/*
** Generate code that will assemble an index key and put it in register
** regOut. The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key. The
** block of registers has already been deallocated by the time
** this routine returns.
*/
int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iCur, /* Cursor number for the pIdx->pTable table */
int regOut, /* Write the new index key to this register */
int doMakeRec /* Run the OP_MakeRecord instruction if true */
){
Vdbe *v = pParse->pVdbe;
int j;
Table *pTab = pIdx->pTable;
int regBase;
int nCol;
nCol = pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol+1);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
for(j=0; j<nCol; j++){
int idx = pIdx->aiColumn[j];
if( idx==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
}else{
sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
sqlite3ColumnDefault(v, pTab, idx, -1);
}
}
if( doMakeRec ){
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v, pIdx), 0);
}
sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
return regBase;
}
/*
** 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.
*/
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;
SrcList *pSrc; /* FROM clause for the UPDATE */
int iDataCur;
assert( v!=0 );
assert( pUpsert!=0 );
VdbeNoopComment((v, "Begin DO UPDATE of UPSERT"));
iDataCur = pUpsert->iDataCur;
if( pIdx && iCur!=iDataCur ){
if( HasRowid(pTab) ){
int regRowid = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_IdxRowid, iCur, regRowid);
sqlite3VdbeAddOp3(v, OP_SeekRowid, iDataCur, 0, regRowid);
VdbeCoverage(v);
sqlite3ReleaseTempReg(pParse, regRowid);
}else{
Index *pPk = sqlite3PrimaryKeyIndex(pTab);
int nPk = pPk->nKeyCol;
int iPk = pParse->nMem+1;
int i;
pParse->nMem += nPk;
for(i=0; i<nPk; i++){
int k;
assert( pPk->aiColumn[i]>=0 );
k = sqlite3ColumnOfIndex(pIdx, pPk->aiColumn[i]);
sqlite3VdbeAddOp3(v, OP_Column, iCur, k, iPk+i);
VdbeComment((v, "%s.%s", pIdx->zName,
pTab->aCol[pPk->aiColumn[i]].zName));
}
sqlite3VdbeVerifyAbortable(v, OE_Abort);
i = sqlite3VdbeAddOp4Int(v, OP_Found, iDataCur, 0, iPk, nPk);
VdbeCoverage(v);
sqlite3VdbeAddOp4(v, OP_Halt, SQLITE_CORRUPT, OE_Abort, 0,
"corrupt database", P4_STATIC);
sqlite3VdbeJumpHere(v, i);
}
}
/* pUpsert does not own pUpsertSrc - the outer INSERT statement does. So
** we have to make a copy before passing it down into sqlite3Update() */
pSrc = sqlite3SrcListDup(db, pUpsert->pUpsertSrc, 0);
sqlite3Update(pParse, pSrc, pUpsert->pUpsertSet,
pUpsert->pUpsertWhere, OE_Abort, 0, 0, pUpsert);
pUpsert->pUpsertSet = 0; /* Will have been deleted by sqlite3Update() */
pUpsert->pUpsertWhere = 0; /* Will have been deleted by sqlite3Update() */
VdbeNoopComment((v, "End DO UPDATE of UPSERT"));
}
/*
** 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.
** A partial index should be skipped if its WHERE clause evaluates
** to false or null. If pIdx is not a partial index, *piPartIdxLabel
** will be set to zero which is an empty label that is ignored by
** sqlite3VdbeResolveLabel().
*/
int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iDataCur, /* Cursor number from which to take column data */
int regOut, /* Put the new key into this register if not 0 */
int prefixOnly, /* Compute only a unique prefix of the key */
int *piPartIdxLabel /* OUT: Jump to this label to skip partial index */
){
Vdbe *v = pParse->pVdbe;
int j;
Table *pTab = pIdx->pTable;
int regBase;
int nCol;
Index *pPk;
if( piPartIdxLabel ){
if( pIdx->pPartIdxWhere ){
*piPartIdxLabel = sqlite3VdbeMakeLabel(v);
pParse->iPartIdxTab = iDataCur;
sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel,
SQLITE_JUMPIFNULL);
}else{
*piPartIdxLabel = 0;
}
}
nCol = (prefixOnly && pIdx->uniqNotNull) ? pIdx->nKeyCol : pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol);
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
for(j=0; j<nCol; j++){
i16 idx = pIdx->aiColumn[j];
if( pPk ) idx = sqlite3ColumnOfIndex(pPk, idx);
if( idx<0 || idx==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Rowid, iDataCur, regBase+j);
}else{
sqlite3VdbeAddOp3(v, OP_Column, iDataCur, idx, regBase+j);
sqlite3ColumnDefault(v, pTab, pIdx->aiColumn[j], -1);
}
}
if( regOut ){
const char *zAff;
if( pTab->pSelect
|| OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)
){
zAff = 0;
}else{
zAff = sqlite3IndexAffinityStr(v, pIdx);
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regOut);
sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);
}
sqlite3ReleaseTempRange(pParse, regBase, nCol);
return regBase;
}
/*
** Generate code that will assemble an index key and put it in register
** regOut. The key with be for index pIdx which is an index on pTab.
** iCur is the index of a cursor open on the pTab table and pointing to
** the entry that needs indexing.
**
** Return a register number which is the first in a block of
** registers that holds the elements of the index key. The
** block of registers has already been deallocated by the time
** this routine returns.
**
** 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.
** A partial index should be skipped if its WHERE clause evaluates
** to false or null. If pIdx is not a partial index, *piPartIdxLabel
** will be set to zero which is an empty label that is ignored by
** sqlite3VdbeResolveLabel().
*/
int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iCur, /* Cursor number for the pIdx->pTable table */
int regOut, /* Write the new index key to this register */
int doMakeRec, /* Run the OP_MakeRecord instruction if true */
int *piPartIdxLabel /* OUT: Jump to this label to skip partial index */
){
Vdbe *v = pParse->pVdbe;
int j;
Table *pTab = pIdx->pTable;
int regBase;
int nCol;
if( piPartIdxLabel ){
if( pIdx->pPartIdxWhere ){
*piPartIdxLabel = sqlite3VdbeMakeLabel(v);
pParse->iPartIdxTab = iCur;
sqlite3ExprIfFalse(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel,
SQLITE_JUMPIFNULL);
}else{
*piPartIdxLabel = 0;
}
}
nCol = pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol+1);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regBase+nCol);
for(j=0; j<nCol; j++){
int idx = pIdx->aiColumn[j];
if( idx==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_SCopy, regBase+nCol, regBase+j);
}else{
sqlite3VdbeAddOp3(v, OP_Column, iCur, idx, regBase+j);
sqlite3ColumnDefault(v, pTab, idx, -1);
}
}
if( doMakeRec ){
const char *zAff;
if( pTab->pSelect
|| OptimizationDisabled(pParse->db, SQLITE_IdxRealAsInt)
){
zAff = 0;
}else{
zAff = sqlite3IndexAffinityStr(v, pIdx);
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol+1, regOut);
sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);
}
sqlite3ReleaseTempRange(pParse, regBase, nCol+1);
return regBase;
}
/*
** Generate code for the trigger program associated with trigger p on
** table pTab. The reg, orconf and ignoreJump parameters passed to this
** function are the same as those described in the header function for
** sqlite3CodeRowTrigger()
*/
SQLITE_PRIVATE void sqlite3CodeRowTriggerDirect(
Parse *pParse, /* Parse context */
Trigger *p, /* Trigger to code */
Table *pTab, /* The table to code triggers from */
int reg, /* Reg array containing OLD.* and NEW.* values */
int orconf, /* ON CONFLICT policy */
int ignoreJump /* Instruction to jump to for RAISE(IGNORE) */
){
Vdbe *v = sqlite3GetVdbe(pParse); /* Main VM */
TriggerPrg *pPrg;
pPrg = getRowTrigger(pParse, p, pTab, orconf);
assert( pPrg || pParse->nErr || pParse->db->mallocFailed );
/* Code the OP_Program opcode in the parent VDBE. P4 of the OP_Program
** is a pointer to the sub-vdbe containing the trigger program. */
if( pPrg ){
int bRecursive = (p->zName && 0==(pParse->db->flags&SQLITE_RecTriggers));
sqlite3VdbeAddOp3(v, OP_Program, reg, ignoreJump, ++pParse->nMem);
sqlite3VdbeChangeP4(v, -1, (const char *)pPrg->pProgram, P4_SUBPROGRAM);
VdbeComment(
(v, "Call: %s.%s", (p->zName?p->zName:"fkey"), onErrorText(orconf)));
/* Set the P5 operand of the OP_Program instruction to non-zero if
** recursive invocation of this trigger program is disallowed. Recursive
** invocation is disallowed if (a) the sub-program is really a trigger,
** not a foreign key action, and (b) the flag to enable recursive triggers
** is clear. */
sqlite3VdbeChangeP5(v, (u8)bRecursive);
}
}
/*
** 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.
*/
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;
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
assert( iIdxCur+i!=iDataCur || pPk==pIdx );
if( aRegIdx!=0 && aRegIdx[i]==0 ) continue;
if( pIdx==pPk ) continue;
if( iIdxCur+i==iIdxNoSeek ) continue;
VdbeModuleComment((v, "GenRowIdxDel for %s", pIdx->zName));
r1 = sqlite3GenerateIndexKey(pParse, pIdx, iDataCur, 0, 1,
&iPartIdxLabel, pPrior, r1);
sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1,
pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn);
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
** to false or null. If pIdx is not a partial index, *piPartIdxLabel
** will be set to zero which is an empty label that is ignored by
** sqlite3ResolvePartIdxLabel().
**
** The pPrior and regPrior parameters are used to implement a cache to
** avoid unnecessary register loads. If pPrior is not NULL, then it is
** a pointer to a different index for which an index key has just been
** computed into register regPrior. If the current pIdx index is generating
** its key into the same sequence of registers and if pPrior and pIdx share
** a column in common, then the register corresponding to that column already
** holds the correct value and the loading of that register is skipped.
** This optimization is helpful when doing a DELETE or an INTEGRITY_CHECK
** on a table with multiple indices, and especially with the ROWID or
** PRIMARY KEY columns of the index.
*/
int sqlite3GenerateIndexKey(
Parse *pParse, /* Parsing context */
Index *pIdx, /* The index for which to generate a key */
int iDataCur, /* Cursor number from which to take column data */
int regOut, /* Put the new key into this register if not 0 */
int prefixOnly, /* Compute only a unique prefix of the key */
int *piPartIdxLabel, /* OUT: Jump to this label to skip partial index */
Index *pPrior, /* Previously generated index key */
int regPrior /* Register holding previous generated key */
){
Vdbe *v = pParse->pVdbe;
int j;
int regBase;
int nCol;
if( piPartIdxLabel ){
if( pIdx->pPartIdxWhere ){
*piPartIdxLabel = sqlite3VdbeMakeLabel(v);
pParse->iSelfTab = iDataCur + 1;
sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel,
SQLITE_JUMPIFNULL);
pParse->iSelfTab = 0;
}else{
*piPartIdxLabel = 0;
}
}
nCol = (prefixOnly && pIdx->uniqNotNull) ? pIdx->nKeyCol : pIdx->nColumn;
regBase = sqlite3GetTempRange(pParse, nCol);
if( pPrior && (regBase!=regPrior || pPrior->pPartIdxWhere) ) pPrior = 0;
for(j=0; j<nCol; j++){
if( pPrior
&& pPrior->aiColumn[j]==pIdx->aiColumn[j]
&& pPrior->aiColumn[j]!=XN_EXPR
){
/* This column was already computed by the previous index */
continue;
}
sqlite3ExprCodeLoadIndexColumn(pParse, pIdx, iDataCur, j, regBase+j);
/* If the column affinity is REAL but the number is an integer, then it
** might be stored in the table as an integer (using a compact
** representation) then converted to REAL by an OP_RealAffinity opcode.
** But we are getting ready to store this value back into an index, where
** it should be converted by to INTEGER again. So omit the OP_RealAffinity
** opcode if it is present */
sqlite3VdbeDeletePriorOpcode(v, OP_RealAffinity);
}
if( regOut ){
sqlite3VdbeAddOp3(v, OP_MakeRecord, regBase, nCol, regOut);
if( pIdx->pTable->pSelect ){
const char *zAff = sqlite3IndexAffinityStr(pParse->db, pIdx);
sqlite3VdbeChangeP4(v, -1, zAff, P4_TRANSIENT);
}
}
sqlite3ReleaseTempRange(pParse, regBase, nCol);
return regBase;
}
/*
** Generate code to make sure the file format number is at least minFormat.
** The generated code will increase the file format number if necessary.
*/
void sqlite3MinimumFileFormat(Parse *pParse, int iDb, int minFormat){
Vdbe *v;
v = sqlite3GetVdbe(pParse);
/* The VDBE should have been allocated before this routine is called.
** If that allocation failed, we would have quit before reaching this
** point */
if( ALWAYS(v) ){
int r1 = sqlite3GetTempReg(pParse);
int r2 = sqlite3GetTempReg(pParse);
int j1;
sqlite3VdbeAddOp3(v, OP_ReadCookie, iDb, r1, BTREE_FILE_FORMAT);
sqlite3VdbeUsesBtree(v, iDb);
sqlite3VdbeAddOp2(v, OP_Integer, minFormat, r2);
j1 = sqlite3VdbeAddOp3(v, OP_Ge, r2, 0, r1);
sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT, r2);
sqlite3VdbeJumpHere(v, j1);
sqlite3ReleaseTempReg(pParse, r1);
sqlite3ReleaseTempReg(pParse, r2);
}
}
/*
** Generate code that will open a table for reading.
*/
void sqlite3OpenTable(
Parse *p, /* Generate code into this VDBE */
int iCur, /* The cursor number of the table */
int iDb, /* The database index in sqlite3.aDb[] */
Table *pTab, /* The table to be opened */
int opcode /* OP_OpenRead or OP_OpenWrite */
){
Vdbe *v;
if( IsVirtual(pTab) ) return;
v = sqlite3GetVdbe(p);
assert( opcode==OP_OpenWrite || opcode==OP_OpenRead );
sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName);
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb);
VdbeComment((v, "%s", pTab->zName));
}
/*
** This routine generates VDBE code that causes the deletion of all
** index entries associated with a single row of a single table.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number "iCur".
