeEndTransaction, /* xCommit - commit transaction */
rtreeRollback, /* xRollback - rollback transaction */
0, /* xFindFunction - function overloading */
rtreeRename, /* xRename - rename the table */
** Query plans:
**
** 1 rowid lookup
** 2 search for objects overlapping the same bounding box
** that contains polygon argv[0]
** 3 search for objects overlapping the same bounding box
** that contains polygon argv[0]
** 4 full table scan
*/
static int geopolyFilter(
sqlite3_vtab_cursor *pVtabCursor, /* The cursor to initialize */
int idxNum, /* Query plan */
const char *idxStr, /* Not Used */
int argc, sqlite3_value **argv /* Parameters to the query plan */
){
Rtree *pRtree = (Rtree *)pVtabCursor->pVtab;
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
RtreeNode *pRoot = 0;
int rc = SQLITE_OK;
int iCell = 0;
(void)idxStr;
rtreeReference(pRtree);
/* Reset the cursor to the same state as rtreeOpen() leaves it in. */
resetCursor(pCsr);
pCsr->iStrategy = idxNum;
if( idxNum==1 ){
/* Special case - lookup by rowid. */
RtreeNode *pLeaf; /* Leaf on which the required cell resides */
RtreeSearchPoint *p; /* Search point for the leaf */
i64 iRowid = sqlite3_value_int64(argv[0]);
i64 iNode = 0;
rc = findLeafNode(pRtree, iRowid, &pLeaf, &iNode);
pIdxInfo->idxStr = "fullscan";
pIdxInfo->estimatedCost = 3000000.0;
pIdxInfo->estimatedRows = 100000;
return SQLITE_OK;
}
/*
** GEOPOLY virtual table module xColumn method.
*/
static int geopolyColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
Rtree *pRtree = (Rtree *)cur->pVtab;
RtreeCursor *pCsr = (RtreeCursor *)cur;
RtreeSearchPoint *p = rtreeSearchPointFirst(pCsr);
int rc = SQLITE_OK;
RtreeNode *pNode = rtreeNodeOfFirstSearchPoint(pCsr, &rc);
if( rc ) return rc;
if( p==0 ) return SQLITE_OK;
if( i==0 && sqlite3_vtab_nochange(ctx) ) return SQLITE_OK;
if( i<=pRtree->nAux ){
Rtree *pRtree = (Rtree *)pVtab;
int rc = SQLITE_OK;
RtreeCell cell; /* New cell to insert if nData>1 */
i64 oldRowid; /* The old rowid */
int oldRowidValid; /* True if oldRowid is valid */
i64 newRowid; /* The new rowid */
int newRowidValid; /* True if newRowid is valid */
int coordChange = 0; /* Change in coordinates */
if( pRtree->nNodeRef ){
/* Unable to write to the btree while another cursor is reading from it,
** since the write might do a rebalance which would disrupt the read
** cursor. */
return SQLITE_LOCKED_VTAB;
}
rtreeReference(pRtree);
assert(nData>=1);
oldRowidValid = sqlite3_value_type(aData[0])!=SQLITE_NULL;;
oldRowid = oldRowidValid ? sqlite3_value_int64(aData[0]) : 0;
newRowidValid = nData>1 && sqlite3_value_type(aData[1])!=SQLITE_NULL;
newRowid = newRowidValid ? sqlite3_value_int64(aData[1]) : 0;
cell.iRowid = newRowid;
}
static sqlite3_module geopolyModule = {
3, /* iVersion */
geopolyCreate, /* xCreate - create a table */
geopolyConnect, /* xConnect - connect to an existing table */
geopolyBestIndex, /* 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 */
geopolyFilter, /* xFilter - configure scan constraints */
rtreeNext, /* xNext - advance a cursor */
rtreeEof, /* xEof */
geopolyColumn, /* xColumn - read data */
rtreeRowid, /* xRowid - read data */
geopolyUpdate, /* xUpdate - write data */
rtreeBeginTransaction, /* xBegin - begin transaction */
rtreeEndTransaction, /* xSync - sync transaction */
rtreeEndTransaction, /* xCommit - commit transaction */
rtreeEndTransaction, /* xRollback - rollback transaction */
geopolyFindFunction, /* xFindFunction - function overloading */
rtreeRename, /* xRename - rename the table */
typedef struct IcuTokenizer IcuTokenizer;
typedef struct IcuCursor IcuCursor;
struct IcuTokenizer {
sqlite3_tokenizer base;
char *zLocale;
};
struct IcuCursor {
sqlite3_tokenizer_cursor base;
UBreakIterator *pIter; /* ICU break-iterator object */
int nChar; /* Number of UChar elements in pInput */
UChar *aChar; /* Copy of input using utf-16 encoding */
int *aOffset; /* Offsets of each character in utf-8 input */
int nBuffer;
char *zBuffer;
int iToken;
** Destroy a tokenizer
*/
static int icuDestroy(sqlite3_tokenizer *pTokenizer){
IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
sqlite3_free(p);
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 icuOpen(
sqlite3_tokenizer *pTokenizer, /* The tokenizer */
const char *zInput, /* Input string */
int nInput, /* Length of zInput in bytes */
sqlite3_tokenizer_cursor **ppCursor /* OUT: Tokenization cursor */
){
IcuTokenizer *p = (IcuTokenizer *)pTokenizer;
IcuCursor *pCsr;
const int32_t opt = U_FOLD_CASE_DEFAULT;
UErrorCode status = U_ZERO_ERROR;
int nChar;
UChar32 c;
int iInput = 0;
}
pCsr->pIter = ubrk_open(UBRK_WORD, p->zLocale, pCsr->aChar, iOut, &status);
if( !U_SUCCESS(status) ){
sqlite3_free(pCsr);
return SQLITE_ERROR;
}
pCsr->nChar = iOut;
ubrk_first(pCsr->pIter);
*ppCursor = (sqlite3_tokenizer_cursor *)pCsr;
return SQLITE_OK;
}
/*
** Close a tokenization cursor previously opened by a call to icuOpen().
*/
static int icuClose(sqlite3_tokenizer_cursor *pCursor){
IcuCursor *pCsr = (IcuCursor *)pCursor;
ubrk_close(pCsr->pIter);
sqlite3_free(pCsr->zBuffer);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** Extract the next token from a tokenization cursor.
*/
static int icuNext(
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 */
){
IcuCursor *pCsr = (IcuCursor *)pCursor;
int iStart = 0;
int iEnd = 0;
if( p->rc==SQLITE_OK ){
sqlite3_step(pWriter);
p->rc = resetAndCollectError(pWriter, &p->zErrmsg);
}
}
/*
** This function does the work for an sqlite3rbu_step() call.
**
** The object-iterator (p->objiter) currently points to a valid object,
** and the input cursor (p->objiter.pSelect) currently points to a valid
** input row. Perform whatever processing is required and return.
**
** If no error occurs, SQLITE_OK is returned. Otherwise, an error code
** and message is left in the RBU handle and a copy of the error code
** returned.
*/
static int rbuStep(sqlite3rbu *p){
RbuObjIter *pIter = &p->objiter;
const char *zMask = 0;
int eType = rbuStepType(p, &zMask);
/* Variables populated by statDecodePage(): */
u8 flags; /* Copy of flags byte */
int nCell; /* Number of cells on page */
int nUnused; /* Number of unused bytes on page */
StatCell *aCell; /* Array of parsed cells */
u32 iRightChildPg; /* Right-child page number (or 0) */
int nMxPayload; /* Largest payload of any cell on the page */
};
/* The cursor for scanning the dbstat virtual table */
struct StatCursor {
sqlite3_vtab_cursor base; /* base class. MUST BE FIRST! */
sqlite3_stmt *pStmt; /* Iterates through set of root pages */
u8 isEof; /* After pStmt has returned SQLITE_DONE */
u8 isAgg; /* Aggregate results for each table */
int iDb; /* Schema used for this query */
StatPage aPage[32]; /* Pages in path to current page */
int iPage; /* Current entry in aPage[] */
/* Values to return. */
u32 iPageno; /* Value of 'pageno' column */
)
){
pIdxInfo->orderByConsumed = 1;
pIdxInfo->idxNum |= 0x08;
}
return SQLITE_OK;
