mirror of
https://github.com/sqlite/sqlite.git
synced 2025-11-12 13:01:09 +03:00
Merge in performance enhancements from trunk.
FossilOrigin-Name: fc9ae839569eb28eb734c52d95676c59b2e27494
This commit is contained in:
248
src/delete.c
248
src/delete.c
@@ -227,20 +227,34 @@ void sqlite3DeleteFrom(
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Vdbe *v; /* The virtual database engine */
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Table *pTab; /* The table from which records will be deleted */
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const char *zDb; /* Name of database holding pTab */
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int end, addr = 0; /* A couple addresses of generated code */
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int i; /* Loop counter */
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WhereInfo *pWInfo; /* Information about the WHERE clause */
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Index *pIdx; /* For looping over indices of the table */
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int iTabCur; /* Cursor number for the table */
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int iDataCur; /* VDBE cursor for the canonical data source */
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int iIdxCur; /* Cursor number of the first index */
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int nIdx; /* Number of indices */
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sqlite3 *db; /* Main database structure */
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AuthContext sContext; /* Authorization context */
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NameContext sNC; /* Name context to resolve expressions in */
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int iDb; /* Database number */
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int memCnt = -1; /* Memory cell used for change counting */
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int rcauth; /* Value returned by authorization callback */
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int okOnePass; /* True for one-pass algorithm without the FIFO */
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int aiCurOnePass[2]; /* The write cursors opened by WHERE_ONEPASS */
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u8 *aToOpen = 0; /* Open cursor iTabCur+j if aToOpen[j] is true */
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Index *pPk; /* The PRIMARY KEY index on the table */
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int iPk = 0; /* First of nPk registers holding PRIMARY KEY value */
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i16 nPk = 1; /* Number of columns in the PRIMARY KEY */
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int iKey; /* Memory cell holding key of row to be deleted */
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i16 nKey; /* Number of memory cells in the row key */
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int iEphCur = 0; /* Ephemeral table holding all primary key values */
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int iRowSet = 0; /* Register for rowset of rows to delete */
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int addrBypass = 0; /* Address of jump over the delete logic */
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int addrLoop = 0; /* Top of the delete loop */
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int addrDelete = 0; /* Jump directly to the delete logic */
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int addrEphOpen = 0; /* Instruction to open the Ephermeral table */
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#ifndef SQLITE_OMIT_TRIGGER
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int isView; /* True if attempting to delete from a view */
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Trigger *pTrigger; /* List of table triggers, if required */
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@@ -295,11 +309,11 @@ void sqlite3DeleteFrom(
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}
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assert(!isView || pTrigger);
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/* Assign cursor number to the table and all its indices.
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/* Assign cursor numbers to the table and all its indices.
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*/
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assert( pTabList->nSrc==1 );
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iTabCur = pTabList->a[0].iCursor = pParse->nTab++;
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for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){
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for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){
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pParse->nTab++;
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}
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@@ -372,106 +386,129 @@ void sqlite3DeleteFrom(
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}
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}else
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#endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */
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if( !HasRowid(pTab) ){
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/* There is a WHERE clause on a WITHOUT ROWID table.
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*/
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Index *pPk; /* The PRIMARY KEY index on the table */
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int iPk; /* First of nPk memory cells holding PRIMARY KEY value */
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int iEph; /* Ephemeral table holding all primary key values */
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int iKey; /* Key value inserting into iEph */
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i16 nPk; /* Number of components of the PRIMARY KEY */
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pPk = sqlite3PrimaryKeyIndex(pTab);
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assert( pPk!=0 );
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nPk = pPk->nKeyCol;
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iPk = pParse->nMem+1;
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pParse->nMem += nPk;
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iKey = ++pParse->nMem;
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iEph = pParse->nTab++;
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sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEph, nPk);
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sqlite3VdbeSetP4KeyInfo(pParse, pPk);
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pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, 0, 0);
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if( pWInfo==0 ) goto delete_from_cleanup;
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for(i=0; i<nPk; i++){
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sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur, pPk->aiColumn[i],iPk+i);
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{
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if( HasRowid(pTab) ){
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/* For a rowid table, initialize the RowSet to an empty set */
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pPk = 0;
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nPk = 1;
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iRowSet = ++pParse->nMem;
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sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
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}else{
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/* For a WITHOUT ROWID table, create an ephermeral table used to
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** hold all primary keys for rows to be deleted. */
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pPk = sqlite3PrimaryKeyIndex(pTab);
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assert( pPk!=0 );
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nPk = pPk->nKeyCol;
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iPk = pParse->nMem+1;
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pParse->nMem += nPk;
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iEphCur = pParse->nTab++;
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addrEphOpen = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, iEphCur, nPk);
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sqlite3VdbeSetP4KeyInfo(pParse, pPk);
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}
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sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
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sqlite3IndexAffinityStr(v, pPk), P4_TRANSIENT);
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sqlite3VdbeAddOp2(v, OP_IdxInsert, iEph, iKey);
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/* Construct a query to find the rowid or primary key for every row
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** to be deleted, based on the WHERE clause.