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number iCur+i for the i-th index.
**
** 3. The "iCur" cursor must be pointing to the row that is to be
** deleted.
*/
void sqlite3GenerateRowIndexDelete(
Parse *pParse, /* Parsing and code generating context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int *aRegIdx /* Only delete if aRegIdx!=0 && aRegIdx[i]>0 */
){
int i;
Index *pIdx;
int r1;
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
if( aRegIdx!=0 && aRegIdx[i-1]==0 ) continue;
r1 = sqlite3GenerateIndexKey(pParse, pIdx, iCur, 0, 0);
sqlite3VdbeAddOp3(pParse->pVdbe, OP_IdxDelete, iCur+i, r1,pIdx->nColumn+1);
}
}
/*
** This routine generates VDBE code that causes a single row of a
** single table to be deleted.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number "base".
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number base+i for the i-th index.
**
** 3. The record number of the row to be deleted must be stored in
** memory cell iRowid.
**
** This routine pops the top of the stack to remove the record number
** and then generates code to remove both the table record and all index
** entries that point to that record.
*/
void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int iRowid, /* Memory cell that contains the rowid to delete */
int count /* Increment the row change counter */
){
int addr;
Vdbe *v;
v = pParse->pVdbe;
addr = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, iRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
if( count ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
}
sqlite3VdbeJumpHere(v, addr);
}
/*
** Generate code for an UPDATE of a virtual table.
**
** There are two possible strategies - the default and the special
** "onepass" strategy. Onepass is only used if the virtual table
** implementation indicates that pWhere may match at most one row.
**
** The default strategy is to create an ephemeral table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row.
** (C) The content of every column in the row.
**
** Then loop through the contents of this ephemeral table executing a
** VUpdate for each row. When finished, drop the ephemeral table.
**
** The "onepass" strategy does not use an ephemeral table. Instead, it
** stores the same values (A, B and C above) in a register array and
** makes a single invocation of VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere, /* WHERE clause of the UPDATE statement */
int onError /* ON CONFLICT strategy */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
WhereInfo *pWInfo;
int nArg = 2 + pTab->nCol; /* Number of arguments to VUpdate */
int regArg; /* First register in VUpdate arg array */
int regRec; /* Register in which to assemble record */
int regRowid; /* Register for ephem table rowid */
int iCsr = pSrc->a[0].iCursor; /* Cursor used for virtual table scan */
int aDummy[2]; /* Unused arg for sqlite3WhereOkOnePass() */
int bOnePass; /* True to use onepass strategy */
int addr; /* Address of OP_OpenEphemeral */
/* Allocate nArg registers to martial the arguments to VUpdate. Then
** create and open the ephemeral table in which the records created from
** these arguments will be temporarily stored. */
assert( v );
ephemTab = pParse->nTab++;
addr= sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, nArg);
regArg = pParse->nMem + 1;
pParse->nMem += nArg;
regRec = ++pParse->nMem;
regRowid = ++pParse->nMem;
/* Start scanning the virtual table */
pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0,0,WHERE_ONEPASS_DESIRED,0);
if( pWInfo==0 ) return;
/* Populate the argument registers. */
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
if( pRowid ){
sqlite3ExprCode(pParse, pRowid, regArg+1);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
}
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
}else{
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
}
}
bOnePass = sqlite3WhereOkOnePass(pWInfo, aDummy);
if( bOnePass ){
/* If using the onepass strategy, no-op out the OP_OpenEphemeral coded
** above. Also, if this is a top-level parse (not a trigger), clear the
** multi-write flag so that the VM does not open a statement journal */
sqlite3VdbeChangeToNoop(v, addr);
if( sqlite3IsToplevel(pParse) ){
pParse->isMultiWrite = 0;
}
}else{
/* Create a record from the argument register contents and insert it into
** the ephemeral table. */
sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
}
if( bOnePass==0 ){
/* End the virtual table scan */
sqlite3WhereEnd(pWInfo);
/* Begin scannning through the ephemeral table. */
addr = sqlite3VdbeAddOp1(v, OP_Rewind, ephemTab); VdbeCoverage(v);
/* Extract arguments from the current row of the ephemeral table and
** invoke the VUpdate method. */
for(i=0; i<nArg; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i, regArg+i);
}
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, nArg, regArg, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
sqlite3MayAbort(pParse);
/* End of the ephemeral table scan. Or, if using the onepass strategy,
** jump to here if the scan visited zero rows. */
if( bOnePass==0 ){
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
}else{
sqlite3WhereEnd(pWInfo);
}
}
/*
** This routine generates VDBE code that causes a single row of a
** single table to be deleted.
**
** The VDBE must be in a particular state when this routine is called.
** These are the requirements:
**
** 1. A read/write cursor pointing to pTab, the table containing the row
** to be deleted, must be opened as cursor number $iCur.
**
** 2. Read/write cursors for all indices of pTab must be open as
** cursor number base+i for the i-th index.
**
** 3. The record number of the row to be deleted must be stored in
** memory cell iRowid.
**
** This routine generates code to remove both the table record and all
** index entries that point to that record.
*/
void sqlite3GenerateRowDelete(
Parse *pParse, /* Parsing context */
Table *pTab, /* Table containing the row to be deleted */
int iCur, /* Cursor number for the table */
int iRowid, /* Memory cell that contains the rowid to delete */
int count, /* If non-zero, increment the row change counter */
Trigger *pTrigger, /* List of triggers to (potentially) fire */
int onconf /* Default ON CONFLICT policy for triggers */
){
Vdbe *v = pParse->pVdbe; /* Vdbe */
int iOld = 0; /* First register in OLD.* array */
int iLabel; /* Label resolved to end of generated code */
/* Vdbe is guaranteed to have been allocated by this stage. */
assert( v );
/* 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(v);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
/* If there are any triggers to fire, allocate a range of registers to
** use for the old.* references in the triggers. */
if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){
u32 mask; /* Mask of OLD.* columns in use */
int iCol; /* Iterator used while populating OLD.* */
/* TODO: Could use temporary registers here. Also could attempt to
** avoid copying the contents of the rowid register. */
mask = sqlite3TriggerColmask(
pParse, pTrigger, 0, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onconf
);
mask |= sqlite3FkOldmask(pParse, pTab);
iOld = pParse->nMem+1;
pParse->nMem += (1 + pTab->nCol);
/* Populate the OLD.* pseudo-table register array. These values will be
** used by any BEFORE and AFTER triggers that exist. */
sqlite3VdbeAddOp2(v, OP_Copy, iRowid, iOld);
for(iCol=0; iCol<pTab->nCol; iCol++){
if( mask==0xffffffff || mask&(1<<iCol) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, iCol, iOld+iCol+1);
}
}
/* Invoke BEFORE DELETE trigger programs. */
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
);
/* Seek the cursor to the row to be deleted again. It may be that
** the BEFORE triggers coded above have already removed the row
** being deleted. Do not attempt to delete the row a second time, and
** do not fire AFTER triggers. */
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, iLabel, iRowid);
/* Do FK processing. This call checks that any FK constraints that
** refer to this table (i.e. constraints attached to other tables)
** are not violated by deleting this row. */
sqlite3FkCheck(pParse, pTab, iOld, 0);
}
/* Delete the index and table entries. Skip this step if pTab is really
** a view (in which case the only effect of the DELETE statement is to
** fire the INSTEAD OF triggers). */
if( pTab->pSelect==0 ){
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, 0);
sqlite3VdbeAddOp2(v, OP_Delete, iCur, (count?OPFLAG_NCHANGE:0));
if( count ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT);
}
}
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just deleted. */
sqlite3FkActions(pParse, pTab, 0, iOld);
/* Invoke AFTER DELETE trigger programs. */
sqlite3CodeRowTrigger(pParse, pTrigger,
TK_DELETE, 0, TRIGGER_AFTER, pTab, iOld, onconf, iLabel
);
/* Jump here if the row had already been deleted before any BEFORE
** trigger programs were invoked. Or if a trigger program throws a
** RAISE(IGNORE) exception. */
sqlite3VdbeResolveLabel(v, iLabel);
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iCur; /* VDBE Cursor number for pTab */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || pTrigger);
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK && pWhere==0 && !pTrigger && !IsVirtual(pTab)
&& 0==sqlite3FkRequired(pParse, pTab, 0, 0)
){
assert( !isView );
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
{
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
int regRowid; /* Actual register containing rowids */
/* Collect rowids of every row to be deleted.
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
pWInfo = sqlite3WhereBegin(
pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0
);
if( pWInfo==0 ) goto delete_from_cleanup;
regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, iRowid, 0);
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
sqlite3WhereEnd(pWInfo);
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order. */
end = sqlite3VdbeMakeLabel(v);
/* 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 ){
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
sqlite3MayAbort(pParse);
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, count, pTrigger, OE_Default);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** 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 */
){
sqlite3 *db = pParse->db; /* Database handle */
Index *pIdx; /* An index to being analyzed */
int iIdxCur; /* Cursor open on index being analyzed */
Vdbe *v; /* The virtual machine being built up */
int i; /* Loop counter */
int topOfLoop; /* The top of the loop */
int endOfLoop; /* The end of the loop */
int jZeroRows = -1; /* Jump from here if number of rows is zero */
int iDb; /* Index of database containing pTab */
int regTabname = iMem++; /* Register containing table name */
int regIdxname = iMem++; /* Register containing index name */
int regSampleno = iMem++; /* Register containing next sample number */
int regCol = iMem++; /* Content of a column analyzed table */
int regRec = iMem++; /* Register holding completed record */
int regTemp = iMem++; /* Temporary use register */
int regRowid = iMem++; /* Rowid for the inserted record */
#ifdef SQLITE_ENABLE_STAT2
int addr = 0; /* Instruction address */
int regTemp2 = iMem++; /* Temporary use register */
int regSamplerecno = iMem++; /* Index of next sample to record */
int regRecno = iMem++; /* Current sample index */
int regLast = iMem++; /* Index of last sample to record */
int regFirst = iMem++; /* Index of first sample to record */
#endif
v = sqlite3GetVdbe(pParse);
if( v==0 || NEVER(pTab==0) ){
return;
}
if( pTab->tnum==0 ){
/* Do not gather statistics on views or virtual tables */
return;
}
if( memcmp(pTab->zName, "sqlite_", 7)==0 ){
/* Do not gather statistics on system tables */
return;
}
assert( sqlite3BtreeHoldsAllMutexes(db) );
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb>=0 );
assert( sqlite3SchemaMutexHeld(db, iDb, 0) );
#ifndef SQLITE_OMIT_AUTHORIZATION
if( sqlite3AuthCheck(pParse, SQLITE_ANALYZE, pTab->zName, 0,
db->aDb[iDb].zName ) ){
return;
}
#endif
/* Establish a read-lock on the table at the shared-cache level. */
sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName);
iIdxCur = pParse->nTab++;
sqlite3VdbeAddOp4(v, OP_String8, 0, regTabname, 0, pTab->zName, 0);
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
int nCol;
KeyInfo *pKey;
if( pOnlyIdx && pOnlyIdx!=pIdx ) continue;
nCol = pIdx->nColumn;
pKey = sqlite3IndexKeyinfo(pParse, pIdx);
if( iMem+1+(nCol*2)>pParse->nMem ){
pParse->nMem = iMem+1+(nCol*2);
}
/* Open a cursor to the index to be analyzed. */
assert( iDb==sqlite3SchemaToIndex(db, pIdx->pSchema) );
sqlite3VdbeAddOp4(v, OP_OpenRead, iIdxCur, pIdx->tnum, iDb,
(char *)pKey, P4_KEYINFO_HANDOFF);
VdbeComment((v, "%s", pIdx->zName));
/* Populate the register containing the index name. */
sqlite3VdbeAddOp4(v, OP_String8, 0, regIdxname, 0, pIdx->zName, 0);
#ifdef SQLITE_ENABLE_STAT2
/* If this iteration of the loop is generating code to analyze the
** first index in the pTab->pIndex list, then register regLast has
** not been populated. In this case populate it now. */
if( pTab->pIndex==pIdx ){
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regSamplerecno);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2-1, regTemp);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES*2, regTemp2);
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regLast);
sqlite3VdbeAddOp2(v, OP_Null, 0, regFirst);
addr = sqlite3VdbeAddOp3(v, OP_Lt, regSamplerecno, 0, regLast);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regFirst);
sqlite3VdbeAddOp3(v, OP_Multiply, regLast, regTemp, regLast);
sqlite3VdbeAddOp2(v, OP_AddImm, regLast, SQLITE_INDEX_SAMPLES*2-2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regLast, regLast);
sqlite3VdbeJumpHere(v, addr);
}
/* Zero the regSampleno and regRecno registers. */
sqlite3VdbeAddOp2(v, OP_Integer, 0, regSampleno);
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRecno);
sqlite3VdbeAddOp2(v, OP_Copy, regFirst, regSamplerecno);
#endif
/* The block of memory cells initialized here is used as follows.
**
** iMem:
** The total number of rows in the table.
**
** iMem+1 .. iMem+nCol:
** Number of distinct entries in index considering the
** left-most N columns only, where N is between 1 and nCol,
** inclusive.
**
** iMem+nCol+1 .. Mem+2*nCol:
** Previous value of indexed columns, from left to right.
**
** Cells iMem through iMem+nCol are initialized to 0. The others are
** initialized to contain an SQL NULL.
*/
for(i=0; i<=nCol; i++){
sqlite3VdbeAddOp2(v, OP_Integer, 0, iMem+i);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp2(v, OP_Null, 0, iMem+nCol+i+1);
}
/* Start the analysis loop. This loop runs through all the entries in
** the index b-tree. */
endOfLoop = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iIdxCur, endOfLoop);
topOfLoop = sqlite3VdbeCurrentAddr(v);
sqlite3VdbeAddOp2(v, OP_AddImm, iMem, 1);
for(i=0; i<nCol; i++){
CollSeq *pColl;
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, regCol);
if( i==0 ){
#ifdef SQLITE_ENABLE_STAT2
/* Check if the record that cursor iIdxCur points to contains a
** value that should be stored in the sqlite_stat2 table. If so,
** store it. */
int ne = sqlite3VdbeAddOp3(v, OP_Ne, regRecno, 0, regSamplerecno);
assert( regTabname+1==regIdxname
&& regTabname+2==regSampleno
&& regTabname+3==regCol
);
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 4, regRec, "aaab", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur+1, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur+1, regRec, regRowid);
/* Calculate new values for regSamplerecno and regSampleno.