}
/*
** Open a new DBSTAT cursor.
*/
static int statOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
StatTable *pTab = (StatTable *)pVTab;
StatCursor *pCsr;
pCsr = (StatCursor *)sqlite3_malloc64(sizeof(StatCursor));
if( pCsr==0 ){
return SQLITE_NOMEM_BKPT;
}else{
memset(pCsr, 0, sizeof(StatCursor));
pCsr->base.pVtab = pVTab;
pCsr->iDb = pTab->iDb;
}
*ppCursor = (sqlite3_vtab_cursor *)pCsr;
return SQLITE_OK;
}
static void statClearCells(StatPage *p){
int i;
if( p->aCell ){
for(i=0; i<p->nCell; i++){
sqlite3_free(p->aCell[i].aOvfl);
}
sqlite3_free(p->aCell);
sqlite3_free(pCsr->aPage[i].aPg);
pCsr->aPage[i].aPg = 0;
}
sqlite3_reset(pCsr->pStmt);
pCsr->iPage = 0;
sqlite3_free(pCsr->zPath);
pCsr->zPath = 0;
pCsr->isEof = 0;
}
/* Resize the space-used counters inside of the cursor */
static void statResetCounts(StatCursor *pCsr){
pCsr->nCell = 0;
pCsr->nMxPayload = 0;
pCsr->nUnused = 0;
pCsr->nPayload = 0;
pCsr->szPage = 0;
pCsr->nPage = 0;
}
/*
** Close a DBSTAT cursor.
*/
static int statClose(sqlite3_vtab_cursor *pCursor){
StatCursor *pCsr = (StatCursor *)pCursor;
statResetCsr(pCsr);
sqlite3_finalize(pCsr->pStmt);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** For a single cell on a btree page, compute the number of bytes of
** content (payload) stored on that page. That is to say, compute the
p->flags = 0;
statClearCells(p);
return SQLITE_OK;
}
/*
** Populate the pCsr->iOffset and pCsr->szPage member variables. Based on
** the current value of pCsr->iPageno.
*/
static void statSizeAndOffset(StatCursor *pCsr){
StatTable *pTab = (StatTable *)((sqlite3_vtab_cursor *)pCsr)->pVtab;
Btree *pBt = pTab->db->aDb[pTab->iDb].pBt;
Pager *pPager = sqlite3BtreePager(pBt);
sqlite3_file *fd;
sqlite3_int64 x[2];
/* If connected to a ZIPVFS backend, find the page size and
** offset from ZIPVFS.
*/
fd = sqlite3PagerFile(pPager);
x[0] = pCsr->iPageno;
if( rc==SQLITE_OK ){
const u8 *a = sqlite3PagerGetData(pDbPage);
memcpy(pPg->aPg, a, pgsz);
sqlite3PagerUnref(pDbPage);
}
return rc;
}
/*
** Move a DBSTAT cursor to the next entry. Normally, the next
** entry will be the next page, but in aggregated mode (pCsr->isAgg!=0),
** the next entry is the next btree.
*/
static int statNext(sqlite3_vtab_cursor *pCursor){
int rc;
int nPayload;
char *z;
StatCursor *pCsr = (StatCursor *)pCursor;
StatTable *pTab = (StatTable *)pCursor->pVtab;
Btree *pBt = pTab->db->aDb[pCsr->iDb].pBt;
Pager *pPager = sqlite3BtreePager(pBt);
sqlite3_free(pCsr->zPath);
pCsr->zPath = 0;
/* If computing aggregate space usage by btree, continue with the
** next page. The loop will exit via the return at label-statNext-done
*/
if( pCsr->isAgg ) goto statNextRestart;
}
}
return rc;
}
static int statEof(sqlite3_vtab_cursor *pCursor){
StatCursor *pCsr = (StatCursor *)pCursor;
return pCsr->isEof;
}
/* Initialize a cursor according to the query plan idxNum using the
** arguments in argv[0]. See statBestIndex() for a description of the
** meaning of the bits in idxNum.
*/
static int statFilter(
sqlite3_vtab_cursor *pCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
StatCursor *pCsr = (StatCursor *)pCursor;
StatTable *pTab = (StatTable*)(pCursor->pVtab);
sqlite3_str *pSql; /* Query of btrees to analyze */
char *zSql; /* String value of pSql */
int iArg = 0; /* Count of argv[] parameters used so far */
int rc = SQLITE_OK; /* Result of this operation */
const char *zName = 0; /* Only provide analysis of this table */
}
if( rc==SQLITE_OK ){
pCsr->iPage = -1;
rc = statNext(pCursor);
}
return rc;
}
static int statColumn(
sqlite3_vtab_cursor *pCursor,
sqlite3_context *ctx,
int i
){
StatCursor *pCsr = (StatCursor *)pCursor;
switch( i ){
case 0: /* name */
sqlite3_result_text(ctx, pCsr->zName, -1, SQLITE_TRANSIENT);
break;
case 1: /* path */
if( !pCsr->isAgg ){
break;
}
default: { /* aggregate */
sqlite3_result_int(ctx, pCsr->isAgg);
break;
}
}
return SQLITE_OK;
}
static int statRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
StatCursor *pCsr = (StatCursor *)pCursor;
*pRowid = pCsr->iPageno;
return SQLITE_OK;
}
/*
** Invoke this routine to register the "dbstat" virtual table module
*/
SQLITE_PRIVATE int sqlite3DbstatRegister(sqlite3 *db){
static sqlite3_module dbstat_module = {
0, /* iVersion */
statConnect, /* xCreate */
statConnect, /* xConnect */
statBestIndex, /* xBestIndex */
statDisconnect, /* xDisconnect */
statDisconnect, /* xDestroy */
statOpen, /* xOpen - open a cursor */
statClose, /* xClose - close a cursor */
statFilter, /* xFilter - configure scan constraints */
statNext, /* xNext - advance a cursor */
statEof, /* xEof - check for end of scan */
statColumn, /* xColumn - read data */
statRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
*/
/* #include "sqliteInt.h" ** Requires access to internal data structures ** */
#if (defined(SQLITE_ENABLE_DBPAGE_VTAB) || defined(SQLITE_TEST)) \
&& !defined(SQLITE_OMIT_VIRTUALTABLE)
typedef struct DbpageTable DbpageTable;
typedef struct DbpageCursor DbpageCursor;
struct DbpageCursor {
sqlite3_vtab_cursor base; /* Base class. Must be first */
int pgno; /* Current page number */
int mxPgno; /* Last page to visit on this scan */
Pager *pPager; /* Pager being read/written */
DbPage *pPage1; /* Page 1 of the database */
int iDb; /* Index of database to analyze */
int szPage; /* Size of each page in bytes */
};
struct DbpageTable {
sqlite3_vtab base; /* Base class. Must be first */
if( pIdxInfo->nOrderBy>=1
&& pIdxInfo->aOrderBy[0].iColumn<=0
&& pIdxInfo->aOrderBy[0].desc==0
){
pIdxInfo->orderByConsumed = 1;
}
return SQLITE_OK;
}
/*
** Open a new dbpagevfs cursor.
*/
static int dbpageOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
DbpageCursor *pCsr;
pCsr = (DbpageCursor *)sqlite3_malloc64(sizeof(DbpageCursor));
if( pCsr==0 ){
return SQLITE_NOMEM_BKPT;
}else{
memset(pCsr, 0, sizeof(DbpageCursor));
pCsr->base.pVtab = pVTab;
pCsr->pgno = -1;
}
*ppCursor = (sqlite3_vtab_cursor *)pCsr;
return SQLITE_OK;
}
/*
** Close a dbpagevfs cursor.
*/
static int dbpageClose(sqlite3_vtab_cursor *pCursor){
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
if( pCsr->pPage1 ) sqlite3PagerUnrefPageOne(pCsr->pPage1);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** Move a dbpagevfs cursor to the next entry in the file.