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*/
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pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0,
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WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK,
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iTabCur+1);
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if( pWInfo==0 ) goto delete_from_cleanup;
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okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass);
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/* Keep track of the number of rows to be deleted */
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if( db->flags & SQLITE_CountRows ){
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sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
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}
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sqlite3WhereEnd(pWInfo);
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/* Open cursors for all indices of the table.
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*/
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sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite,
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iTabCur, &iDataCur, &iIdxCur);
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/* Loop over the primary keys to be deleted. */
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addr = sqlite3VdbeAddOp1(v, OP_Rewind, iEph);
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sqlite3VdbeAddOp2(v, OP_RowKey, iEph, iPk);
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/* Delete the row */
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sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
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iPk, 0, 1, OE_Default, 0);
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/* End of the delete loop */
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sqlite3VdbeAddOp2(v, OP_Next, iEph, addr+1);
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sqlite3VdbeJumpHere(v, addr);
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/* Close the cursors open on the table and its indexes. */
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assert( iDataCur>=iIdxCur );
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for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
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sqlite3VdbeAddOp1(v, OP_Close, iIdxCur+i);
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/* Extract the rowid or primary key for the current row */
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if( pPk ){
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for(i=0; i<nPk; i++){
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sqlite3ExprCodeGetColumnOfTable(v, pTab, iTabCur,
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pPk->aiColumn[i], iPk+i);
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}
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iKey = iPk;
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}else{
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iKey = pParse->nMem + 1;
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iKey = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iKey, 0);
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if( iKey>pParse->nMem ) pParse->nMem = iKey;
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}
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}else{
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/* There is a WHERE clause on a rowid table. Run a loop that extracts
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** all rowids to be deleted into a RowSet.
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*/
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int iRowSet = ++pParse->nMem; /* Register for rowset of rows to delete */
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int iRowid = ++pParse->nMem; /* Used for storing rowid values. */
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int regRowid; /* Actual register containing rowids */
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/* Collect rowids of every row to be deleted.
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*/
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sqlite3VdbeAddOp2(v, OP_Null, 0, iRowSet);
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pWInfo = sqlite3WhereBegin(
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pParse, pTabList, pWhere, 0, 0, WHERE_DUPLICATES_OK, 0
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);
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if( pWInfo==0 ) goto delete_from_cleanup;
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regRowid = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iTabCur, iRowid, 0);
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sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, regRowid);
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if( db->flags & SQLITE_CountRows ){
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sqlite3VdbeAddOp2(v, OP_AddImm, memCnt, 1);
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if( okOnePass ){
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/* For ONEPASS, no need to store the rowid/primary-key. There is only
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** one, so just keep it in its register(s) and fall through to the
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** delete code.
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*/
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nKey = nPk; /* OP_Found will use an unpacked key */
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aToOpen = sqlite3DbMallocRaw(db, nIdx+2);
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if( aToOpen==0 ){
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sqlite3WhereEnd(pWInfo);
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goto delete_from_cleanup;
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}
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memset(aToOpen, 1, nIdx+1);
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aToOpen[nIdx+1] = 0;
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if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0;
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if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0;
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if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen);
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addrDelete = sqlite3VdbeAddOp0(v, OP_Goto); /* Jump to DELETE logic */
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}else if( pPk ){
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/* Construct a composite key for the row to be deleted and remember it */
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iKey = ++pParse->nMem;
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nKey = 0; /* Zero tells OP_Found to use a composite key */
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sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey,
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sqlite3IndexAffinityStr(v, pPk), P4_TRANSIENT);
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sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey);
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}else{
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/* Get the rowid of the row to be deleted and remember it in the RowSet */
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nKey = 1; /* OP_Seek always uses a single rowid */
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sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey);
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}
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/* End of the WHERE loop */
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sqlite3WhereEnd(pWInfo);
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/* Delete every item whose key was written to the list during the
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** database scan. We have to delete items after the scan is complete
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** because deleting an item can change the scan order. */
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end = sqlite3VdbeMakeLabel(v);
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if( okOnePass ){
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/* Bypass the delete logic below if the WHERE loop found zero rows */
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addrBypass = sqlite3VdbeMakeLabel(v);
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sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBypass);
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sqlite3VdbeJumpHere(v, addrDelete);
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}
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/* Unless this is a view, open cursors for the table we are
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** deleting from and all its indices. If this is a view, then the
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** only effect this statement has is to fire the INSTEAD OF
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** triggers. */
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** triggers.