**
** sampleno = sampleno + 1
** samplerecno = samplerecno+(remaining records)/(remaining samples)
*/
sqlite3VdbeAddOp2(v, OP_AddImm, regSampleno, 1);
sqlite3VdbeAddOp3(v, OP_Subtract, regRecno, regLast, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp2(v, OP_Integer, SQLITE_INDEX_SAMPLES, regTemp2);
sqlite3VdbeAddOp3(v, OP_Subtract, regSampleno, regTemp2, regTemp2);
sqlite3VdbeAddOp3(v, OP_Divide, regTemp2, regTemp, regTemp);
sqlite3VdbeAddOp3(v, OP_Add, regSamplerecno, regTemp, regSamplerecno);
sqlite3VdbeJumpHere(v, ne);
sqlite3VdbeAddOp2(v, OP_AddImm, regRecno, 1);
#endif
/* Always record the very first row */
sqlite3VdbeAddOp1(v, OP_IfNot, iMem+1);
}
assert( pIdx->azColl!=0 );
assert( pIdx->azColl[i]!=0 );
pColl = sqlite3LocateCollSeq(pParse, pIdx->azColl[i]);
sqlite3VdbeAddOp4(v, OP_Ne, regCol, 0, iMem+nCol+i+1,
(char*)pColl, P4_COLLSEQ);
sqlite3VdbeChangeP5(v, SQLITE_NULLEQ);
}
if( db->mallocFailed ){
/* If a malloc failure has occurred, then the result of the expression
** passed as the second argument to the call to sqlite3VdbeJumpHere()
** below may be negative. Which causes an assert() to fail (or an
** out-of-bounds write if SQLITE_DEBUG is not defined). */
return;
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, endOfLoop);
for(i=0; i<nCol; i++){
int addr2 = sqlite3VdbeCurrentAddr(v) - (nCol*2);
if( i==0 ){
sqlite3VdbeJumpHere(v, addr2-1); /* Set jump dest for the OP_IfNot */
}
sqlite3VdbeJumpHere(v, addr2); /* Set jump dest for the OP_Ne */
sqlite3VdbeAddOp2(v, OP_AddImm, iMem+i+1, 1);
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, i, iMem+nCol+i+1);
}
/* End of the analysis loop. */
sqlite3VdbeResolveLabel(v, endOfLoop);
sqlite3VdbeAddOp2(v, OP_Next, iIdxCur, topOfLoop);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
/* Store the results in sqlite_stat1.
**
** The result is a single row of the sqlite_stat1 table. The first
** two columns are the names of the table and index. The third column
** is a string composed of a list of integer statistics about the
** index. The first integer in the list is the total number of entries
** in the index. There is one additional integer in the list for each
** column of the table. This additional integer is a guess of how many
** rows of the table the index will select. If D is the count of distinct
** values and K is the total number of rows, then the integer is computed
** as:
**
** I = (K+D-1)/D
**
** If K==0 then no entry is made into the sqlite_stat1 table.
** If K>0 then it is always the case the D>0 so division by zero
** is never possible.
*/
sqlite3VdbeAddOp2(v, OP_SCopy, iMem, regSampleno);
if( jZeroRows<0 ){
jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, iMem);
}
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp4(v, OP_String8, 0, regTemp, 0, " ", 0);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
sqlite3VdbeAddOp3(v, OP_Add, iMem, iMem+i+1, regTemp);
sqlite3VdbeAddOp2(v, OP_AddImm, regTemp, -1);
sqlite3VdbeAddOp3(v, OP_Divide, iMem+i+1, regTemp, regTemp);
sqlite3VdbeAddOp1(v, OP_ToInt, regTemp);
sqlite3VdbeAddOp3(v, OP_Concat, regTemp, regSampleno, regSampleno);
}
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
}
/* If the table has no indices, create a single sqlite_stat1 entry
** containing NULL as the index name and the row count as the content.
*/
if( pTab->pIndex==0 ){
sqlite3VdbeAddOp3(v, OP_OpenRead, iIdxCur, pTab->tnum, iDb);
VdbeComment((v, "%s", pTab->zName));
sqlite3VdbeAddOp2(v, OP_Count, iIdxCur, regSampleno);
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur);
jZeroRows = sqlite3VdbeAddOp1(v, OP_IfNot, regSampleno);
}else{
sqlite3VdbeJumpHere(v, jZeroRows);
jZeroRows = sqlite3VdbeAddOp0(v, OP_Goto);
}
sqlite3VdbeAddOp2(v, OP_Null, 0, regIdxname);
sqlite3VdbeAddOp4(v, OP_MakeRecord, regTabname, 3, regRec, "aaa", 0);
sqlite3VdbeAddOp2(v, OP_NewRowid, iStatCur, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, iStatCur, regRec, regRowid);
sqlite3VdbeChangeP5(v, OPFLAG_APPEND);
if( pParse->nMem<regRec ) pParse->nMem = regRec;
sqlite3VdbeJumpHere(v, jZeroRows);
}
/*
** This routine generates code that opens the sqlite_stat1 table for
** writing with cursor iStatCur. If the library was built with the
** SQLITE_ENABLE_STAT2 macro defined, then the sqlite_stat2 table is
** opened for writing using cursor (iStatCur+1)
**
** If the sqlite_stat1 tables does not previously exist, it is created.
** Similarly, if the sqlite_stat2 table does not exist and the library
** is compiled with SQLITE_ENABLE_STAT2 defined, 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_stat1 and (if applicable) sqlite_stat2 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" },
#ifdef SQLITE_ENABLE_STAT2
{ "sqlite_stat2", "tbl,idx,sampleno,sample" },
#endif
};
int aRoot[] = {0, 0};
u8 aCreateTbl[] = {0, 0};
int i;
sqlite3 *db = pParse->db;
Db *pDb;
Vdbe *v = sqlite3GetVdbe(pParse);
if( v==0 ) return;
assert( sqlite3BtreeHoldsAllMutexes(db) );
assert( sqlite3VdbeDb(v)==db );
pDb = &db->aDb[iDb];
for(i=0; i<ArraySize(aTable); i++){
const char *zTab = aTable[i].zName;
Table *pStat;
if( (pStat = sqlite3FindTable(db, zTab, pDb->zName))==0 ){
/* The sqlite_stat[12] table does not exist. Create it. Note that a
** side-effect of the CREATE TABLE statement is to leave the rootpage
** of the new table in register pParse->regRoot. This is important
** because the OpenWrite opcode below will be needing it. */
sqlite3NestedParse(pParse,
"CREATE TABLE %Q.%s(%s)", pDb->zName, zTab, aTable[i].zCols
);
aRoot[i] = pParse->regRoot;
aCreateTbl[i] = 1;
}else{
/* The table already exists. If zWhere is not NULL, delete all entries
** associated with the table zWhere. If zWhere is NULL, delete the
** entire contents of the table. */
aRoot[i] = pStat->tnum;
sqlite3TableLock(pParse, iDb, aRoot[i], 1, zTab);
if( zWhere ){
sqlite3NestedParse(pParse,
"DELETE FROM %Q.%s WHERE %s=%Q", pDb->zName, zTab, zWhereType, zWhere
);
}else{
/* The sqlite_stat[12] table already exists. Delete all rows. */
sqlite3VdbeAddOp2(v, OP_Clear, aRoot[i], iDb);
}
}
}
/* Open the sqlite_stat[12] tables for writing. */
for(i=0; i<ArraySize(aTable); i++){
sqlite3VdbeAddOp3(v, OP_OpenWrite, iStatCur+i, aRoot[i], iDb);
sqlite3VdbeChangeP4(v, -1, (char *)3, P4_INT32);
sqlite3VdbeChangeP5(v, aCreateTbl[i]);
}
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError /* How to handle constraint errors */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addr = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
int nIdx; /* Number of indices that need updating */
int iCur; /* VDBE Cursor number of pTab */
sqlite3 *db; /* The database structure */
int *aRegIdx = 0; /* One register assigned to each index to be updated */
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. */
int chngRowid; /* True if the record number is being changed */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int okOnePass; /* True for one-pass algorithm without the FIFO */
int hasFK; /* True if foreign key processing is required */
#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 */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regNew;
int regOld = 0;
int regRowSet = 0; /* Rowset of rows to be updated */
int regRec; /* Register used for new table record to insert */
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view.
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
isView = pTab->pSelect!=0;
assert( pTrigger || tmask==0 );
#else
# define pTrigger 0
# define isView 0
# define tmask 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
pParse->checkSchema = 1;
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngRowid);
/* Allocate memory for the array aRegIdx[]. There is one entry in the
** array for each index associated with table being updated. Fill in
** the value with a register number for indices that are to be used
** and with zero for unused indices.
*/
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
aRegIdx[j] = reg;
}
/* Begin generating code. */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Allocate required registers. */
regOldRowid = regNewRowid = ++pParse->nMem;
if( pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngRowid || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
regRec = ++pParse->nMem;
/* Start the view context. */
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* If we are trying to update a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Begin the database scan
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0, WHERE_ONEPASS_DESIRED);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Top of the update loop */
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
/* Make cursor iCur point to the record that is being updated. If
** this record does not exist for some reason (deleted by a trigger,
** for example, then jump to the next iteration of the RowSet loop. */
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If the record number will change, set register regNewRowid to
** contain the new value. If the record number is not being modified,
** then regNewRowid is the same register as regOldRowid, which is
** already populated. */
assert( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
/* If there are triggers on this table, populate an array of registers
** with the required old.* column data. */
if( hasFK || pTrigger ){
u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
oldmask |= sqlite3TriggerColmask(pParse,
pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 || oldmask==0xffffffff || (oldmask & (1<<i)) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
/* Populate the array of registers beginning at regNew with the new
** row data. This array is used to check constaints, create the new
** table and index records, and as the values for any new.* references
** made by triggers.
**
** If there are one or more BEFORE triggers, then do not populate the
** registers associated with columns that are (a) not modified by
** this UPDATE statement and (b) not accessed by new.* references. The
** values for registers not modified by the UPDATE must be reloaded from
** the database after the BEFORE triggers are fired anyway (as the trigger
** may have modified them). So not loading those that are not going to
** be used eliminates some redundant opcodes.
*/
newmask = sqlite3TriggerColmask(
pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}else{
j = aXRef[i];
if( j>=0 ){
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
}else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask&(1<<i)) ){
/* This branch loads the value of a column that will not be changed
** into a register. This is done if there are no BEFORE triggers, or
** if there are one or more BEFORE triggers that use this value via
** a new.* reference in a trigger program.
*/
testcase( i==31 );
testcase( i==32 );
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
/* Fire any BEFORE UPDATE triggers. This happens before constraints are
** verified. One could argue that this is wrong.
*/
if( tmask&TRIGGER_BEFORE ){
sqlite3VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
sqlite3TableAffinityStr(v, pTab);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);
/* The row-trigger may have deleted the row being updated. In this
** case, jump to the next row. No updates or AFTER triggers are
** required. This behaviour - what happens when the row being updated
** is deleted or renamed by a BEFORE trigger - is left undefined in the
** documentation.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If it did not delete it, the row-trigger may still have modified
** some of the columns of the row being updated. Load the values for
** all columns not modified by the update statement into their
** registers in case this has happened.
*/
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( !isView ){
int j1; /* Address of jump instruction */
/* Do constraint checks. */
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);
/* Do FK constraint checks. */
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
}
/* Delete the index entries associated with the current record. */
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
/* If changing the record number, delete the old record. */
if( hasFK || chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
}
/* Insert the new index entries and the new record. */
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, aRegIdx, 1, 0, 0);
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just updated. */
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid);
}
}
/* Increment the row counter
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, addr);
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->pTriggerTab && !pParse->nested ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError /* How to handle constraint errors */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addr = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Vdbe *v; /* The virtual database engine */
Index *pIdx; /* For looping over indices */
int nIdx; /* Number of indices that need updating */
int iCur; /* VDBE Cursor number of pTab */
sqlite3 *db; /* The database structure */
int *aRegIdx = 0; /* One register assigned to each index to be updated */
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. */
int chngRowid; /* True if the record number is being changed */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
int openAll = 0; /* True if all indices need to be opened */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int j1; /* Addresses of jump instructions */
int okOnePass; /* True for one-pass algorithm without the FIFO */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* Trying to update a view */
int triggers_exist = 0; /* True if any row triggers exist */
#endif
int iBeginAfterTrigger = 0; /* Address of after trigger program */
int iEndAfterTrigger = 0; /* Exit of after trigger program */
int iBeginBeforeTrigger = 0; /* Address of before trigger program */
int iEndBeforeTrigger = 0; /* Exit of before trigger program */
u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
u32 new_col_mask = 0; /* Mask of NEW.* columns in use */
int newIdx = -1; /* index of trigger "new" temp table */
int oldIdx = -1; /* index of trigger "old" temp table */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid; /* The old rowid */
int regNewRowid; /* The new rowid */
int regData; /* New data for the row */
int regRowSet = 0; /* Rowset of rows to be updated */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pTab, TK_UPDATE, pChanges);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto update_cleanup;
}
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* If there are FOR EACH ROW triggers, allocate cursors for the
** special OLD and NEW tables
*/
if( triggers_exist ){
newIdx = pParse->nTab++;
oldIdx = pParse->nTab++;
}
/* Allocate a cursors for the main database table and for all indices.