*/
static int dbpageNext(sqlite3_vtab_cursor *pCursor){
int rc = SQLITE_OK;
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
pCsr->pgno++;
return rc;
}
static int dbpageEof(sqlite3_vtab_cursor *pCursor){
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
return pCsr->pgno > pCsr->mxPgno;
}
/*
** idxNum:
**
** 0 schema=main, full table scan
** 1 schema=main, pgno=?1
** 2 schema=?1, full table scan
** 3 schema=?1, pgno=?2
**
** idxStr is not used
*/
static int dbpageFilter(
sqlite3_vtab_cursor *pCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
DbpageTable *pTab = (DbpageTable *)pCursor->pVtab;
int rc;
sqlite3 *db = pTab->db;
Btree *pBt;
(void)idxStr;
}
}else{
assert( pCsr->pgno==1 );
}
if( pCsr->pPage1 ) sqlite3PagerUnrefPageOne(pCsr->pPage1);
rc = sqlite3PagerGet(pCsr->pPager, 1, &pCsr->pPage1, 0);
return rc;
}
static int dbpageColumn(
sqlite3_vtab_cursor *pCursor,
sqlite3_context *ctx,
int i
){
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
int rc = SQLITE_OK;
switch( i ){
case 0: { /* pgno */
sqlite3_result_int(ctx, pCsr->pgno);
break;
}
}
default: { /* schema */
sqlite3 *db = sqlite3_context_db_handle(ctx);
sqlite3_result_text(ctx, db->aDb[pCsr->iDb].zDbSName, -1, SQLITE_STATIC);
break;
}
}
return rc;
}
static int dbpageRowid(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
DbpageCursor *pCsr = (DbpageCursor *)pCursor;
*pRowid = pCsr->pgno;
return SQLITE_OK;
}
static int dbpageUpdate(
sqlite3_vtab *pVtab,
int argc,
sqlite3_value **argv,
sqlite_int64 *pRowid
** Invoke this routine to register the "dbpage" virtual table module
*/
SQLITE_PRIVATE int sqlite3DbpageRegister(sqlite3 *db){
static sqlite3_module dbpage_module = {
0, /* iVersion */
dbpageConnect, /* xCreate */
dbpageConnect, /* xConnect */
dbpageBestIndex, /* xBestIndex */
dbpageDisconnect, /* xDisconnect */
dbpageDisconnect, /* xDestroy */
dbpageOpen, /* xOpen - open a cursor */
dbpageClose, /* xClose - close a cursor */
dbpageFilter, /* xFilter - configure scan constraints */
dbpageNext, /* xNext - advance a cursor */
dbpageEof, /* xEof - check for end of scan */
dbpageColumn, /* xColumn - read data */
dbpageRowid, /* xRowid - read data */
dbpageUpdate, /* xUpdate */
dbpageBegin, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
** output record.
*/
static void sessionMergeRecord(
u8 **paOut,
int nCol,
u8 *aLeft,
u8 *aRight
){
u8 *a1 = aLeft; /* Cursor used to iterate through aLeft */
u8 *a2 = aRight; /* Cursor used to iterate through aRight */
u8 *aOut = *paOut; /* Output cursor */
int iCol; /* Used to iterate from 0 to nCol */
for(iCol=0; iCol<nCol; iCol++){
int n1 = sessionSerialLen(a1);
int n2 = sessionSerialLen(a2);
if( *a2 ){
memcpy(aOut, a2, n2);
aOut += n2;
}else{
memcpy(aOut, a1, n1);
if( q=='[' ) q = ']';
while( z[iIn] ){
if( z[iIn]==q ){
if( z[iIn+1]!=q ){
/* Character iIn was the close quote. */
iIn++;
break;
}else{
/* Character iIn and iIn+1 form an escaped quote character. Skip
** the input cursor past both and copy a single quote character
** to the output buffer. */
iIn += 2;
z[iOut++] = q;
}
}else{
z[iOut++] = z[iIn++];
}
}
z[iOut] = '\0';
** These are used if the FTS5_SEGITER_REVERSE flag is set.
**
** For each rowid on the page corresponding to the current term, the
** corresponding aRowidOffset[] entry is set to the byte offset of the
** start of the "position-list-size" field within the page.
**
** iTermIdx:
** Index of current term on iTermLeafPgno.
**
** apTombstone/nTombstone:
** These are used for contentless_delete=1 tables only. When the cursor
** is first allocated, the apTombstone[] array is allocated so that it
** is large enough for all tombstones hash pages associated with the
** segment. The pages themselves are loaded lazily from the database as
** they are required.
*/
struct Fts5SegIter {
Fts5StructureSegment *pSeg; /* Segment to iterate through */
int flags; /* Mask of configuration flags */
int iLeafPgno; /* Current leaf page number */
Fts5Data *pLeaf; /* Current leaf data */
#if defined(SQLITE_TEST) || defined(SQLITE_FTS5_DEBUG)
typedef struct Fts5StructVtab Fts5StructVtab;
struct Fts5StructVtab {
sqlite3_vtab base;
};
typedef struct Fts5StructVcsr Fts5StructVcsr;
struct Fts5StructVcsr {
sqlite3_vtab_cursor base;
Fts5Structure *pStruct;
int iLevel;
int iSeg;
int iRowid;
};
/*
** Create a new fts5_structure() table-valued function.
*/
static int fts5structConnectMethod(
/*
** This method is the destructor for bytecodevtab objects.
*/
static int fts5structDisconnectMethod(sqlite3_vtab *pVtab){
Fts5StructVtab *p = (Fts5StructVtab*)pVtab;
sqlite3_free(p);
return SQLITE_OK;
}
/*
** Constructor for a new bytecodevtab_cursor object.
*/
static int fts5structOpenMethod(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCsr){
int rc = SQLITE_OK;
Fts5StructVcsr *pNew = 0;
pNew = sqlite3Fts5MallocZero(&rc, sizeof(*pNew));
*ppCsr = (sqlite3_vtab_cursor*)pNew;
return SQLITE_OK;
}
/*
** Destructor for a bytecodevtab_cursor.
*/
static int fts5structCloseMethod(sqlite3_vtab_cursor *cur){
Fts5StructVcsr *pCsr = (Fts5StructVcsr*)cur;
fts5StructureRelease(pCsr->pStruct);
sqlite3_free(pCsr);
return SQLITE_OK;
}
/*
** Advance a bytecodevtab_cursor to its next row of output.
*/
static int fts5structNextMethod(sqlite3_vtab_cursor *cur){
Fts5StructVcsr *pCsr = (Fts5StructVcsr*)cur;
Fts5Structure *p = pCsr->pStruct;
assert( pCsr->pStruct );
pCsr->iSeg++;
pCsr->iRowid++;
while( pCsr->iLevel<p->nLevel && pCsr->iSeg>=p->aLevel[pCsr->iLevel].nSeg ){
pCsr->iLevel++;
pCsr->iSeg = 0;
}
if( pCsr->iLevel>=p->nLevel ){
fts5StructureRelease(pCsr->pStruct);
pCsr->pStruct = 0;
}
return SQLITE_OK;
}
/*
** Return TRUE if the cursor has been moved off of the last
** row of output.
*/
static int fts5structEofMethod(sqlite3_vtab_cursor *cur){
Fts5StructVcsr *pCsr = (Fts5StructVcsr*)cur;
return pCsr->pStruct==0;
}
static int fts5structRowidMethod(
sqlite3_vtab_cursor *cur,
sqlite_int64 *piRowid
){
Fts5StructVcsr *pCsr = (Fts5StructVcsr*)cur;
*piRowid = pCsr->iRowid;
return SQLITE_OK;