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*/
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if( !isView ){
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sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iTabCur,
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sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, iTabCur, aToOpen,
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&iDataCur, &iIdxCur);
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assert( iDataCur==iTabCur );
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assert( iIdxCur==iDataCur+1 );
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assert( pPk || iDataCur==iTabCur );
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assert( pPk || iIdxCur==iDataCur+1 );
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}
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addr = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, end, iRowid);
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/* Set up a loop over the rowids/primary-keys that were found in the
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** where-clause loop above.
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*/
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if( okOnePass ){
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/* Just one row. Hence the top-of-loop is a no-op */
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assert( nKey==nPk ); /* OP_Found will use an unpacked key */
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if( aToOpen[iDataCur-iTabCur] ){
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assert( pPk!=0 );
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sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey);
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}
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}else if( pPk ){
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addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur);
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sqlite3VdbeAddOp2(v, OP_RowKey, iEphCur, iKey);
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assert( nKey==0 ); /* OP_Found will use a composite key */
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}else{
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addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
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assert( nKey==1 );
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}
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/* Delete the row */
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#ifndef SQLITE_OMIT_VIRTUALTABLE
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if( IsVirtual(pTab) ){
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const char *pVTab = (const char *)sqlite3GetVTable(db, pTab);
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sqlite3VtabMakeWritable(pParse, pTab);
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sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iRowid, (char*)pVTab, P4_VTAB);
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sqlite3VdbeAddOp4(v, OP_VUpdate, 0, 1, iKey, pVTab, P4_VTAB);
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sqlite3VdbeChangeP5(v, OE_Abort);
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sqlite3MayAbort(pParse);
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}else
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@@ -479,21 +516,28 @@ void sqlite3DeleteFrom(
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{
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int count = (pParse->nested==0); /* True to count changes */
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sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur,
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iRowid, 1, count, OE_Default, 0);
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iKey, nKey, count, OE_Default, okOnePass);
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}
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/* End of the delete loop */
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sqlite3VdbeAddOp2(v, OP_Goto, 0, addr);
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sqlite3VdbeResolveLabel(v, end);
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/* End of the loop over all rowids/primary-keys. */
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if( okOnePass ){
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sqlite3VdbeResolveLabel(v, addrBypass);
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}else if( pPk ){
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sqlite3VdbeAddOp2(v, OP_Next, iEphCur, addrLoop+1);
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sqlite3VdbeJumpHere(v, addrLoop);
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}else{
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sqlite3VdbeAddOp2(v, OP_Goto, 0, addrLoop);
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sqlite3VdbeJumpHere(v, addrLoop);
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}
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/* Close the cursors open on the table and its indexes. */
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if( !isView && !IsVirtual(pTab) ){
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sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
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if( !pPk ) sqlite3VdbeAddOp1(v, OP_Close, iDataCur);
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for(i=0, pIdx=pTab->pIndex; pIdx; i++, pIdx=pIdx->pNext){
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sqlite3VdbeAddOp1(v, OP_Close, iIdxCur + i);
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}
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}
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}
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} /* End non-truncate path */
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/* Update the sqlite_sequence table by storing the content of the
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** maximum rowid counter values recorded while inserting into
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@@ -517,6 +561,7 @@ delete_from_cleanup:
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sqlite3AuthContextPop(&sContext);
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sqlite3SrcListDelete(db, pTabList);
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sqlite3ExprDelete(db, pWhere);
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sqlite3DbFree(db, aToOpen);
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return;
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}
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/* Make sure "isView" and other macros defined above are undefined. Otherwise
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@@ -583,6 +628,7 @@ void sqlite3GenerateRowDelete(
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if( sqlite3FkRequired(pParse, pTab, 0, 0) || pTrigger ){
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u32 mask; /* Mask of OLD.* columns in use */
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int iCol; /* Iterator used while populating OLD.* */
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int addrStart; /* Start of BEFORE trigger programs */
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/* TODO: Could use temporary registers here. Also could attempt to
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** avoid copying the contents of the rowid register. */
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@@ -603,15 +649,19 @@ void sqlite3GenerateRowDelete(
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}
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/* Invoke BEFORE DELETE trigger programs. */
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addrStart = sqlite3VdbeCurrentAddr(v);
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sqlite3CodeRowTrigger(pParse, pTrigger,
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TK_DELETE, 0, TRIGGER_BEFORE, pTab, iOld, onconf, iLabel
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);
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/* Seek the cursor to the row to be deleted again. It may be that
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** the BEFORE triggers coded above have already removed the row
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** being deleted. Do not attempt to delete the row a second time, and
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** do not fire AFTER triggers. */
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sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
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/* If any BEFORE triggers were coded, then seek the cursor to the
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** row to be deleted again. It may be that the BEFORE triggers moved
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** the cursor or of already deleted the row that the cursor was
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** pointing to.
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*/
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if( addrStart<sqlite3VdbeCurrentAddr(v) ){
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sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk);
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}
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/* Do FK processing. This call checks that any FK constraints that
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** refer to this table (i.e. constraints attached to other tables)
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