** The index cursors might not be used, but if they are used they
** need to occur right after the database cursor. So go ahead and
** allocate enough space, just in case.
*/
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
/* Allocate memory for the array aRegIdx[]. There is one entry in the
** array for each index associated with table being updated. Fill in
** the value with a register number for indices that are to be used
** and with zero for unused indices.
*/
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
aRegIdx[j] = reg;
}
/* Allocate a block of register used to store the change record
** sent to sqlite3GenerateConstraintChecks(). There are either
** one or two registers for holding the rowid. One rowid register
** is used if chngRowid is false and two are used if chngRowid is
** true. Following these are pTab->nCol register holding column
** data.
*/
regOldRowid = regNewRowid = pParse->nMem + 1;
pParse->nMem += pTab->nCol + 1;
if( chngRowid ){
regNewRowid++;
pParse->nMem++;
}
regData = regNewRowid+1;
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Generate the code for triggers.
*/
if( triggers_exist ){
int iGoto;
/* Create pseudo-tables for NEW and OLD
*/
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp2(v, OP_OpenPseudo, oldIdx, 0);
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp2(v, OP_OpenPseudo, newIdx, 0);
iGoto = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
addr = sqlite3VdbeMakeLabel(v);
iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_BEFORE, pTab,
newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
goto update_cleanup;
}
iEndBeforeTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
if( sqlite3CodeRowTrigger(pParse, TK_UPDATE, pChanges, TRIGGER_AFTER, pTab,
newIdx, oldIdx, onError, addr, &old_col_mask, &new_col_mask) ){
goto update_cleanup;
}
iEndAfterTrigger = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0);
sqlite3VdbeJumpHere(v, iGoto);
}
/* If we are trying to update a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
/* Begin the database scan
*/
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0,
WHERE_ONEPASS_DESIRED, 0);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, IsVirtual(pTab)?OP_VRowid:OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Initialize the count of updated rows
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView && !IsVirtual(pTab) ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
/* Jump back to this point if a trigger encounters an IGNORE constraint. */
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
/* Top of the update loop */
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
if( triggers_exist ){
int regRowid;
int regRow;
int regCols;
/* Make cursor iCur point to the record that is being updated.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* Generate the OLD table
*/
regRowid = sqlite3GetTempReg(pParse);
regRow = sqlite3GetTempReg(pParse);
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
if( !old_col_mask ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regRow);
}else{
sqlite3VdbeAddOp2(v, OP_RowData, iCur, regRow);
}
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, regRow, regRowid);
/* Generate the NEW table
*/
if( chngRowid ){
sqlite3ExprCodeAndCache(pParse, pRowidExpr, regRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regRowid);
}
regCols = sqlite3GetTempRange(pParse, pTab->nCol);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
continue;
}
j = aXRef[i];
if( new_col_mask&((u32)1<<i) || new_col_mask==0xffffffff ){
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regCols+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCodeAndCache(pParse, pChanges->a[j].pExpr, regCols+i);
}
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regCols+i);
}
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regCols, pTab->nCol, regRow);
if( !isView ){
sqlite3TableAffinityStr(v, pTab);
sqlite3ExprCacheAffinityChange(pParse, regCols, pTab->nCol);
}
sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol);
/* if( pParse->nErr ) goto update_cleanup; */
sqlite3VdbeAddOp3(v, OP_Insert, newIdx, regRow, regRowid);
sqlite3ReleaseTempReg(pParse, regRowid);
sqlite3ReleaseTempReg(pParse, regRow);
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
}
if( !isView && !IsVirtual(pTab) ){
/* Loop over every record that needs updating. We have to load
** the old data for each record to be updated because some columns
** might not change and we will need to copy the old value.
** Also, the old data is needed to delete the old index entries.
** So make the cursor point at the old record.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
/* If the record number will change, push the record number as it
** will be after the update. (The old record number is currently
** on top of the stack.)
*/
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
/* Compute new data for this record.
*/
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regData+i);
continue;
}
j = aXRef[i];
if( j<0 ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regData+i);
sqlite3ColumnDefault(v, pTab, i);
}else{
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regData+i);
}
}
/* Do constraint checks
*/
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, chngRowid, 1,
onError, addr);
/* Delete the old indices for the current record.
*/
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
/* If changing the record number, delete the old record.
*/
if( chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
/* Create the new index entries and the new record.
*/
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid,
aRegIdx, 1, -1, 0);
}
/* Increment the row counter
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
/* If there are triggers, close all the cursors after each iteration
** through the loop. The fire the after triggers.
*/
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_Close, newIdx, 0);
sqlite3VdbeAddOp2(v, OP_Close, oldIdx, 0);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && !pParse->trigStack && pParse->nested==0 ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
static void codeAttach(
Parse *pParse,
int type,
FuncDef const *pFunc,
Expr *pAuthArg,
Expr *pFilename,
Expr *pDbname,
Expr *pKey
){
int rc;
NameContext sName;
Vdbe *v;
sqlite3* db = pParse->db;
int regArgs;
memset(&sName, 0, sizeof(NameContext));
sName.pParse = pParse;
if(
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
){
pParse->nErr++;
goto attach_end;
}
#ifndef SQLITE_OMIT_AUTHORIZATION
if( pAuthArg ){
char *zAuthArg;
if( pAuthArg->op==TK_STRING ){
zAuthArg = pAuthArg->u.zToken;
}else{
zAuthArg = 0;
}
rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
if(rc!=SQLITE_OK ){
goto attach_end;
}
}
#endif
v = sqlite3GetVdbe(pParse);
regArgs = sqlite3GetTempRange(pParse, 4);
sqlite3ExprCode(pParse, pFilename, regArgs);
sqlite3ExprCode(pParse, pDbname, regArgs+1);
sqlite3ExprCode(pParse, pKey, regArgs+2);
assert( v || db->mallocFailed );
if( v ){
sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-pFunc->nArg, regArgs+3);
assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg );
sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
}
attach_end:
sqlite3ExprDelete(db, pFilename);
sqlite3ExprDelete(db, pDbname);
sqlite3ExprDelete(db, pKey);
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
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 = -1; /* 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 */
int bComplex; /* True if there are triggers or FKs or
** subqueries in the WHERE clause */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
Trigger *pTrigger; /* List of table triggers, if required */
#endif
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0);
isView = pTab->pSelect!=0;
bComplex = pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0);
#else
# define pTrigger 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, (pTrigger?1:0)) ){
goto delete_from_cleanup;
}
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 ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* If we are trying to delete from a view, realize that view into
** an ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iTabCur);
iDataCur = iIdxCur = iTabCur;
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Prior to version 3.6.5,
** this optimization caused the row change count (the value returned by
** API function sqlite3_count_changes) to be set incorrectly. */
if( rcauth==SQLITE_OK
&& pWhere==0
&& !bComplex
&& !IsVirtual(pTab)
#ifdef SQLITE_ENABLE_PREUPDATE_HOOK
&& db->xPreUpdateCallback==0
#endif
){
assert( !isView );
sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName);
if( HasRowid(pTab) ){
sqlite3VdbeAddOp4(v, OP_Clear, pTab->tnum, iDb, memCnt,
pTab->zName, P4_STATIC);
}
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
{
u16 wcf = WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK|WHERE_SEEK_TABLE;
if( sNC.ncFlags & NC_VarSelect ) bComplex = 1;
wcf |= (bComplex ? 0 : WHERE_ONEPASS_MULTIROW);
if( HasRowid(pTab) ){
/* For a rowid table, initialize the RowSet to an empty set */
pPk = 0;
nPk = 1;
iRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
}else{
/* For a WITHOUT ROWID table, create an ephemeral table used to
** hold all primary keys for rows to be deleted. */
pPk = sqlite3PrimaryKeyIndex(pTab);
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
iEphCur = pParse->nTab++;
addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
}
/* Construct a query to find the rowid or primary key for every row
** to be deleted, based on the WHERE clause. Set variable eOnePass
** to indicate the strategy used to implement this delete:
**
** ONEPASS_OFF: Two-pass approach - use a FIFO for rowids/PK values.
** ONEPASS_SINGLE: One-pass approach - at most one row deleted.
** ONEPASS_MULTI: One-pass approach - any number of rows may be deleted.
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, wcf, iTabCur+1);
if( pWInfo==0 ) goto delete_from_cleanup;
eOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
assert( IsVirtual(pTab)==0 || eOnePass!=ONEPASS_MULTI );
assert( IsVirtual(pTab) || bComplex || eOnePass!=ONEPASS_OFF );
/* Keep track of the number of rows to be deleted */
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
/* Extract the rowid or primary key for the current row */
if( pPk ){
for(i=0; i<nPk; i++){
assert( pPk->aiColumn[i]>=0 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur,
pPk->aiColumn[i], iPk+i);
}
iKey = iPk;
}else{
iKey = pParse->nMem + 1;
iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0);
if( iKey>pParse->nMem ) pParse->nMem = iKey;
}
if( eOnePass!=ONEPASS_OFF ){
/* For ONEPASS, no need to store the rowid/primary-key. There is only
** one, so just keep it in its register(s) and fall through to the
** delete code. */
nKey = nPk; /* OP_Found will use an unpacked key */
aToOpen = sqlite3DbMallocRawNN(db, nIdx+2);
if( aToOpen==0 ){
sqlite3WhereEnd(pWInfo);
goto delete_from_cleanup;
}
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0;
if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen);
}else{
if( pPk ){
/* Add the PK key for this row to the temporary table */
iKey = ++pParse->nMem;
nKey = 0; /* Zero tells OP_Found to use a composite key */
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
sqlite3IndexAffinityStr(pParse->db, pPk), nPk);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
}else{
/* Add the rowid of the row to be deleted to the RowSet */
nKey = 1; /* OP_Seek always uses a single rowid */
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
}
}
/* If this DELETE cannot use the ONEPASS strategy, this is the
** end of the WHERE loop */
if( eOnePass!=ONEPASS_OFF ){
addrBypass = sqlite3VdbeMakeLabel(v);
}else{
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) );
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, OPFLAG_FORDELETE,
iTabCur, aToOpen, &iDataCur, &iIdxCur);
assert( pPk || IsVirtual(pTab) || iDataCur==iTabCur );
assert( pPk || IsVirtual(pTab) || iIdxCur==iDataCur+1 );
if( eOnePass==ONEPASS_MULTI ) sqlite3VdbeJumpHere(v, iAddrOnce);
}
/* Set up a loop over the rowids/primary-keys that were found in the
** where-clause loop above.
*/
if( eOnePass!=ONEPASS_OFF ){
assert( nKey==nPk ); /* OP_Found will use an unpacked key */
if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){
assert( pPk!=0 || pTab->pSelect!=0 );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
VdbeCoverage(v);
}
}else if( pPk ){
addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey);
assert( nKey==0 ); /* OP_Found will use a composite key */
}else{
addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
VdbeCoverage(v);
assert( nKey==1 );
}
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iKey, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, OE_Abort);
assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE );
sqlite3MayAbort(pParse);
if( eOnePass==ONEPASS_SINGLE && sqlite3IsToplevel(pParse) ){
pParse->isMultiWrite = 0;
}
}else
#endif
{
int count = (pParse->nested==0); /* True to count changes */
int iIdxNoSeek = -1;
if( bComplex==0 && aiCurOnePass[1]!=iDataCur ){
iIdxNoSeek = aiCurOnePass[1];
}
sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
iKey, nKey, count, OE_Default, eOnePass, iIdxNoSeek);
}
/* End of the loop over all rowids/primary-keys. */
if( eOnePass!=ONEPASS_OFF ){
sqlite3VdbeResolveLabel(v, addrBypass);
sqlite3WhereEnd(pWInfo);
}else if( pPk ){
sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addrLoop);
}else{
sqlite3VdbeGoto(v, addrLoop);
sqlite3VdbeJumpHere(v, addrLoop);
}
/* Close the cursors open on the table and its indexes. */
if( !isView && !IsVirtual(pTab) ){
if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
}
}
} /* End non-truncate path */
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/* Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
sqlite3DbFree(db, aToOpen);
return;
}
/*
** This function is called after an "ALTER TABLE ... ADD" statement
** has been parsed. Argument pColDef contains the text of the new
** column definition.
**
** The Table structure pParse->pNewTable was extended to include
** the new column during parsing.
*/
void sqlite3AlterFinishAddColumn(Parse *pParse, Token *pColDef){
Table *pNew; /* Copy of pParse->pNewTable */
Table *pTab; /* Table being altered */
int iDb; /* Database number */
const char *zDb; /* Database name */
const char *zTab; /* Table name */
char *zCol; /* Null-terminated column definition */
Column *pCol; /* The new column */
Expr *pDflt; /* Default value for the new column */
sqlite3 *db; /* The database connection; */
Vdbe *v = pParse->pVdbe; /* The prepared statement under construction */
db = pParse->db;
if( pParse->nErr || db->mallocFailed ) return;
assert( v!=0 );
pNew = pParse->pNewTable;
assert( pNew );
assert( sqlite3BtreeHoldsAllMutexes(db) );
iDb = sqlite3SchemaToIndex(db, pNew->pSchema);
zDb = db->aDb[iDb].zName;
zTab = &pNew->zName[16]; /* Skip the "sqlite_altertab_" prefix on the name */
pCol = &pNew->aCol[pNew->nCol-1];
pDflt = pCol->pDflt;
pTab = sqlite3FindTable(db, zTab, zDb);
assert( pTab );
#ifndef SQLITE_OMIT_AUTHORIZATION
/* Invoke the authorization callback. */
if( sqlite3AuthCheck(pParse, SQLITE_ALTER_TABLE, zDb, pTab->zName, 0) ){
return;
}
#endif
/* If the default value for the new column was specified with a
** literal NULL, then set pDflt to 0. This simplifies checking
** for an SQL NULL default below.
*/
if( pDflt && pDflt->op==TK_NULL ){
pDflt = 0;
}
/* Check that the new column is not specified as PRIMARY KEY or UNIQUE.