}
/*
** Return values of columns for the row at which the bytecodevtab_cursor
** is currently pointing.
*/
static int fts5structColumnMethod(
sqlite3_vtab_cursor *cur, /* The cursor */
sqlite3_context *ctx, /* First argument to sqlite3_result_...() */
int i /* Which column to return */
){
Fts5StructVcsr *pCsr = (Fts5StructVcsr*)cur;
Fts5Structure *p = pCsr->pStruct;
Fts5StructureSegment *pSeg = &p->aLevel[pCsr->iLevel].aSeg[pCsr->iSeg];
switch( i ){
case 0: /* level */
sqlite3_result_int(ctx, pCsr->iLevel);
sqlite3_result_int64(ctx, pSeg->nEntryTombstone);
break;
case 10: /* nentry */
sqlite3_result_int64(ctx, pSeg->nEntry);
break;
}
return SQLITE_OK;
}
/*
** Initialize a cursor.
**
** idxNum==0 means show all subprograms
** idxNum==1 means show only the main bytecode and omit subprograms.
*/
static int fts5structFilterMethod(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
Fts5StructVcsr *pCsr = (Fts5StructVcsr *)pVtabCursor;
int rc = SQLITE_OK;
const u8 *aBlob = 0;
int nBlob = 0;
assert( argc==1 );
};
/*
** A single object of this type is allocated when the FTS5 module is
** registered with a database handle. It is used to store pointers to
** all registered FTS5 extensions - tokenizers and auxiliary functions.
*/
struct Fts5Global {
fts5_api api; /* User visible part of object (see fts5.h) */
sqlite3 *db; /* Associated database connection */
i64 iNextId; /* Used to allocate unique cursor ids */
Fts5Auxiliary *pAux; /* First in list of all aux. functions */
Fts5TokenizerModule *pTok; /* First in list of all tokenizer modules */
Fts5TokenizerModule *pDfltTok; /* Default tokenizer module */
Fts5Cursor *pCsr; /* First in list of all open cursors */
};
/*
** Each auxiliary function registered with the FTS5 module is represented
** by an object of the following type. All such objects are stored as part
** of the Fts5Global.pAux list.
*/
struct Fts5Auxiliary {
Fts5Global *pGlobal; /* Global context for this function */
char *zFunc; /* Function name (nul-terminated) */
void *pUserData; /* User pointer passed to xCreate() */
fts5_tokenizer x; /* Tokenizer functions */
void (*xDestroy)(void*); /* Destructor function */
Fts5TokenizerModule *pNext; /* Next registered tokenizer module */
};
struct Fts5FullTable {
Fts5Table p; /* Public class members from fts5Int.h */
Fts5Storage *pStorage; /* Document store */
Fts5Global *pGlobal; /* Global (connection wide) data */
Fts5Cursor *pSortCsr; /* Sort data from this cursor */
int iSavepoint; /* Successful xSavepoint()+1 */
#ifdef SQLITE_DEBUG
struct Fts5TransactionState ts;
#endif
};
struct Fts5MatchPhrase {
Fts5Buffer *pPoslist; /* Pointer to current poslist */
int nTerm; /* Size of phrase in terms */
struct Fts5Sorter {
sqlite3_stmt *pStmt;
i64 iRowid; /* Current rowid */
const u8 *aPoslist; /* Position lists for current row */
int nIdx; /* Number of entries in aIdx[] */
int aIdx[1]; /* Offsets into aPoslist for current row */
};
/*
** Virtual-table cursor object.
**
** iSpecial:
** If this is a 'special' query (refer to function fts5SpecialMatch()),
** then this variable contains the result of the query.
**
** iFirstRowid, iLastRowid:
** These variables are only used for FTS5_PLAN_MATCH cursors. Assuming the
** cursor iterates in ascending order of rowids, iFirstRowid is the lower
** limit of rowids to return, and iLastRowid the upper. In other words, the
** WHERE clause in the user's query might have been:
**
** <tbl> MATCH <expr> AND rowid BETWEEN $iFirstRowid AND $iLastRowid
**
** If the cursor iterates in descending order of rowid, iFirstRowid
** is the upper limit (i.e. the "first" rowid visited) and iLastRowid
** the lower.
*/
struct Fts5Cursor {
sqlite3_vtab_cursor base; /* Base class used by SQLite core */
Fts5Cursor *pNext; /* Next cursor in Fts5Cursor.pCsr list */
int *aColumnSize; /* Values for xColumnSize() */
i64 iCsrId; /* Cursor id */
/* Zero from this point onwards on cursor reset */
int ePlan; /* FTS5_PLAN_XXX value */
int bDesc; /* True for "ORDER BY rowid DESC" queries */
i64 iFirstRowid; /* Return no rowids earlier than this */
i64 iLastRowid; /* Return no rowids later than this */
sqlite3_stmt *pStmt; /* Statement used to read %_content */
Fts5Expr *pExpr; /* Expression for MATCH queries */
Fts5Sorter *pSorter; /* Sorter for "ORDER BY rank" queries */
int csrflags; /* Mask of cursor flags (see below) */
i64 iSpecial; /* Result of special query */
/* "rank" function. Populated on demand from vtab.xColumn(). */
char *zRank; /* Custom rank function */
char *zRankArgs; /* Custom rank function args */
Fts5Auxiliary *pRank; /* Rank callback (or NULL) */
int nRankArg; /* Number of trailing arguments for rank() */
sqlite3_value **apRankArg; /* Array of trailing arguments */
sqlite3_stmt *pRankArgStmt; /* Origin of objects in apRankArg[] */
#define FTS5CSR_REQUIRE_INST 0x08
#define FTS5CSR_FREE_ZRANK 0x10
#define FTS5CSR_REQUIRE_RESEEK 0x20
#define FTS5CSR_REQUIRE_POSLIST 0x40
#define BitFlagAllTest(x,y) (((x) & (y))==(y))
#define BitFlagTest(x,y) (((x) & (y))!=0)
/*
** Macros to Set(), Clear() and Test() cursor flags.
*/
#define CsrFlagSet(pCsr, flag) ((pCsr)->csrflags |= (flag))
#define CsrFlagClear(pCsr, flag) ((pCsr)->csrflags &= ~(flag))
#define CsrFlagTest(pCsr, flag) ((pCsr)->csrflags & (flag))
struct Fts5Auxdata {
Fts5Auxiliary *pAux; /* Extension to which this belongs */
void *pPtr; /* Pointer value */
void(*xDelete)(void*); /* Destructor */
Fts5Auxdata *pNext; /* Next object in linked list */
sqlite3_vtab **ppVtab, /* OUT: New sqlite3_vtab object */
char **pzErr /* OUT: sqlite3_malloc'd error message */
){
return fts5InitVtab(1, db, pAux, argc, argv, ppVtab, pzErr);
}
/*
** The different query plans.
*/
#define FTS5_PLAN_MATCH 1 /* (<tbl> MATCH ?) */
#define FTS5_PLAN_SOURCE 2 /* A source cursor for SORTED_MATCH */
#define FTS5_PLAN_SPECIAL 3 /* An internal query */
#define FTS5_PLAN_SORTED_MATCH 4 /* (<tbl> MATCH ? ORDER BY rank) */
#define FTS5_PLAN_SCAN 5 /* No usable constraint */
#define FTS5_PLAN_ROWID 6 /* (rowid = ?) */
/*
** Set the SQLITE_INDEX_SCAN_UNIQUE flag in pIdxInfo->flags. Unless this
** extension is currently being used by a version of SQLite too old to
** support index-info flags. In that case this function is a no-op.
*/
Fts5Cursor *pCsr;
for(pCsr=pTab->pGlobal->pCsr; pCsr; pCsr=pCsr->pNext){
if( pCsr->base.pVtab==(sqlite3_vtab*)pTab ) return SQLITE_OK;
}
return sqlite3Fts5StorageReset(pTab->pStorage);