** If there is a NOT NULL constraint, then the default value for the
** column must not be NULL.
*/
if( pCol->colFlags & COLFLAG_PRIMKEY ){
sqlite3ErrorMsg(pParse, "Cannot add a PRIMARY KEY column");
return;
}
if( pNew->pIndex ){
sqlite3ErrorMsg(pParse, "Cannot add a UNIQUE column");
return;
}
if( (db->flags&SQLITE_ForeignKeys) && pNew->pFKey && pDflt ){
sqlite3ErrorMsg(pParse,
"Cannot add a REFERENCES column with non-NULL default value");
return;
}
if( pCol->notNull && !pDflt ){
sqlite3ErrorMsg(pParse,
"Cannot add a NOT NULL column with default value NULL");
return;
}
/* Ensure the default expression is something that sqlite3ValueFromExpr()
** can handle (i.e. not CURRENT_TIME etc.)
*/
if( pDflt ){
sqlite3_value *pVal = 0;
int rc;
rc = sqlite3ValueFromExpr(db, pDflt, SQLITE_UTF8, SQLITE_AFF_BLOB, &pVal);
assert( rc==SQLITE_OK || rc==SQLITE_NOMEM );
if( rc!=SQLITE_OK ){
assert( db->mallocFailed == 1 );
return;
}
if( !pVal ){
sqlite3ErrorMsg(pParse, "Cannot add a column with non-constant default");
return;
}
sqlite3ValueFree(pVal);
}
/* Modify the CREATE TABLE statement. */
zCol = sqlite3DbStrNDup(db, (char*)pColDef->z, pColDef->n);
if( zCol ){
char *zEnd = &zCol[pColDef->n-1];
int savedDbFlags = db->flags;
while( zEnd>zCol && (*zEnd==';' || sqlite3Isspace(*zEnd)) ){
*zEnd-- = '\0';
}
db->flags |= SQLITE_PreferBuiltin;
sqlite3NestedParse(pParse,
"UPDATE \"%w\".%s SET "
"sql = substr(sql,1,%d) || ', ' || %Q || substr(sql,%d) "
"WHERE type = 'table' AND name = %Q",
zDb, SCHEMA_TABLE(iDb), pNew->addColOffset, zCol, pNew->addColOffset+1,
zTab
);
sqlite3DbFree(db, zCol);
db->flags = savedDbFlags;
}
/* If the default value of the new column is NULL, then the file
** format to 2. If the default value of the new column is not NULL,
** the file format be 3. Back when this feature was first added
** in 2006, we went to the trouble to upgrade the file format to the
** minimum support values. But 10-years on, we can assume that all
** extent versions of SQLite support file-format 4, so we always and
** unconditionally upgrade to 4.
*/
sqlite3VdbeAddOp3(v, OP_SetCookie, iDb, BTREE_FILE_FORMAT,
SQLITE_MAX_FILE_FORMAT);
/* Reload the schema of the modified table. */
reloadTableSchema(pParse, pTab, pTab->zName);
}
/*
** Generate code for a DELETE FROM statement.
**
** DELETE FROM table_wxyz WHERE a<5 AND b NOT NULL;
** \________/ \________________/
** pTabList pWhere
*/
void sqlite3DeleteFrom(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table from which we should delete things */
Expr *pWhere /* The WHERE clause. May be null */
){
Vdbe *v; /* The virtual database engine */
Table *pTab; /* The table from which records will be deleted */
const char *zDb; /* Name of database holding pTab */
int end, addr = 0; /* A couple addresses of generated code */
int i; /* Loop counter */
WhereInfo *pWInfo; /* Information about the WHERE clause */
Index *pIdx; /* For looping over indices of the table */
int iCur; /* VDBE Cursor number for pTab */
sqlite3 *db; /* Main database structure */
AuthContext sContext; /* Authorization context */
int oldIdx = -1; /* Cursor for the OLD table of AFTER triggers */
NameContext sNC; /* Name context to resolve expressions in */
int iDb; /* Database number */
int memCnt = -1; /* Memory cell used for change counting */
int rcauth; /* Value returned by authorization callback */
#ifndef SQLITE_OMIT_TRIGGER
int isView; /* True if attempting to delete from a view */
int triggers_exist = 0; /* True if any triggers exist */
#endif
int iBeginAfterTrigger = 0; /* Address of after trigger program */
int iEndAfterTrigger = 0; /* Exit of after trigger program */
int iBeginBeforeTrigger = 0; /* Address of before trigger program */
int iEndBeforeTrigger = 0; /* Exit of before trigger program */
u32 old_col_mask = 0; /* Mask of OLD.* columns in use */
sContext.pParse = 0;
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto delete_from_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to delete. This table has to be
** put in an SrcList structure because some of the subroutines we
** will be calling are designed to work with multiple tables and expect
** an SrcList* parameter instead of just a Table* parameter.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto delete_from_cleanup;
/* Figure out if we have any triggers and if the table being
** deleted from is a view
*/
#ifndef SQLITE_OMIT_TRIGGER
triggers_exist = sqlite3TriggersExist(pTab, TK_DELETE, 0);
isView = pTab->pSelect!=0;
#else
# define triggers_exist 0
# define isView 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3IsReadOnly(pParse, pTab, triggers_exist) ){
goto delete_from_cleanup;
}
iDb = sqlite3SchemaToIndex(db, pTab->pSchema);
assert( iDb<db->nDb );
zDb = db->aDb[iDb].zName;
rcauth = sqlite3AuthCheck(pParse, SQLITE_DELETE, pTab->zName, 0, zDb);
assert( rcauth==SQLITE_OK || rcauth==SQLITE_DENY || rcauth==SQLITE_IGNORE );
if( rcauth==SQLITE_DENY ){
goto delete_from_cleanup;
}
assert(!isView || triggers_exist);
/* If pTab is really a view, make sure it has been initialized.
*/
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto delete_from_cleanup;
}
/* Allocate a cursor used to store the old.* data for a trigger.
*/
if( triggers_exist ){
oldIdx = pParse->nTab++;
}
/* Assign cursor number to the table and all its indices.
*/
assert( pTabList->nSrc==1 );
iCur = pTabList->a[0].iCursor = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
/* Start the view context
*/
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* Begin generating code.
*/
v = sqlite3GetVdbe(pParse);
if( v==0 ){
goto delete_from_cleanup;
}
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, triggers_exist, iDb);
if( triggers_exist ){
int orconf = ((pParse->trigStack)?pParse->trigStack->orconf:OE_Default);
int iGoto = sqlite3VdbeAddOp0(v, OP_Goto);
addr = sqlite3VdbeMakeLabel(v);
iBeginBeforeTrigger = sqlite3VdbeCurrentAddr(v);
(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_BEFORE, pTab,
-1, oldIdx, orconf, addr, &old_col_mask, 0);
iEndBeforeTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
iBeginAfterTrigger = sqlite3VdbeCurrentAddr(v);
(void)sqlite3CodeRowTrigger(pParse, TK_DELETE, 0, TRIGGER_AFTER, pTab, -1,
oldIdx, orconf, addr, &old_col_mask, 0);
iEndAfterTrigger = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, iGoto);
}
/* If we are trying to delete from a view, realize that view into
** a ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
/* Resolve the column names in the WHERE clause.
*/
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto delete_from_cleanup;
}
/* Initialize the counter of the number of rows deleted, if
** we are counting rows.
*/
if( db->flags & SQLITE_CountRows ){
memCnt = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, memCnt);
}
#ifndef SQLITE_OMIT_TRUNCATE_OPTIMIZATION
/* Special case: A DELETE without a WHERE clause deletes everything.
** It is easier just to erase the whole table. Note, however, that
** this means that the row change count will be incorrect.
*/
if( rcauth==SQLITE_OK && pWhere==0 && !triggers_exist && !IsVirtual(pTab) ){
assert( !isView );
sqlite3VdbeAddOp3(v, OP_Clear, pTab->tnum, iDb, memCnt);
if( !pParse->nested ){
sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_STATIC);
}
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
assert( pIdx->pSchema==pTab->pSchema );
sqlite3VdbeAddOp2(v, OP_Clear, pIdx->tnum, iDb);
}
}else
#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
/* The usual case: There is a WHERE clause so we have to scan through
** the table and pick which records to delete.
*/
{
int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
/* Begin the database scan
*/
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0);
if( pWInfo==0 ) goto delete_from_cleanup;
/* Remember the rowid of every item to be deleted.
*/
sqlite3VdbeAddOp2(v, IsVirtual(pTab) ? OP_VRowid : OP_Rowid, iCur, iRowid);
sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iRowid);
if( db->flags & SQLITE_CountRows ){
sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
/* Open the pseudo-table used to store OLD if there are triggers.
*/
if( triggers_exist ){
sqlite3VdbeAddOp2(v, OP_SetNumColumns, 0, pTab->nCol);
sqlite3VdbeAddOp1(v, OP_OpenPseudo, oldIdx);
}
/* Delete every item whose key was written to the list during the
** database scan. We have to delete items after the scan is complete
** because deleting an item can change the scan order.
*/
end = sqlite3VdbeMakeLabel(v);
if( !isView ){
/* Open cursors for the table we are deleting from and
** all its indices.
*/
sqlite3OpenTableAndIndices(pParse, pTab, iCur, OP_OpenWrite);
}
/* This is the beginning of the delete loop. If a trigger encounters
** an IGNORE constraint, it jumps back to here.
*/
if( triggers_exist ){
sqlite3VdbeResolveLabel(v, addr);
}
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
if( triggers_exist ){
int iData = ++pParse->nMem; /* For storing row data of OLD table */
/* If the record is no longer present in the table, jump to the
** next iteration of the loop through the contents of the fifo.
*/
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, iRowid);
/* Populate the OLD.* pseudo-table */
if( old_col_mask ){
sqlite3VdbeAddOp2(v, OP_RowData, iCur, iData);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, iData);
}
sqlite3VdbeAddOp3(v, OP_Insert, oldIdx, iData, iRowid);
/* Jump back and run the BEFORE triggers */
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginBeforeTrigger);
sqlite3VdbeJumpHere(v, iEndBeforeTrigger);
}
if( !isView ){
/* Delete the row */
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
const char *pVtab = (const char *)pTab->pVtab;
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, pVtab, P4_VTAB);
}else
#endif
{
sqlite3GenerateRowDelete(pParse, pTab, iCur, iRowid, pParse->nested==0);
}
}
/* If there are row triggers, close all cursors then invoke
** the AFTER triggers
*/
if( triggers_exist ){
/* Jump back and run the AFTER triggers */
sqlite3VdbeAddOp2(v, OP_Goto, 0, iBeginAfterTrigger);
sqlite3VdbeJumpHere(v, iEndAfterTrigger);
}
/* End of the delete loop */
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeResolveLabel(v, end);
/* Close the cursors after the loop if there are no row triggers */
if( !isView && !IsVirtual(pTab) ){
for(i=1, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
sqlite3VdbeAddOp2(v, OP_Close, iCur + i, pIdx->tnum);
}
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
}
/*
** Return the number of rows that were deleted. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( db->flags & SQLITE_CountRows && pParse->nested==0 && !pParse->trigStack ){
sqlite3VdbeAddOp2(v, OP_ResultRow, memCnt, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows deleted", SQLITE_STATIC);
}
delete_from_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** Process an UPDATE statement.
**
** UPDATE OR IGNORE table_wxyz SET a=b, c=d WHERE e<5 AND f NOT NULL;
** \_______/ \________/ \______/ \________________/
* onError pTabList pChanges pWhere
*/
void sqlite3Update(
Parse *pParse, /* The parser context */
SrcList *pTabList, /* The table in which we should change things */
ExprList *pChanges, /* Things to be changed */
Expr *pWhere, /* The WHERE clause. May be null */
int onError /* How to handle constraint errors */
){
int i, j; /* Loop counters */
Table *pTab; /* The table to be updated */
int addrTop = 0; /* VDBE instruction address of the start of the loop */
WhereInfo *pWInfo; /* 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 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; /* One register assigned to each index to be updated */
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 */
u8 chngKey; /* Either chngPk or chngRowid */
Expr *pRowidExpr = 0; /* Expression defining the new record number */
AuthContext sContext; /* The authorization context */
NameContext sNC; /* The name-context to resolve expressions in */
int iDb; /* Database containing the table being updated */
int okOnePass; /* True for one-pass algorithm without the FIFO */
int hasFK; /* True if foreign key processing is required */
int labelBreak; /* Jump here to break out of UPDATE loop */
int labelContinue; /* Jump here to continue next step of UPDATE loop */
#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 */
/* Register Allocations */
int regRowCount = 0; /* A count of rows changed */
int regOldRowid = 0; /* The old rowid */
int regNewRowid = 0; /* The new rowid */
int regNew = 0; /* Content of the NEW.* table in triggers */
int regOld = 0; /* Content of OLD.* table in triggers */
int regRowSet = 0; /* Rowset of rows to be updated */
int regKey = 0; /* composite PRIMARY KEY value */
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
/* Locate the table which we want to update.
*/
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
/* Figure out if we have any triggers and if the table being
** updated is a view.
*/
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
isView = pTab->pSelect!=0;
assert( pTrigger || tmask==0 );
#else
# define pTrigger 0
# define isView 0
# define tmask 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
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.
*/
pTabList->a[0].iCursor = iBaseCur = iDataCur = pParse->nTab++;
iIdxCur = iDataCur+1;
pPk = HasRowid(pTab) ? 0 : sqlite3PrimaryKeyIndex(pTab);
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
if( IsPrimaryKeyIndex(pIdx) && pPk!=0 ){
iDataCur = pParse->nTab;
pTabList->a[0].iCursor = iDataCur;
}
pParse->nTab++;
}
/* Allocate space for aXRef[], aRegIdx[], and aToOpen[].