}
/*
** Implementation of xOpen method.
*/
static int fts5OpenMethod(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCsr){
Fts5FullTable *pTab = (Fts5FullTable*)pVTab;
Fts5Config *pConfig = pTab->p.pConfig;
Fts5Cursor *pCsr = 0; /* New cursor object */
sqlite3_int64 nByte; /* Bytes of space to allocate */
int rc; /* Return code */
rc = fts5NewTransaction(pTab);
if( rc==SQLITE_OK ){
nByte = sizeof(Fts5Cursor) + pConfig->nCol * sizeof(int);
pCsr = (Fts5Cursor*)sqlite3_malloc64(nByte);
if( pCsr ){
Fts5Global *pGlobal = pTab->pGlobal;
memset(pCsr, 0, (size_t)nByte);
pCsr->aColumnSize = (int*)&pCsr[1];
pCsr->pNext = pGlobal->pCsr;
pGlobal->pCsr = pCsr;
pCsr->iCsrId = ++pGlobal->iNextId;
}else{
rc = SQLITE_NOMEM;
}
}
*ppCsr = (sqlite3_vtab_cursor*)pCsr;
return rc;
}
static int fts5StmtType(Fts5Cursor *pCsr){
if( pCsr->ePlan==FTS5_PLAN_SCAN ){
return (pCsr->bDesc) ? FTS5_STMT_SCAN_DESC : FTS5_STMT_SCAN_ASC;
}
return FTS5_STMT_LOOKUP;
}
/*
** This function is called after the cursor passed as the only argument
** is moved to point at a different row. It clears all cached data
** specific to the previous row stored by the cursor object.
*/
static void fts5CsrNewrow(Fts5Cursor *pCsr){
CsrFlagSet(pCsr,
FTS5CSR_REQUIRE_CONTENT
| FTS5CSR_REQUIRE_DOCSIZE
| FTS5CSR_REQUIRE_INST
| FTS5CSR_REQUIRE_POSLIST
);
}
sqlite3_free(pCsr->zRank);
sqlite3_free(pCsr->zRankArgs);
}
sqlite3Fts5IndexCloseReader(pTab->p.pIndex);
memset(&pCsr->ePlan, 0, sizeof(Fts5Cursor) - ((u8*)&pCsr->ePlan - (u8*)pCsr));
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5CloseMethod(sqlite3_vtab_cursor *pCursor){
if( pCursor ){
Fts5FullTable *pTab = (Fts5FullTable*)(pCursor->pVtab);
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
Fts5Cursor **pp;
fts5FreeCursorComponents(pCsr);
/* Remove the cursor from the Fts5Global.pCsr list */
for(pp=&pTab->pGlobal->pCsr; (*pp)!=pCsr; pp=&(*pp)->pNext);
*pp = pCsr->pNext;
sqlite3_free(pCsr);
}
return SQLITE_OK;
}
static int fts5SorterNext(Fts5Cursor *pCsr){
Fts5Sorter *pSorter = pCsr->pSorter;
}
fts5CsrNewrow(pCsr);
}
return rc;
}
/*
** Set the FTS5CSR_REQUIRE_RESEEK flag on all FTS5_PLAN_MATCH cursors
** open on table pTab.
*/
static void fts5TripCursors(Fts5FullTable *pTab){
Fts5Cursor *pCsr;
for(pCsr=pTab->pGlobal->pCsr; pCsr; pCsr=pCsr->pNext){
if( pCsr->ePlan==FTS5_PLAN_MATCH
&& pCsr->base.pVtab==(sqlite3_vtab*)pTab
){
CsrFlagSet(pCsr, FTS5CSR_REQUIRE_RESEEK);
}
}
}
/*
** If the REQUIRE_RESEEK flag is set on the cursor passed as the first
** argument, close and reopen all Fts5IndexIter iterators that the cursor
** is using. Then attempt to move the cursor to a rowid equal to or laster
** (in the cursors sort order - ASC or DESC) than the current rowid.
**
** If the new rowid is not equal to the old, set output parameter *pbSkip
** to 1 before returning. Otherwise, leave it unchanged.
**
** Return SQLITE_OK if successful or if no reseek was required, or an
** error code if an error occurred.
*/
static int fts5CursorReseek(Fts5Cursor *pCsr, int *pbSkip){
int rc = SQLITE_OK;
assert( *pbSkip==0 );
if( sqlite3Fts5ExprEof(pCsr->pExpr) ){
CsrFlagSet(pCsr, FTS5CSR_EOF);
*pbSkip = 1;
}
}
return rc;
}
/*
** Advance the cursor to the next row in the table that matches the
** search criteria.
**
** Return SQLITE_OK if nothing goes wrong. SQLITE_OK is returned
** even if we reach end-of-file. The fts5EofMethod() will be called
** subsequently to determine whether or not an EOF was hit.
*/
static int fts5NextMethod(sqlite3_vtab_cursor *pCursor){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int rc;
assert( (pCsr->ePlan<3)==
(pCsr->ePlan==FTS5_PLAN_MATCH || pCsr->ePlan==FTS5_PLAN_SOURCE)
);
assert( !CsrFlagTest(pCsr, FTS5CSR_EOF) );
/* If this cursor uses FTS5_PLAN_MATCH and this is a tokendata=1 table,
** clear any token mappings accumulated at the fts5_index.c level. In
** other cases, specifically FTS5_PLAN_SOURCE and FTS5_PLAN_SORTED_MATCH,
** we need to retain the mappings for the entire query. */
if( pCsr->ePlan==FTS5_PLAN_MATCH
&& ((Fts5Table*)pCursor->pVtab)->pConfig->bTokendata
){
sqlite3Fts5ExprClearTokens(pCsr->pExpr);
}
if( pCsr->ePlan<3 ){
** the virtual table xFilter method documentation for additional
** information.
**
** There are three possible query strategies:
**
** 1. Full-text search using a MATCH operator.
** 2. A by-rowid lookup.
** 3. A full-table scan.
*/
static int fts5FilterMethod(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, /* Strategy index */
const char *idxStr, /* Unused */
int nVal, /* Number of elements in apVal */
sqlite3_value **apVal /* Arguments for the indexing scheme */
){
Fts5FullTable *pTab = (Fts5FullTable*)(pCursor->pVtab);
Fts5Config *pConfig = pTab->p.pConfig;
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int rc = SQLITE_OK; /* Error code */
int bDesc; /* True if ORDER BY [rank|rowid] DESC */
pRowidLe = apVal[i];
break;
default: assert( idxStr[iIdxStr-1]=='>' );
pRowidGe = apVal[i];
break;
}
}
bOrderByRank = ((idxNum & FTS5_BI_ORDER_RANK) ? 1 : 0);
pCsr->bDesc = bDesc = ((idxNum & FTS5_BI_ORDER_DESC) ? 1 : 0);
/* Set the cursor upper and lower rowid limits. Only some strategies
** actually use them. This is ok, as the xBestIndex() method leaves the
** sqlite3_index_constraint.omit flag clear for range constraints
** on the rowid field. */
if( pRowidEq ){
pRowidLe = pRowidGe = pRowidEq;
}
if( bDesc ){
pCsr->iFirstRowid = fts5GetRowidLimit(pRowidLe, LARGEST_INT64);
pCsr->iLastRowid = fts5GetRowidLimit(pRowidGe, SMALLEST_INT64);
}else{
pCsr->iLastRowid = fts5GetRowidLimit(pRowidLe, LARGEST_INT64);
pCsr->iFirstRowid = fts5GetRowidLimit(pRowidGe, SMALLEST_INT64);
}
rc = sqlite3Fts5IndexLoadConfig(pTab->p.pIndex);
if( rc!=SQLITE_OK ) goto filter_out;
if( pTab->pSortCsr ){
/* If pSortCsr is non-NULL, then this call is being made as part of
** processing for a "... MATCH <expr> ORDER BY rank" query (ePlan is
** set to FTS5_PLAN_SORTED_MATCH). pSortCsr is the cursor that will
** return results to the user for this query. The current cursor
** (pCursor) is used to execute the query issued by function
** fts5CursorFirstSorted() above. */
assert( pRowidEq==0 && pRowidLe==0 && pRowidGe==0 && pRank==0 );
assert( nVal==0 && bOrderByRank==0 && bDesc==0 );
assert( pCsr->iLastRowid==LARGEST_INT64 );
assert( pCsr->iFirstRowid==SMALLEST_INT64 );
if( pTab->pSortCsr->bDesc ){
pCsr->iLastRowid = pTab->pSortCsr->iFirstRowid;
pCsr->iFirstRowid = pTab->pSortCsr->iLastRowid;
}else{
filter_out:
sqlite3Fts5ExprFree(pExpr);
pConfig->pzErrmsg = pzErrmsg;
return rc;
}
/*
** This is the xEof method of the virtual table. SQLite calls this
** routine to find out if it has reached the end of a result set.
*/
static int fts5EofMethod(sqlite3_vtab_cursor *pCursor){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
return (CsrFlagTest(pCsr, FTS5CSR_EOF) ? 1 : 0);
}
/*
** Return the rowid that the cursor currently points to.
*/
static i64 fts5CursorRowid(Fts5Cursor *pCsr){
assert( pCsr->ePlan==FTS5_PLAN_MATCH
|| pCsr->ePlan==FTS5_PLAN_SORTED_MATCH
|| pCsr->ePlan==FTS5_PLAN_SOURCE
);
if( pCsr->pSorter ){
return pCsr->pSorter->iRowid;
}else{
return sqlite3Fts5ExprRowid(pCsr->pExpr);
}
}
/*
** This is the xRowid method. The SQLite core calls this routine to
** retrieve the rowid for the current row of the result set. fts5
** exposes %_content.rowid as the rowid for the virtual table. The
** rowid should be written to *pRowid.
*/
static int fts5RowidMethod(sqlite3_vtab_cursor *pCursor, sqlite_int64 *pRowid){
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int ePlan = pCsr->ePlan;
assert( CsrFlagTest(pCsr, FTS5CSR_EOF)==0 );
switch( ePlan ){
case FTS5_PLAN_SPECIAL:
*pRowid = 0;
break;
case FTS5_PLAN_SOURCE:
default:
*pRowid = sqlite3_column_int64(pCsr->pStmt, 0);
break;
}
return SQLITE_OK;
}
/*
** If the cursor requires seeking (bSeekRequired flag is set), seek it.
** Return SQLITE_OK if no error occurs, or an SQLite error code otherwise.
**
** If argument bErrormsg is true and an error occurs, an error message may
** be left in sqlite3_vtab.zErrMsg.
*/
static int fts5SeekCursor(Fts5Cursor *pCsr, int bErrormsg){
int rc = SQLITE_OK;
/* If the cursor does not yet have a statement handle, obtain one now. */
if( pCsr->pStmt==0 ){
Fts5FullTable *pTab = (Fts5FullTable*)(pCsr->base.pVtab);
int eStmt = fts5StmtType(pCsr);
rc = sqlite3Fts5StorageStmt(
pTab->pStorage, eStmt, &pCsr->pStmt, (bErrormsg?&pTab->p.base.zErrMsg:0)
);
assert( rc!=SQLITE_OK || pTab->p.base.zErrMsg==0 );
assert( CsrFlagTest(pCsr, FTS5CSR_REQUIRE_CONTENT) );
}
|| sqlite3_value_type(apVal[0])==SQLITE_NULL
);
assert( pTab->p.pConfig->pzErrmsg==0 );
if( pConfig->pgsz==0 ){
rc = sqlite3Fts5IndexLoadConfig(pTab->p.pIndex);
if( rc!=SQLITE_OK ) return rc;
}
pTab->p.pConfig->pzErrmsg = &pTab->p.base.zErrMsg;
/* Put any active cursors into REQUIRE_SEEK state. */
fts5TripCursors(pTab);
eType0 = sqlite3_value_type(apVal[0]);
if( eType0==SQLITE_NULL
&& sqlite3_value_type(apVal[2+pConfig->nCol])!=SQLITE_NULL
){
/* A "special" INSERT op. These are handled separately. */
const char *z = (const char*)sqlite3_value_text(apVal[2+pConfig->nCol]);
if( pConfig->eContent!=FTS5_CONTENT_NORMAL
&& 0==sqlite3_stricmp("delete", z)
** Implementation of the xSetAuxdata() method.
*/
static int fts5ApiSetAuxdata(
Fts5Context *pCtx, /* Fts5 context */
void *pPtr, /* Pointer to save as auxdata */
void(*xDelete)(void*) /* Destructor for pPtr (or NULL) */
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5Auxdata *pData;
/* Search through the cursors list of Fts5Auxdata objects for one that
** corresponds to the currently executing auxiliary function. */
for(pData=pCsr->pAuxdata; pData; pData=pData->pNext){
if( pData->pAux==pCsr->pAux ) break;
}
if( pData ){
if( pData->xDelete ){
pData->xDelete(pData->pPtr);
}
}else{
Fts5Context *pCtx,
int iPhrase,
void *pUserData,
int(*xCallback)(const Fts5ExtensionApi*, Fts5Context*, void*)
){
Fts5Cursor *pCsr = (Fts5Cursor*)pCtx;
Fts5FullTable *pTab = (Fts5FullTable*)(pCsr->base.pVtab);
int rc;
Fts5Cursor *pNew = 0;
rc = fts5OpenMethod(pCsr->base.pVtab, (sqlite3_vtab_cursor**)&pNew);
if( rc==SQLITE_OK ){
pNew->ePlan = FTS5_PLAN_MATCH;
pNew->iFirstRowid = SMALLEST_INT64;
pNew->iLastRowid = LARGEST_INT64;
pNew->base.pVtab = (sqlite3_vtab*)pTab;
rc = sqlite3Fts5ExprClonePhrase(pCsr->pExpr, iPhrase, &pNew->pExpr);
}
if( rc==SQLITE_OK ){
for(rc = fts5CursorFirst(pTab, pNew, 0);
rc==SQLITE_OK && CsrFlagTest(pNew, FTS5CSR_EOF)==0;
rc = fts5NextMethod((sqlite3_vtab_cursor*)pNew)
){
rc = xCallback(&sFts5Api, (Fts5Context*)pNew, pUserData);
if( rc!=SQLITE_OK ){
if( rc==SQLITE_DONE ) rc = SQLITE_OK;
break;
}
}
}
fts5CloseMethod((sqlite3_vtab_cursor*)pNew);
return rc;
}
static void fts5ApiInvoke(
Fts5Auxiliary *pAux,
Fts5Cursor *pCsr,
sqlite3_context *context,
int argc,
sqlite3_value **argv
){
Fts5Auxiliary *pAux;
Fts5Cursor *pCsr;
i64 iCsrId;
assert( argc>=1 );
pAux = (Fts5Auxiliary*)sqlite3_user_data(context);
iCsrId = sqlite3_value_int64(argv[0]);
pCsr = fts5CursorFromCsrid(pAux->pGlobal, iCsrId);
if( pCsr==0 || pCsr->ePlan==0 ){
char *zErr = sqlite3_mprintf("no such cursor: %lld", iCsrId);
sqlite3_result_error(context, zErr, -1);
sqlite3_free(zErr);
}else{
fts5ApiInvoke(pAux, pCsr, context, argc-1, &argv[1]);