** Initialize aXRef[] and aToOpen[] to their default values.
*/
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * (pTab->nCol+nIdx) + nIdx+2 );
if( aXRef==0 ) goto update_cleanup;
aRegIdx = aXRef+pTab->nCol;
aToOpen = (u8*)(aRegIdx+nIdx);
memset(aToOpen, 1, nIdx+1);
aToOpen[nIdx+1] = 0;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
/* Initialize the name-context */
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
/* Resolve the column names in all the expressions of the
** of the UPDATE statement. Also find the column index
** for each column to be updated in the pChanges array. For each
** column to be updated, make sure we have authorization to change
** that column.
*/
chngRowid = chngPk = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else if( pPk && (pTab->aCol[j].colFlags & COLFLAG_PRIMKEY)!=0 ){
chngPk = 1;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( pPk==0 && sqlite3IsRowid(pChanges->a[i].zName) ){
j = -1;
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
pParse->checkSchema = 1;
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
j<0 ? "ROWID" : pTab->aCol[j].zName,
db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
assert( (chngRowid & chngPk)==0 );
assert( chngRowid==0 || chngRowid==1 );
assert( chngPk==0 || chngPk==1 );
chngKey = chngRowid + chngPk;
/* The SET expressions are not actually used inside the WHERE loop.
** So reset the colUsed mask
*/
pTabList->a[0].colUsed = 0;
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngKey);
/* There is one entry in the aRegIdx[] array for each index on the table
** being updated. Fill in aRegIdx[] with a register number that will hold
** the key for accessing each index.
**
** FIXME: Be smarter about omitting indexes that use expressions.
*/
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngKey || hasFK || pIdx->pPartIdxWhere || pIdx==pPk ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nKeyCol; i++){
i16 iIdxCol = pIdx->aiColumn[i];
if( iIdxCol<0 || aXRef[iIdxCol]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
if( reg==0 ) aToOpen[j+1] = 0;
aRegIdx[j] = reg;
}
/* Begin generating code. */
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
/* Allocate required registers. */
if( !IsVirtual(pTab) ){
regRowSet = ++pParse->nMem;
regOldRowid = regNewRowid = ++pParse->nMem;
if( chngPk || pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngKey || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
/* Start the view context. */
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
/* If we are trying to update a view, realize that view into
** an ephemeral table.
*/
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iDataCur);
}
#endif
/* Resolve the column names in all the expressions in the
** WHERE clause.
*/
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
#ifndef SQLITE_OMIT_VIRTUALTABLE
/* Virtual tables must be handled separately */
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere, onError);
goto update_cleanup;
}
#endif
/* Begin the database scan
*/
if( HasRowid(pTab) ){
sqlite3VdbeAddOp3(v, OP_Null, 0, regRowSet, regOldRowid);
pWInfo = sqlite3WhereBegin(
pParse, pTabList, pWhere, 0, 0, WHERE_ONEPASS_DESIRED, iIdxCur
);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
/* Remember the rowid of every item to be updated.
*/
sqlite3VdbeAddOp2(v, OP_Rowid, iDataCur, regOldRowid);
if( !okOnePass ){
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
/* End the database scan loop.
*/
sqlite3WhereEnd(pWInfo);
}else{
int iPk; /* First of nPk memory cells holding PRIMARY KEY value */
i16 nPk; /* Number of components of the PRIMARY KEY */
int addrOpen; /* Address of the OpenEphemeral instruction */
assert( pPk!=0 );
nPk = pPk->nKeyCol;
iPk = pParse->nMem+1;
pParse->nMem += nPk;
regKey = ++pParse->nMem;
iEph = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_Null, 0, iPk);
addrOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEph, nPk);
sqlite3VdbeSetP4KeyInfo(pParse, pPk);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0,
WHERE_ONEPASS_DESIRED, iIdxCur);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
for(i=0; i<nPk; i++){
assert( pPk->aiColumn[i]>=0 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, pPk->aiColumn[i],
iPk+i);
}
if( okOnePass ){
sqlite3VdbeChangeToNoop(v, addrOpen);
nKey = nPk;
regKey = iPk;
}else{
sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, regKey,
sqlite3IndexAffinityStr(db, pPk), nPk);
sqlite3VdbeAddOp2(v, OP_IdxInsert, iEph, regKey);
}
sqlite3WhereEnd(pWInfo);
}
/* Initialize the count of updated rows
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
labelBreak = sqlite3VdbeMakeLabel(v);
if( !isView ){
/*
** Open every index that needs updating. Note that if any
** index could potentially invoke a REPLACE conflict resolution
** action, then we need to open all indices because we might need
** to be deleting some records.
*/
if( onError==OE_Replace ){
memset(aToOpen, 1, nIdx+1);
}else{
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
memset(aToOpen, 1, nIdx+1);
break;
}
}
}
if( okOnePass ){
if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iBaseCur] = 0;
if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iBaseCur] = 0;
}
sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, iBaseCur, aToOpen,
0, 0);
}
/* Top of the update loop */
if( okOnePass ){
if( aToOpen[iDataCur-iBaseCur] && !isView ){
assert( pPk );
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelBreak, regKey, nKey);
VdbeCoverageNeverTaken(v);
}
labelContinue = labelBreak;
sqlite3VdbeAddOp2(v, OP_IsNull, pPk ? regKey : regOldRowid, labelBreak);
VdbeCoverageIf(v, pPk==0);
VdbeCoverageIf(v, pPk!=0);
}else if( pPk ){
labelContinue = sqlite3VdbeMakeLabel(v);
sqlite3VdbeAddOp2(v, OP_Rewind, iEph, labelBreak); VdbeCoverage(v);
addrTop = sqlite3VdbeAddOp2(v, OP_RowKey, iEph, regKey);
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue, regKey, 0);
VdbeCoverage(v);
}else{
labelContinue = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, labelBreak,
regOldRowid);
VdbeCoverage(v);
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
/* If the record number will change, set register regNewRowid to
** contain the new value. If the record number is not being modified,
** then regNewRowid is the same register as regOldRowid, which is
** already populated. */
assert( chngKey || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid); VdbeCoverage(v);
}
/* Compute the old pre-UPDATE content of the row being changed, if that
** information is needed */
if( chngPk || hasFK || pTrigger ){
u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
oldmask |= sqlite3TriggerColmask(pParse,
pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( oldmask==0xffffffff
|| (i<32 && (oldmask & MASKBIT32(i))!=0)
|| (pTab->aCol[i].colFlags & COLFLAG_PRIMKEY)!=0
){
testcase( oldmask!=0xffffffff && i==31 );
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 && pPk==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
/* Populate the array of registers beginning at regNew with the new
** row data. This array is used to check constants, create the new
** table and index records, and as the values for any new.* references
** made by triggers.
**
** If there are one or more BEFORE triggers, then do not populate the
** registers associated with columns that are (a) not modified by
** this UPDATE statement and (b) not accessed by new.* references. The
** values for registers not modified by the UPDATE must be reloaded from
** the database after the BEFORE triggers are fired anyway (as the trigger
** may have modified them). So not loading those that are not going to
** be used eliminates some redundant opcodes.
*/
newmask = sqlite3TriggerColmask(
pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}else{
j = aXRef[i];
if( j>=0 ){
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
}else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask & MASKBIT32(i)) ){
/* This branch loads the value of a column that will not be changed
** into a register. This is done if there are no BEFORE triggers, or
** if there are one or more BEFORE triggers that use this value via
** a new.* reference in a trigger program.
*/
testcase( i==31 );
testcase( i==32 );
sqlite3ExprCodeGetColumnToReg(pParse, pTab, i, iDataCur, regNew+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}
}
}
/* Fire any BEFORE UPDATE triggers. This happens before constraints are
** verified. One could argue that this is wrong.
*/
if( tmask&TRIGGER_BEFORE ){
sqlite3TableAffinity(v, pTab, regNew);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, labelContinue);
/* The row-trigger may have deleted the row being updated. In this
** case, jump to the next row. No updates or AFTER triggers are
** required. This behavior - what happens when the row being updated
** is deleted or renamed by a BEFORE trigger - is left undefined in the
** documentation.
*/
if( pPk ){
sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, labelContinue,regKey,nKey);
VdbeCoverage(v);
}else{
sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, labelContinue, regOldRowid);
VdbeCoverage(v);
}
/* If it did not delete it, the row-trigger may still have modified
** some of the columns of the row being updated. Load the values for
** all columns not modified by the update statement into their
** registers in case this has happened.
*/
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, i, regNew+i);
}
}
}
if( !isView ){
int addr1 = 0; /* Address of jump instruction */
int bReplace = 0; /* True if REPLACE conflict resolution might happen */
/* Do constraint checks. */
assert( regOldRowid>0 );
sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur,
regNewRowid, regOldRowid, chngKey, onError, labelContinue, &bReplace);
/* Do FK constraint checks. */
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0, aXRef, chngKey);
}
/* Delete the index entries associated with the current record. */
if( bReplace || chngKey ){
if( pPk ){
addr1 = sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, 0, regKey, nKey);
}else{
addr1 = sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, 0, regOldRowid);
}
VdbeCoverageNeverTaken(v);
}
sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur, aRegIdx, -1);
/* If changing the record number, delete the old record. */
if( hasFK || chngKey || pPk!=0 ){
sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, 0);
}
if( bReplace || chngKey ){
sqlite3VdbeJumpHere(v, addr1);
}
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid, aXRef, chngKey);
}
/* Insert the new index entries and the new record. */
sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur,
regNewRowid, aRegIdx, 1, 0, 0);
/* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to
** handle rows (possibly in other tables) that refer via a foreign key
** to the row just updated. */
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid, aXRef, chngKey);
}
}
/* Increment the row counter
*/
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, labelContinue);
/* Repeat the above with the next record to be updated, until
** all record selected by the WHERE clause have been updated.
*/
if( okOnePass ){
/* Nothing to do at end-of-loop for a single-pass */
}else if( pPk ){
sqlite3VdbeResolveLabel(v, labelContinue);
sqlite3VdbeAddOp2(v, OP_Next, iEph, addrTop); VdbeCoverage(v);
}else{
sqlite3VdbeGoto(v, labelContinue);
}
sqlite3VdbeResolveLabel(v, labelBreak);
/* Close all tables */
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
assert( aRegIdx );
if( aToOpen[i+1] ){
sqlite3VdbeAddOp2(v, OP_Close, iIdxCur+i, 0);
}
}
if( iDataCur<iIdxCur ) sqlite3VdbeAddOp2(v, OP_Close, iDataCur, 0);
/* Update the sqlite_sequence table by storing the content of the
** maximum rowid counter values recorded while inserting into
** autoincrement tables.
*/
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
/*
** Return the number of rows that were changed. If this routine is
** generating code because of a call to sqlite3NestedParse(), do not
** invoke the callback function.
*/
if( (db->flags&SQLITE_CountRows) && !pParse->pTriggerTab && !pParse->nested ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aXRef); /* Also frees aRegIdx[] and aToOpen[] */
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** This function is called when a row is inserted into or deleted from the
** child table of foreign key constraint pFKey. If an SQL UPDATE is executed
** on the child table of pFKey, this function is invoked twice for each row
** affected - once to "delete" the old row, and then again to "insert" the
** new row.
**
** Each time it is called, this function generates VDBE code to locate the
** row in the parent table that corresponds to the row being inserted into
** or deleted from the child table. If the parent row can be found, no
** special action is taken. Otherwise, if the parent row can *not* be
** found in the parent table:
**
** Operation | FK type | Action taken
** --------------------------------------------------------------------------
** INSERT immediate Increment the "immediate constraint counter".
**
** DELETE immediate Decrement the "immediate constraint counter".
**
** INSERT deferred Increment the "deferred constraint counter".
**
** DELETE deferred Decrement the "deferred constraint counter".
**
** These operations are identified in the comment at the top of this file
** (fkey.c) as "I.1" and "D.1".
*/
static void fkLookupParent(
Parse *pParse, /* Parse context */
int iDb, /* Index of database housing pTab */
Table *pTab, /* Parent table of FK pFKey */
Index *pIdx, /* Unique index on parent key columns in pTab */
FKey *pFKey, /* Foreign key constraint */
int *aiCol, /* Map from parent key columns to child table columns */
int regData, /* Address of array containing child table row */
int nIncr, /* Increment constraint counter by this */
int isIgnore /* If true, pretend pTab contains all NULL values */
){
int i; /* Iterator variable */
Vdbe *v = sqlite3GetVdbe(pParse); /* Vdbe to add code to */
int iCur = pParse->nTab - 1; /* Cursor number to use */
int iOk = sqlite3VdbeMakeLabel(v); /* jump here if parent key found */
/* If nIncr is less than zero, then check at runtime if there are any
** outstanding constraints to resolve. If there are not, there is no need
** to check if deleting this row resolves any outstanding violations.
**
** Check if any of the key columns in the child table row are NULL. If
** any are, then the constraint is considered satisfied. No need to
** search for a matching row in the parent table. */
if( nIncr<0 ){
sqlite3VdbeAddOp2(v, OP_FkIfZero, pFKey->isDeferred, iOk);
}
for(i=0; i<pFKey->nCol; i++){
int iReg = aiCol[i] + regData + 1;
sqlite3VdbeAddOp2(v, OP_IsNull, iReg, iOk);
}
if( isIgnore==0 ){
if( pIdx==0 ){
/* If pIdx is NULL, then the parent key is the INTEGER PRIMARY KEY
** column of the parent table (table pTab). */
int iMustBeInt; /* Address of MustBeInt instruction */
int regTemp = sqlite3GetTempReg(pParse);
/* Invoke MustBeInt to coerce the child key value to an integer (i.e.