}
}
/*
** Given cursor id iId, return a pointer to the corresponding Fts5Table
** object. Or NULL If the cursor id does not exist.
*/
static Fts5Table *sqlite3Fts5TableFromCsrid(
Fts5Global *pGlobal, /* FTS5 global context for db handle */
i64 iCsrId /* Id of cursor to find */
){
Fts5Cursor *pCsr;
pCsr = fts5CursorFromCsrid(pGlobal, iCsrId);
if( pCsr ){
return (Fts5Table*)pCsr->base.pVtab;
}
return 0;
}
/*
** Return a "position-list blob" corresponding to the current position of
** cursor pCsr via sqlite3_result_blob(). A position-list blob contains
** the current position-list for each phrase in the query associated with
** cursor pCsr.
**
** A position-list blob begins with (nPhrase-1) varints, where nPhrase is
** the number of phrases in the query. Following the varints are the
** concatenated position lists for each phrase, in order.
**
** The first varint (if it exists) contains the size of the position list
** for phrase 0. The second (same disclaimer) contains the size of position
** list 1. And so on. There is no size field for the final position list,
** as it can be derived from the total size of the blob.
*/
default:
break;
}
sqlite3_result_blob(pCtx, val.p, val.n, sqlite3_free);
return rc;
}
/*
** This is the xColumn method, called by SQLite to request a value from
** the row that the supplied cursor currently points to.
*/
static int fts5ColumnMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
int iCol /* Index of column to read value from */
){
Fts5FullTable *pTab = (Fts5FullTable*)(pCursor->pVtab);
Fts5Config *pConfig = pTab->p.pConfig;
Fts5Cursor *pCsr = (Fts5Cursor*)pCursor;
int rc = SQLITE_OK;
assert( CsrFlagTest(pCsr, FTS5CSR_EOF)==0 );
if( pCsr->ePlan==FTS5_PLAN_SPECIAL ){
if( iCol==pConfig->nCol ){
sqlite3_result_int64(pCtx, pCsr->iSpecial);
}
}else
if( iCol==pConfig->nCol ){
/* User is requesting the value of the special column with the same name
** as the table. Return the cursor integer id number. This value is only
** useful in that it may be passed as the first argument to an FTS5
** auxiliary function. */
sqlite3_result_int64(pCtx, pCsr->iCsrId);
}else if( iCol==pConfig->nCol+1 ){
/* The value of the "rank" column. */
if( pCsr->ePlan==FTS5_PLAN_SOURCE ){
fts5PoslistBlob(pCtx, pCsr);
}else if(
pCsr->ePlan==FTS5_PLAN_MATCH
sqlite3_vtab base;
char *zFts5Tbl; /* Name of fts5 table */
char *zFts5Db; /* Db containing fts5 table */
sqlite3 *db; /* Database handle */
Fts5Global *pGlobal; /* FTS5 global object for this database */
int eType; /* FTS5_VOCAB_COL, ROW or INSTANCE */
unsigned bBusy; /* True if busy */
};
struct Fts5VocabCursor {
sqlite3_vtab_cursor base;
sqlite3_stmt *pStmt; /* Statement holding lock on pIndex */
Fts5Table *pFts5; /* Associated FTS5 table */
int bEof; /* True if this cursor is at EOF */
Fts5IndexIter *pIter; /* Term/rowid iterator object */
void *pStruct; /* From sqlite3Fts5StructureRef() */
int nLeTerm; /* Size of zLeTerm in bytes */
char *zLeTerm; /* (term <= $zLeTerm) paramater, or NULL */
/* These are used by 'col' tables only */
int iCol;
i64 *aCnt;
i64 *aDoc;
pInfo->idxNum = idxNum;
return SQLITE_OK;
}
/*
** Implementation of xOpen method.
*/
static int fts5VocabOpenMethod(
sqlite3_vtab *pVTab,
sqlite3_vtab_cursor **ppCsr
){
Fts5VocabTable *pTab = (Fts5VocabTable*)pVTab;
Fts5Table *pFts5 = 0;
Fts5VocabCursor *pCsr = 0;
int rc = SQLITE_OK;
sqlite3_stmt *pStmt = 0;
char *zSql = 0;
if( pTab->bBusy ){
pVTab->zErrMsg = sqlite3_mprintf(
if( pCsr ){
pCsr->pFts5 = pFts5;
pCsr->pStmt = pStmt;
pCsr->aCnt = (i64*)&pCsr[1];
pCsr->aDoc = &pCsr->aCnt[pFts5->pConfig->nCol];
}else{
sqlite3_finalize(pStmt);
}
*ppCsr = (sqlite3_vtab_cursor*)pCsr;
return rc;
}
static void fts5VocabResetCursor(Fts5VocabCursor *pCsr){
pCsr->rowid = 0;
sqlite3Fts5IterClose(pCsr->pIter);
sqlite3Fts5StructureRelease(pCsr->pStruct);
pCsr->pStruct = 0;
pCsr->pIter = 0;
sqlite3_free(pCsr->zLeTerm);
pCsr->nLeTerm = -1;
pCsr->zLeTerm = 0;
pCsr->bEof = 0;
}
/*
** Close the cursor. For additional information see the documentation
** on the xClose method of the virtual table interface.
*/
static int fts5VocabCloseMethod(sqlite3_vtab_cursor *pCursor){
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
fts5VocabResetCursor(pCsr);
sqlite3Fts5BufferFree(&pCsr->term);
sqlite3_finalize(pCsr->pStmt);
sqlite3_free(pCsr);
return SQLITE_OK;
}
static int fts5VocabInstanceNewTerm(Fts5VocabCursor *pCsr){
int rc = SQLITE_OK;
if( rc ){
pCsr->bEof = 1;
break;
}
}
return rc;
}
/*
** Advance the cursor to the next row in the table.
*/
static int fts5VocabNextMethod(sqlite3_vtab_cursor *pCursor){
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
Fts5VocabTable *pTab = (Fts5VocabTable*)pCursor->pVtab;
int nCol = pCsr->pFts5->pConfig->nCol;
int rc;
rc = sqlite3Fts5StructureTest(pCsr->pFts5->pIndex, pCsr->pStruct);
if( rc!=SQLITE_OK ) return rc;
pCsr->rowid++;
if( pTab->eType==FTS5_VOCAB_INSTANCE ){
rc = FTS5_CORRUPT;
}
}
return rc;
}
/*
** This is the xFilter implementation for the virtual table.
*/
static int fts5VocabFilterMethod(
sqlite3_vtab_cursor *pCursor, /* The cursor used for this query */
int idxNum, /* Strategy index */
const char *zUnused, /* Unused */
int nUnused, /* Number of elements in apVal */
sqlite3_value **apVal /* Arguments for the indexing scheme */
){
Fts5VocabTable *pTab = (Fts5VocabTable*)pCursor->pVtab;
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
int eType = pTab->eType;
int rc = SQLITE_OK;
rc = fts5VocabNextMethod(pCursor);
}
return rc;
}
/*
** This is the xEof method of the virtual table. SQLite calls this
** routine to find out if it has reached the end of a result set.
*/
static int fts5VocabEofMethod(sqlite3_vtab_cursor *pCursor){
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
return pCsr->bEof;
}
static int fts5VocabColumnMethod(
sqlite3_vtab_cursor *pCursor, /* Cursor to retrieve value from */
sqlite3_context *pCtx, /* Context for sqlite3_result_xxx() calls */
int iCol /* Index of column to read value from */
){
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
int eDetail = pCsr->pFts5->pConfig->eDetail;
int eType = ((Fts5VocabTable*)(pCursor->pVtab))->eType;
i64 iVal = 0;
if( iCol==0 ){
sqlite3_result_text(
if( iVal>0 ) sqlite3_result_int64(pCtx, iVal);
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. The
** rowid should be written to *pRowid.
*/
static int fts5VocabRowidMethod(
sqlite3_vtab_cursor *pCursor,
sqlite_int64 *pRowid
){
Fts5VocabCursor *pCsr = (Fts5VocabCursor*)pCursor;
*pRowid = pCsr->rowid;
return SQLITE_OK;
}
static int sqlite3Fts5VocabInit(Fts5Global *pGlobal, sqlite3 *db){
static const sqlite3_module fts5Vocab = {
/* iVersion */ 2,
/* stmt_vtab is a subclass of sqlite3_vtab which will
** serve as the underlying representation of a stmt virtual table
*/
typedef struct stmt_vtab stmt_vtab;
struct stmt_vtab {
sqlite3_vtab base; /* Base class - must be first */
sqlite3 *db; /* Database connection for this stmt vtab */
};
/* stmt_cursor is a subclass of sqlite3_vtab_cursor which will
** serve as the underlying representation of a cursor that scans
** over rows of the result
*/
typedef struct stmt_cursor stmt_cursor;
struct stmt_cursor {
sqlite3_vtab_cursor base; /* Base class - must be first */
sqlite3 *db; /* Database connection for this cursor */
StmtRow *pRow; /* Current row */
};
/*
** The stmtConnect() method is invoked to create a new
** stmt_vtab that describes the stmt virtual table.
**
** Think of this routine as the constructor for stmt_vtab objects.
**
** All this routine needs to do is:
pNew = sqlite3_malloc64( sizeof(*pNew) );
*ppVtab = (sqlite3_vtab*)pNew;
if( pNew==0 ) return SQLITE_NOMEM;
memset(pNew, 0, sizeof(*pNew));
pNew->db = db;
}
return rc;
}
/*
** This method is the destructor for stmt_cursor objects.
*/
static int stmtDisconnect(sqlite3_vtab *pVtab){
sqlite3_free(pVtab);
return SQLITE_OK;
}
/*
** Constructor for a new stmt_cursor object.
*/
static int stmtOpen(sqlite3_vtab *p, sqlite3_vtab_cursor **ppCursor){
stmt_cursor *pCur;
pCur = sqlite3_malloc64( sizeof(*pCur) );
if( pCur==0 ) return SQLITE_NOMEM;
memset(pCur, 0, sizeof(*pCur));
pCur->db = ((stmt_vtab*)p)->db;
*ppCursor = &pCur->base;
return SQLITE_OK;
}
static void stmtCsrReset(stmt_cursor *pCur){
StmtRow *pRow = 0;
StmtRow *pNext = 0;
for(pRow=pCur->pRow; pRow; pRow=pNext){
pNext = pRow->pNext;
sqlite3_free(pRow);
}
pCur->pRow = 0;
}
/*
** Destructor for a stmt_cursor.
*/
static int stmtClose(sqlite3_vtab_cursor *cur){
stmtCsrReset((stmt_cursor*)cur);
sqlite3_free(cur);
return SQLITE_OK;
}
/*
** Advance a stmt_cursor to its next row of output.
*/
static int stmtNext(sqlite3_vtab_cursor *cur){
stmt_cursor *pCur = (stmt_cursor*)cur;
StmtRow *pNext = pCur->pRow->pNext;
sqlite3_free(pCur->pRow);
pCur->pRow = pNext;
return SQLITE_OK;
}
/*
** Return values of columns for the row at which the stmt_cursor
** is currently pointing.
*/
static int stmtColumn(
sqlite3_vtab_cursor *cur, /* The cursor */
sqlite3_context *ctx, /* First argument to sqlite3_result_...() */
int i /* Which column to return */
){
stmt_cursor *pCur = (stmt_cursor*)cur;
StmtRow *pRow = pCur->pRow;
if( i==STMT_COLUMN_SQL ){
sqlite3_result_text(ctx, pRow->zSql, -1, SQLITE_TRANSIENT);
}else{
sqlite3_result_int(ctx, pRow->aCol[i]);
}
return SQLITE_OK;
}
/*
** Return the rowid for the current row. In this implementation, the
** rowid is the same as the output value.
*/
static int stmtRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
stmt_cursor *pCur = (stmt_cursor*)cur;
*pRowid = pCur->pRow->iRowid;
return SQLITE_OK;
}
/*
** Return TRUE if the cursor has been moved off of the last
** row of output.
*/
static int stmtEof(sqlite3_vtab_cursor *cur){
stmt_cursor *pCur = (stmt_cursor*)cur;
return pCur->pRow==0;
}
/*
** This method is called to "rewind" the stmt_cursor object back
** to the first row of output. This method is always called at least
** once prior to any call to stmtColumn() or stmtRowid() or
** stmtEof().
*/
static int stmtFilter(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
stmt_cursor *pCur = (stmt_cursor *)pVtabCursor;
sqlite3_stmt *p = 0;
sqlite3_int64 iRowid = 1;
StmtRow **ppRow = 0;
(void)idxNum;
(void)idxStr;
(void)argc;
(void)argv;
stmtCsrReset(pCur);
ppRow = &pCur->pRow;
** This following structure defines all the methods for the
** stmt virtual table.
*/
static sqlite3_module stmtModule = {
0, /* iVersion */
0, /* xCreate */
stmtConnect, /* xConnect */
stmtBestIndex, /* xBestIndex */
stmtDisconnect, /* xDisconnect */
0, /* xDestroy */
stmtOpen, /* xOpen - open a cursor */
stmtClose, /* xClose - close a cursor */
stmtFilter, /* xFilter - configure scan constraints */
stmtNext, /* xNext - advance a cursor */
stmtEof, /* xEof - check for end of scan */
stmtColumn, /* xColumn - read data */
stmtRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
** ^This interface disables all automatic extensions previously
** registered using [sqlite3_auto_extension()].
*/
SQLITE_API void sqlite3_reset_auto_extension(void);
/*
** 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
** KEYWORDS: sqlite3_module {virtual table module}
**
** This structure, sometimes called a "virtual table module",
** defines the implementation of a [virtual table].
** This structure consists mostly of methods for the 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);
/* The methods above are in version 1 of the sqlite_module object. Those
**
** ^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.
*/
struct sqlite3_vtab {
const sqlite3_module *pModule; /* The module for this virtual table */
int nRef; /* Number of open cursors */
char *zErrMsg; /* Error message from sqlite3_mprintf() */
/* Virtual table implementations will typically add additional fields */
};
/*
** CAPI3REF: Virtual Table Cursor Object
** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}
**
** Every [virtual table 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
** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed
** by the [sqlite3_module.xClose | xClose] method. Cursors are used
** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods
** 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.
*/
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
**
** ^The [xCreate] and [xConnect] methods of a
** [virtual table module] call this interface
** to declare the format (the names and datatypes of the columns) of
** the virtual tables they implement.
*/
SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*);
/*
** CAPI3REF: Flush caches to disk mid-transaction
** METHOD: sqlite3
**
** ^If a write-transaction is open on [database connection] D when the
** [sqlite3_db_cacheflush(D)] interface invoked, any dirty
** pages in the pager-cache that are not currently in use are written out
** to disk. A dirty page may be in use if a database cursor created by an
** active SQL statement is reading from it, or if it is page 1 of a database
** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]
** interface flushes caches for all schemas - "main", "temp", and
** any [attached] databases.
**
** ^If this function needs to obtain extra database locks before dirty pages
** can be flushed to disk, it does so. ^If those locks cannot be obtained
** immediately and there is a busy-handler callback configured, it is invoked
** in the usual manner. ^If the required lock still cannot be obtained, then
** the database is skipped and an attempt made to flush any dirty pages
** CAPI3REF: Session Object Handle
**
** An instance of this object is a [session] that can be used to
** record changes to a database.
*/
typedef struct sqlite3_session sqlite3_session;
/*
** CAPI3REF: Changeset Iterator Handle
**
** An instance of this object acts as a cursor for iterating
** over the elements of a [changeset] or [patchset].
*/
typedef struct sqlite3_changeset_iter sqlite3_changeset_iter;
/*
** CAPI3REF: Create A New Session Object
** CONSTRUCTOR: sqlite3_session
**
** Create a new session object attached to database handle db. If successful,
** a pointer to the new object is written to *ppSession and SQLITE_OK is
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