** apply the affinity of the parent key). If this fails, then there
** is no matching parent key. Before using MustBeInt, make a copy of
** the value. Otherwise, the value inserted into the child key column
** will have INTEGER affinity applied to it, which may not be correct. */
sqlite3VdbeAddOp2(v, OP_SCopy, aiCol[0]+1+regData, regTemp);
iMustBeInt = sqlite3VdbeAddOp2(v, OP_MustBeInt, regTemp, 0);
/* If the parent table is the same as the child table, and we are about
** to increment the constraint-counter (i.e. this is an INSERT operation),
** then check if the row being inserted matches itself. If so, do not
** increment the constraint-counter. */
if( pTab==pFKey->pFrom && nIncr==1 ){
sqlite3VdbeAddOp3(v, OP_Eq, regData, iOk, regTemp);
}
sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenRead);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regTemp);
sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
sqlite3VdbeJumpHere(v, sqlite3VdbeCurrentAddr(v)-2);
sqlite3VdbeJumpHere(v, iMustBeInt);
sqlite3ReleaseTempReg(pParse, regTemp);
}else{
int nCol = pFKey->nCol;
int regTemp = sqlite3GetTempRange(pParse, nCol);
int regRec = sqlite3GetTempReg(pParse);
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp3(v, OP_OpenRead, iCur, pIdx->tnum, iDb);
sqlite3VdbeChangeP4(v, -1, (char*)pKey, P4_KEYINFO_HANDOFF);
for(i=0; i<nCol; i++){
sqlite3VdbeAddOp2(v, OP_Copy, aiCol[i]+1+regData, regTemp+i);
}
/* If the parent table is the same as the child table, and we are about
** to increment the constraint-counter (i.e. this is an INSERT operation),
** then check if the row being inserted matches itself. If so, do not
** increment the constraint-counter.
**
** If any of the parent-key values are NULL, then the row cannot match
** itself. So set JUMPIFNULL to make sure we do the OP_Found if any
** of the parent-key values are NULL (at this point it is known that
** none of the child key values are).
*/
if( pTab==pFKey->pFrom && nIncr==1 ){
int iJump = sqlite3VdbeCurrentAddr(v) + nCol + 1;
for(i=0; i<nCol; i++){
int iChild = aiCol[i]+1+regData;
int iParent = pIdx->aiColumn[i]+1+regData;
assert( aiCol[i]!=pTab->iPKey );
if( pIdx->aiColumn[i]==pTab->iPKey ){
/* The parent key is a composite key that includes the IPK column */
iParent = regData;
}
sqlite3VdbeAddOp3(v, OP_Ne, iChild, iJump, iParent);
sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL);
}
sqlite3VdbeAddOp2(v, OP_Goto, 0, iOk);
}
sqlite3VdbeAddOp3(v, OP_MakeRecord, regTemp, nCol, regRec);
sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v,pIdx), P4_TRANSIENT);
sqlite3VdbeAddOp4Int(v, OP_Found, iCur, iOk, regRec, 0);
sqlite3ReleaseTempReg(pParse, regRec);
sqlite3ReleaseTempRange(pParse, regTemp, nCol);
}
}
if( !pFKey->isDeferred && !pParse->pToplevel && !pParse->isMultiWrite ){
/* Special case: If this is an INSERT statement that will insert exactly
** one row into the table, raise a constraint immediately instead of
** incrementing a counter. This is necessary as the VM code is being
** generated for will not open a statement transaction. */
assert( nIncr==1 );
sqlite3HaltConstraint(
pParse, OE_Abort, "foreign key constraint failed", P4_STATIC
);
}else{
if( nIncr>0 && pFKey->isDeferred==0 ){
sqlite3ParseToplevel(pParse)->mayAbort = 1;
}
sqlite3VdbeAddOp2(v, OP_FkCounter, pFKey->isDeferred, nIncr);
}
sqlite3VdbeResolveLabel(v, iOk);
sqlite3VdbeAddOp1(v, OP_Close, iCur);
}
static void updateVirtualTable(
Parse *pParse,
SrcList *pSrc,
Table *pTab,
ExprList *pChanges,
Expr *pRowid,
int *aXRef,
Expr *pWhere
){
Vdbe *v = pParse->pVdbe;
ExprList *pEList = 0;
Select *pSelect = 0;
Expr *pExpr;
int ephemTab;
int i;
int addr;
int iReg;
sqlite3 *db = pParse->db;
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
SelectDest dest;
pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_"));
if( pRowid ){
pEList = sqlite3ExprListAppend(pParse, pEList,
sqlite3ExprDup(db, pRowid, 0));
}
assert( pTab->iPKey<0 );
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
}else{
pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName);
}
pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
}
pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
assert( v );
ephemTab = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
sqlite3Select(pParse, pSelect, &dest);
iReg = ++pParse->nMem;
pParse->nMem += pTab->nCol+1;
addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, 0, iReg);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
for(i=0; i<pTab->nCol; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
sqlite3SelectDelete(db, pSelect);
}
/*
** Generate code for an UPDATE of a virtual table.
**
** The strategy is that we create an ephemerial table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row. (note1)
** (C) The content of every column in the row.
**
** Then we loop over this ephemeral table and for each row in
** the ephermeral table call VUpdate.
**
** When finished, drop the ephemeral table.
**
** (note1) Actually, if we know in advance that (A) is always the same
** as (B) we only store (A), then duplicate (A) when pulling
** it out of the ephemeral table before calling VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere /* WHERE clause of the UPDATE statement */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
ExprList *pEList = 0; /* The result set of the SELECT statement */
Select *pSelect = 0; /* The SELECT statement */
Expr *pExpr; /* Temporary expression */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
int addr; /* Address of top of loop */
int iReg; /* First register in set passed to OP_VUpdate */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
SelectDest dest;
/* Construct the SELECT statement that will find the new values for
** all updated rows.
*/
pEList = sqlite3ExprListAppend(pParse, 0, sqlite3Expr(db, TK_ID, "_rowid_"));
if( pRowid ){
pEList = sqlite3ExprListAppend(pParse, pEList,
sqlite3ExprDup(db, pRowid, 0));
}
assert( pTab->iPKey<0 );
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
pExpr = sqlite3ExprDup(db, pChanges->a[aXRef[i]].pExpr, 0);
}else{
pExpr = sqlite3Expr(db, TK_ID, pTab->aCol[i].zName);
}
pEList = sqlite3ExprListAppend(pParse, pEList, pExpr);
}
pSelect = sqlite3SelectNew(pParse, pEList, pSrc, pWhere, 0, 0, 0, 0, 0, 0);
/* Create the ephemeral table into which the update results will
** be stored.
*/
assert( v );
ephemTab = pParse->nTab++;
sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, pTab->nCol+1+(pRowid!=0));
sqlite3VdbeChangeP5(v, BTREE_UNORDERED);
/* fill the ephemeral table
*/
sqlite3SelectDestInit(&dest, SRT_Table, ephemTab);
sqlite3Select(pParse, pSelect, &dest);
/* Generate code to scan the ephemeral table and call VUpdate. */
iReg = ++pParse->nMem;
pParse->nMem += pTab->nCol+1;
addr = sqlite3VdbeAddOp2(v, OP_Rewind, ephemTab, 0);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, 0, iReg);
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, (pRowid?1:0), iReg+1);
for(i=0; i<pTab->nCol; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i+1+(pRowid!=0), iReg+2+i);
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, pTab->nCol+2, iReg, pVTab, P4_VTAB);
sqlite3MayAbort(pParse);
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
/* Cleanup */
sqlite3SelectDelete(db, pSelect);
}
/*
** This procedure generates VDBE code for a single invocation of either the
** sqlite_detach() or sqlite_attach() SQL user functions.
*/
static void codeAttach(
Parse *pParse, /* The parser context */
int type, /* Either SQLITE_ATTACH or SQLITE_DETACH */
FuncDef *pFunc, /* FuncDef wrapper for detachFunc() or attachFunc() */
Expr *pAuthArg, /* Expression to pass to authorization callback */
Expr *pFilename, /* Name of database file */
Expr *pDbname, /* Name of the database to use internally */
Expr *pKey /* Database key for encryption extension */
){
int rc;
NameContext sName;
Vdbe *v;
sqlite3* db = pParse->db;
int regArgs;
memset(&sName, 0, sizeof(NameContext));
sName.pParse = pParse;
if(
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
){
pParse->nErr++;
goto attach_end;
}
#ifndef SQLITE_OMIT_AUTHORIZATION
if( pAuthArg ){
char *zAuthArg = pAuthArg->u.zToken;
if( NEVER(zAuthArg==0) ){
goto attach_end;
}
rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
if(rc!=SQLITE_OK ){
goto attach_end;
}
}
#endif /* SQLITE_OMIT_AUTHORIZATION */
v = sqlite3GetVdbe(pParse);
regArgs = sqlite3GetTempRange(pParse, 4);
sqlite3ExprCode(pParse, pFilename, regArgs);
sqlite3ExprCode(pParse, pDbname, regArgs+1);
sqlite3ExprCode(pParse, pKey, regArgs+2);
assert( v || db->mallocFailed );
if( v ){
sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-pFunc->nArg, regArgs+3);
assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg );
sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg));
sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
/* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
** statement only). For DETACH, set it to false (expire all existing
** statements).
*/
sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
}
attach_end:
sqlite3ExprDelete(db, pFilename);
sqlite3ExprDelete(db, pDbname);
sqlite3ExprDelete(db, pKey);
}
void sqlite3Update(
Parse *pParse,
SrcList *pTabList,
ExprList *pChanges,
Expr *pWhere,
int onError
){
int i, j;
Table *pTab;
int addr = 0;
WhereInfo *pWInfo;
Vdbe *v;
Index *pIdx;
int nIdx;
int iCur;
sqlite3 *db;
int *aRegIdx = 0;
int *aXRef = 0;
int chngRowid;
Expr *pRowidExpr = 0;
int openAll = 0;
AuthContext sContext;
NameContext sNC;
int iDb;
int okOnePass;
int hasFK;
#ifndef SQLITE_OMIT_TRIGGER
int isView;
Trigger *pTrigger;
int tmask;
#endif
int newmask;
int regRowCount = 0;
int regOldRowid;
int regNewRowid;
int regNew;
int regOld = 0;
int regRowSet = 0;
memset(&sContext, 0, sizeof(sContext));
db = pParse->db;
if( pParse->nErr || db->mallocFailed ){
goto update_cleanup;
}
assert( pTabList->nSrc==1 );
pTab = sqlite3SrcListLookup(pParse, pTabList);
if( pTab==0 ) goto update_cleanup;
iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema);
#ifndef SQLITE_OMIT_TRIGGER
pTrigger = sqlite3TriggersExist(pParse, pTab, TK_UPDATE, pChanges, &tmask);
isView = pTab->pSelect!=0;
assert( pTrigger || tmask==0 );
#else
# define pTrigger 0
# define isView 0
# define tmask 0
#endif
#ifdef SQLITE_OMIT_VIEW
# undef isView
# define isView 0
#endif
if( sqlite3ViewGetColumnNames(pParse, pTab) ){
goto update_cleanup;
}
if( sqlite3IsReadOnly(pParse, pTab, tmask) ){
goto update_cleanup;
}
aXRef = sqlite3DbMallocRaw(db, sizeof(int) * pTab->nCol );
if( aXRef==0 ) goto update_cleanup;
for(i=0; i<pTab->nCol; i++) aXRef[i] = -1;
pTabList->a[0].iCursor = iCur = pParse->nTab++;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
pParse->nTab++;
}
memset(&sNC, 0, sizeof(sNC));
sNC.pParse = pParse;
sNC.pSrcList = pTabList;
chngRowid = 0;
for(i=0; i<pChanges->nExpr; i++){
if( sqlite3ResolveExprNames(&sNC, pChanges->a[i].pExpr) ){
goto update_cleanup;
}
for(j=0; j<pTab->nCol; j++){
if( sqlite3StrICmp(pTab->aCol[j].zName, pChanges->a[i].zName)==0 ){
if( j==pTab->iPKey ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}
aXRef[j] = i;
break;
}
}
if( j>=pTab->nCol ){
if( sqlite3IsRowid(pChanges->a[i].zName) ){
chngRowid = 1;
pRowidExpr = pChanges->a[i].pExpr;
}else{
sqlite3ErrorMsg(pParse, "no such column: %s", pChanges->a[i].zName);
pParse->checkSchema = 1;
goto update_cleanup;
}
}
#ifndef SQLITE_OMIT_AUTHORIZATION
{
int rc;
rc = sqlite3AuthCheck(pParse, SQLITE_UPDATE, pTab->zName,
pTab->aCol[j].zName, db->aDb[iDb].zName);
if( rc==SQLITE_DENY ){
goto update_cleanup;
}else if( rc==SQLITE_IGNORE ){
aXRef[j] = -1;
}
}
#endif
}
hasFK = sqlite3FkRequired(pParse, pTab, aXRef, chngRowid);
for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){}
if( nIdx>0 ){
aRegIdx = sqlite3DbMallocRaw(db, sizeof(Index*) * nIdx );
if( aRegIdx==0 ) goto update_cleanup;
}
for(j=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, j++){
int reg;
if( chngRowid ){
reg = ++pParse->nMem;
}else{
reg = 0;
for(i=0; i<pIdx->nColumn; i++){
if( aXRef[pIdx->aiColumn[i]]>=0 ){
reg = ++pParse->nMem;
break;
}
}
}
aRegIdx[j] = reg;
}
v = sqlite3GetVdbe(pParse);
if( v==0 ) goto update_cleanup;
if( pParse->nested==0 ) sqlite3VdbeCountChanges(v);
sqlite3BeginWriteOperation(pParse, 1, iDb);
#ifndef SQLITE_OMIT_VIRTUALTABLE
if( IsVirtual(pTab) ){
updateVirtualTable(pParse, pTabList, pTab, pChanges, pRowidExpr, aXRef,
pWhere);
pWhere = 0;
pTabList = 0;
goto update_cleanup;
}
#endif
regOldRowid = regNewRowid = ++pParse->nMem;
if( pTrigger || hasFK ){
regOld = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
}
if( chngRowid || pTrigger || hasFK ){
regNewRowid = ++pParse->nMem;
}
regNew = pParse->nMem + 1;
pParse->nMem += pTab->nCol;
if( isView ){
sqlite3AuthContextPush(pParse, &sContext, pTab->zName);
}
#if !defined(SQLITE_OMIT_VIEW) && !defined(SQLITE_OMIT_TRIGGER)
if( isView ){
sqlite3MaterializeView(pParse, pTab, pWhere, iCur);
}
#endif
if( sqlite3ResolveExprNames(&sNC, pWhere) ){
goto update_cleanup;
}
sqlite3VdbeAddOp2(v, OP_Null, 0, regOldRowid);
pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere,0, WHERE_ONEPASS_DESIRED);
if( pWInfo==0 ) goto update_cleanup;
okOnePass = pWInfo->okOnePass;
sqlite3VdbeAddOp2(v, OP_Rowid, iCur, regOldRowid);
if( !okOnePass ){
regRowSet = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_RowSetAdd, regRowSet, regOldRowid);
}
sqlite3WhereEnd(pWInfo);
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab ){
regRowCount = ++pParse->nMem;
sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount);
}
if( !isView ){
if( !okOnePass ) sqlite3OpenTable(pParse, iCur, iDb, pTab, OP_OpenWrite);
if( onError==OE_Replace ){
openAll = 1;
}else{
openAll = 0;
for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
if( pIdx->onError==OE_Replace ){
openAll = 1;
break;
}
}
}
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx);
sqlite3VdbeAddOp4(v, OP_OpenWrite, iCur+i+1, pIdx->tnum, iDb,
(char*)pKey, P4_KEYINFO_HANDOFF);
assert( pParse->nTab>iCur+i+1 );
}
}
}
if( okOnePass ){
int a1 = sqlite3VdbeAddOp1(v, OP_NotNull, regOldRowid);
addr = sqlite3VdbeAddOp0(v, OP_Goto);
sqlite3VdbeJumpHere(v, a1);
}else{
addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, regRowSet, 0, regOldRowid);
}
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
assert( chngRowid || pTrigger || hasFK || regOldRowid==regNewRowid );
if( chngRowid ){
sqlite3ExprCode(pParse, pRowidExpr, regNewRowid);
sqlite3VdbeAddOp1(v, OP_MustBeInt, regNewRowid);
}
if( hasFK || pTrigger ){
u32 oldmask = (hasFK ? sqlite3FkOldmask(pParse, pTab) : 0);
oldmask |= sqlite3TriggerColmask(pParse,
pTrigger, pChanges, 0, TRIGGER_BEFORE|TRIGGER_AFTER, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 || oldmask==0xffffffff || (i<32 && (oldmask & (1<<i))) ){
sqlite3ExprCodeGetColumnOfTable(v, pTab, iCur, i, regOld+i);
}else{
sqlite3VdbeAddOp2(v, OP_Null, 0, regOld+i);
}
}
if( chngRowid==0 ){
sqlite3VdbeAddOp2(v, OP_Copy, regOldRowid, regNewRowid);
}
}
newmask = sqlite3TriggerColmask(
pParse, pTrigger, pChanges, 1, TRIGGER_BEFORE, pTab, onError
);
for(i=0; i<pTab->nCol; i++){
if( i==pTab->iPKey ){
sqlite3VdbeAddOp2(v, OP_Null, 0, regNew+i);
}else{
j = aXRef[i];
if( j>=0 ){
sqlite3ExprCode(pParse, pChanges->a[j].pExpr, regNew+i);
}else if( 0==(tmask&TRIGGER_BEFORE) || i>31 || (newmask&(1<<i)) ){
testcase( i==31 );
testcase( i==32 );
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( tmask&TRIGGER_BEFORE ){
sqlite3VdbeAddOp2(v, OP_Affinity, regNew, pTab->nCol);
sqlite3TableAffinityStr(v, pTab);
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_BEFORE, pTab, regOldRowid, onError, addr);
sqlite3VdbeAddOp3(v, OP_NotExists, iCur, addr, regOldRowid);
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]<0 && i!=pTab->iPKey ){
sqlite3VdbeAddOp3(v, OP_Column, iCur, i, regNew+i);
sqlite3ColumnDefault(v, pTab, i, regNew+i);
}
}
}
if( !isView ){
int j1;
sqlite3GenerateConstraintChecks(pParse, pTab, iCur, regNewRowid,
aRegIdx, (chngRowid?regOldRowid:0), 1, onError, addr, 0);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, regOldRowid, 0);
}
j1 = sqlite3VdbeAddOp3(v, OP_NotExists, iCur, 0, regOldRowid);
sqlite3GenerateRowIndexDelete(pParse, pTab, iCur, aRegIdx);
if( hasFK || chngRowid ){
sqlite3VdbeAddOp2(v, OP_Delete, iCur, 0);
}
sqlite3VdbeJumpHere(v, j1);
if( hasFK ){
sqlite3FkCheck(pParse, pTab, 0, regNewRowid);
}
sqlite3CompleteInsertion(pParse, pTab, iCur, regNewRowid, aRegIdx, 1, 0, 0);
if( hasFK ){
sqlite3FkActions(pParse, pTab, pChanges, regOldRowid);
}
}
if( (db->flags & SQLITE_CountRows) && !pParse->pTriggerTab){
sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1);
}
sqlite3CodeRowTrigger(pParse, pTrigger, TK_UPDATE, pChanges,
TRIGGER_AFTER, pTab, regOldRowid, onError, addr);
sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
sqlite3VdbeJumpHere(v, addr);
for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){
if( openAll || aRegIdx[i]>0 ){
sqlite3VdbeAddOp2(v, OP_Close, iCur+i+1, 0);
}
}
sqlite3VdbeAddOp2(v, OP_Close, iCur, 0);
if( pParse->nested==0 && pParse->pTriggerTab==0 ){
sqlite3AutoincrementEnd(pParse);
}
if( (db->flags&SQLITE_CountRows) && !pParse->pTriggerTab && !pParse->nested ){
sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1);
sqlite3VdbeSetNumCols(v, 1);
sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows updated", SQLITE_STATIC);
}
update_cleanup:
sqlite3AuthContextPop(&sContext);
sqlite3DbFree(db, aRegIdx);
sqlite3DbFree(db, aXRef);
sqlite3SrcListDelete(db, pTabList);
sqlite3ExprListDelete(db, pChanges);
sqlite3ExprDelete(db, pWhere);
return;
}
/*
** This procedure generates VDBE code for a single invocation of either the
** sqlite_detach() or sqlite_attach() SQL user functions.
*/
static void codeAttach(
Parse *pParse, /* The parser context */
int type, /* Either SQLITE_ATTACH or SQLITE_DETACH */
const char *zFunc, /* Either "sqlite_attach" or "sqlite_detach */
int nFunc, /* Number of args to pass to zFunc */
Expr *pAuthArg, /* Expression to pass to authorization callback */
Expr *pFilename, /* Name of database file */
Expr *pDbname, /* Name of the database to use internally */
Expr *pKey /* Database key for encryption extension */
){
int rc;
NameContext sName;
Vdbe *v;
FuncDef *pFunc;
sqlite3* db = pParse->db;
int regArgs;
#ifndef SQLITE_OMIT_AUTHORIZATION
assert( db->mallocFailed || pAuthArg );
if( pAuthArg ){
char *zAuthArg = sqlite3NameFromToken(db, &pAuthArg->span);
if( !zAuthArg ){
goto attach_end;
}
rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
sqlite3_free(zAuthArg);
if(rc!=SQLITE_OK ){
goto attach_end;
}
}
#endif /* SQLITE_OMIT_AUTHORIZATION */
memset(&sName, 0, sizeof(NameContext));
sName.pParse = pParse;
if(
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) ||
SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey))
){
pParse->nErr++;
goto attach_end;
}
v = sqlite3GetVdbe(pParse);
regArgs = sqlite3GetTempRange(pParse, 3);
sqlite3ExprCode(pParse, pFilename, regArgs);
sqlite3ExprCode(pParse, pDbname, regArgs+1);
sqlite3ExprCode(pParse, pKey, regArgs+2);
assert( v || db->mallocFailed );
if( v ){
sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-nFunc, regArgs);
sqlite3VdbeChangeP5(v, nFunc);
pFunc = sqlite3FindFunction(db, zFunc, strlen(zFunc), nFunc, SQLITE_UTF8,0);
sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF);
/* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this
** statement only). For DETACH, set it to false (expire all existing
** statements).
*/
sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH));
}
attach_end:
sqlite3ExprDelete(pFilename);
sqlite3ExprDelete(pDbname);
sqlite3ExprDelete(pKey);
}
/*
** Generate code for an UPDATE of a virtual table.
**
** There are two possible strategies - the default and the special
** "onepass" strategy. Onepass is only used if the virtual table
** implementation indicates that pWhere may match at most one row.
**
** The default strategy is to create an ephemeral table that contains
** for each row to be changed:
**
** (A) The original rowid of that row.
** (B) The revised rowid for the row.
** (C) The content of every column in the row.
**
** Then loop through the contents of this ephemeral table executing a
** VUpdate for each row. When finished, drop the ephemeral table.
**
** The "onepass" strategy does not use an ephemeral table. Instead, it
** stores the same values (A, B and C above) in a register array and
** makes a single invocation of VUpdate.
*/
static void updateVirtualTable(
Parse *pParse, /* The parsing context */
SrcList *pSrc, /* The virtual table to be modified */
Table *pTab, /* The virtual table */
ExprList *pChanges, /* The columns to change in the UPDATE statement */
Expr *pRowid, /* Expression used to recompute the rowid */
int *aXRef, /* Mapping from columns of pTab to entries in pChanges */
Expr *pWhere, /* WHERE clause of the UPDATE statement */
int onError /* ON CONFLICT strategy */
){
Vdbe *v = pParse->pVdbe; /* Virtual machine under construction */
int ephemTab; /* Table holding the result of the SELECT */
int i; /* Loop counter */
sqlite3 *db = pParse->db; /* Database connection */
const char *pVTab = (const char*)sqlite3GetVTable(db, pTab);
WhereInfo *pWInfo;
int nArg = 2 + pTab->nCol; /* Number of arguments to VUpdate */
int regArg; /* First register in VUpdate arg array */
int regRec; /* Register in which to assemble record */
int regRowid; /* Register for ephem table rowid */
int iCsr = pSrc->a[0].iCursor; /* Cursor used for virtual table scan */
int aDummy[2]; /* Unused arg for sqlite3WhereOkOnePass() */
int eOnePass; /* True to use onepass strategy */
int addr; /* Address of OP_OpenEphemeral */
/* Allocate nArg registers in which to gather the arguments for VUpdate. Then
** create and open the ephemeral table in which the records created from
** these arguments will be temporarily stored. */
assert( v );
ephemTab = pParse->nTab++;
addr= sqlite3VdbeAddOp2(v, OP_OpenEphemeral, ephemTab, nArg);
regArg = pParse->nMem + 1;
pParse->nMem += nArg;
regRec = ++pParse->nMem;
regRowid = ++pParse->nMem;
/* Start scanning the virtual table */
pWInfo = sqlite3WhereBegin(pParse, pSrc, pWhere, 0,0,WHERE_ONEPASS_DESIRED,0);
if( pWInfo==0 ) return;
/* Populate the argument registers. */
for(i=0; i<pTab->nCol; i++){
if( aXRef[i]>=0 ){
sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
}else{
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG);/* Enable sqlite3_vtab_nochange() */
}
}
if( HasRowid(pTab) ){
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
if( pRowid ){
sqlite3ExprCode(pParse, pRowid, regArg+1);
}else{
sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
}
}else{
Index *pPk; /* PRIMARY KEY index */
i16 iPk; /* PRIMARY KEY column */
pPk = sqlite3PrimaryKeyIndex(pTab);
assert( pPk!=0 );
assert( pPk->nKeyCol==1 );
iPk = pPk->aiColumn[0];
sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, iPk, regArg);
sqlite3VdbeAddOp2(v, OP_SCopy, regArg+2+iPk, regArg+1);
}
eOnePass = sqlite3WhereOkOnePass(pWInfo, aDummy);
/* There is no ONEPASS_MULTI on virtual tables */
assert( eOnePass==ONEPASS_OFF || eOnePass==ONEPASS_SINGLE );
if( eOnePass ){
/* If using the onepass strategy, no-op out the OP_OpenEphemeral coded
** above. */
sqlite3VdbeChangeToNoop(v, addr);
sqlite3VdbeAddOp1(v, OP_Close, iCsr);
}else{
/* Create a record from the argument register contents and insert it into
** the ephemeral table. */
sqlite3MultiWrite(pParse);
sqlite3VdbeAddOp3(v, OP_MakeRecord, regArg, nArg, regRec);
#ifdef SQLITE_DEBUG
/* Signal an assert() within OP_MakeRecord that it is allowed to
** accept no-change records with serial_type 10 */
sqlite3VdbeChangeP5(v, OPFLAG_NOCHNG_MAGIC);
#endif
sqlite3VdbeAddOp2(v, OP_NewRowid, ephemTab, regRowid);
sqlite3VdbeAddOp3(v, OP_Insert, ephemTab, regRec, regRowid);
}
if( eOnePass==ONEPASS_OFF ){
/* End the virtual table scan */
sqlite3WhereEnd(pWInfo);
/* Begin scannning through the ephemeral table. */
addr = sqlite3VdbeAddOp1(v, OP_Rewind, ephemTab); VdbeCoverage(v);
/* Extract arguments from the current row of the ephemeral table and
** invoke the VUpdate method. */
for(i=0; i<nArg; i++){
sqlite3VdbeAddOp3(v, OP_Column, ephemTab, i, regArg+i);
}
}
sqlite3VtabMakeWritable(pParse, pTab);
sqlite3VdbeAddOp4(v, OP_VUpdate, 0, nArg, regArg, pVTab, P4_VTAB);
sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError);
sqlite3MayAbort(pParse);
/* End of the ephemeral table scan. Or, if using the onepass strategy,
** jump to here if the scan visited zero rows. */
if( eOnePass==ONEPASS_OFF ){
sqlite3VdbeAddOp2(v, OP_Next, ephemTab, addr+1); VdbeCoverage(v);
sqlite3VdbeJumpHere(v, addr);
sqlite3VdbeAddOp2(v, OP_Close, ephemTab, 0);
}else{
sqlite3WhereEnd(pWInfo);
}
}
