diff options
Diffstat (limited to 'lib/libsqlite3/src/delete.c')
| -rw-r--r-- | lib/libsqlite3/src/delete.c | 149 |
1 files changed, 101 insertions, 48 deletions
diff --git a/lib/libsqlite3/src/delete.c b/lib/libsqlite3/src/delete.c index 369cdaf6fe2..faef3a814e5 100644 --- a/lib/libsqlite3/src/delete.c +++ b/lib/libsqlite3/src/delete.c @@ -235,7 +235,7 @@ void sqlite3DeleteFrom( int iDb; /* Database number */ int memCnt = -1; /* Memory cell used for change counting */ int rcauth; /* Value returned by authorization callback */ - int okOnePass; /* True for one-pass algorithm without the FIFO */ + 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 */ @@ -247,12 +247,12 @@ void sqlite3DeleteFrom( 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 addrDelete = 0; /* Jump directly to the delete logic */ int addrEphOpen = 0; /* Instruction to open the Ephemeral table */ #ifndef SQLITE_OMIT_TRIGGER int isView; /* True if attempting to delete from a view */ Trigger *pTrigger; /* List of table triggers, if required */ + int bComplex; /* True if there are either triggers or FKs */ #endif memset(&sContext, 0, sizeof(sContext)); @@ -276,9 +276,11 @@ void sqlite3DeleteFrom( #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 +# define bComplex 0 #endif #ifdef SQLITE_OMIT_VIEW # undef isView @@ -359,8 +361,10 @@ void sqlite3DeleteFrom( ** 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) + if( rcauth==SQLITE_OK + && pWhere==0 + && !bComplex + && !IsVirtual(pTab) ){ assert( !isView ); sqlite3TableLock(pParse, iDb, pTab->tnum, 1, pTab->zName); @@ -375,6 +379,8 @@ void sqlite3DeleteFrom( }else #endif /* SQLITE_OMIT_TRUNCATE_OPTIMIZATION */ { + u16 wcf = WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK; + wcf |= (bComplex ? 0 : WHERE_ONEPASS_MULTIROW); if( HasRowid(pTab) ){ /* For a rowid table, initialize the RowSet to an empty set */ pPk = 0; @@ -395,13 +401,18 @@ void sqlite3DeleteFrom( } /* Construct a query to find the rowid or primary key for every row - ** to be deleted, based on the WHERE clause. + ** 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, - WHERE_ONEPASS_DESIRED|WHERE_DUPLICATES_OK, - iTabCur+1); + pWInfo = sqlite3WhereBegin(pParse, pTabList, pWhere, 0, 0, wcf, iTabCur+1); if( pWInfo==0 ) goto delete_from_cleanup; - okOnePass = sqlite3WhereOkOnePass(pWInfo, aiCurOnePass); + 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 ){ @@ -411,6 +422,7 @@ void sqlite3DeleteFrom( /* 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); } @@ -421,11 +433,10 @@ void sqlite3DeleteFrom( if( iKey>pParse->nMem ) pParse->nMem = iKey; } - if( okOnePass ){ - /* For ONEPASS, no need to store the rowid/primary-key. There is only + 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. - */ + ** delete code. */ nKey = nPk; /* OP_Found will use an unpacked key */ aToOpen = sqlite3DbMallocRaw(db, nIdx+2); if( aToOpen==0 ){ @@ -437,27 +448,27 @@ void sqlite3DeleteFrom( if( aiCurOnePass[0]>=0 ) aToOpen[aiCurOnePass[0]-iTabCur] = 0; if( aiCurOnePass[1]>=0 ) aToOpen[aiCurOnePass[1]-iTabCur] = 0; if( addrEphOpen ) sqlite3VdbeChangeToNoop(v, addrEphOpen); - addrDelete = sqlite3VdbeAddOp0(v, OP_Goto); /* Jump to DELETE logic */ - }else if( pPk ){ - /* Construct a composite key for the row to be deleted and remember it */ - iKey = ++pParse->nMem; - nKey = 0; /* Zero tells OP_Found to use a composite key */ - sqlite3VdbeAddOp4(v, OP_MakeRecord, iPk, nPk, iKey, - sqlite3IndexAffinityStr(v, pPk), nPk); - sqlite3VdbeAddOp2(v, OP_IdxInsert, iEphCur, iKey); }else{ - /* Get the rowid of the row to be deleted and remember it in the RowSet */ - nKey = 1; /* OP_Seek always uses a single rowid */ - sqlite3VdbeAddOp2(v, OP_RowSetAdd, iRowSet, iKey); + 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); + } } - /* End of the WHERE loop */ - sqlite3WhereEnd(pWInfo); - if( okOnePass ){ - /* Bypass the delete logic below if the WHERE loop found zero rows */ + /* If this DELETE cannot use the ONEPASS strategy, this is the + ** end of the WHERE loop */ + if( eOnePass!=ONEPASS_OFF ){ addrBypass = sqlite3VdbeMakeLabel(v); - sqlite3VdbeAddOp2(v, OP_Goto, 0, addrBypass); - sqlite3VdbeJumpHere(v, addrDelete); + }else{ + sqlite3WhereEnd(pWInfo); } /* Unless this is a view, open cursors for the table we are @@ -466,21 +477,24 @@ void sqlite3DeleteFrom( ** triggers. */ if( !isView ){ + int iAddrOnce = 0; + if( eOnePass==ONEPASS_MULTI ){ + iAddrOnce = sqlite3CodeOnce(pParse); VdbeCoverage(v); + } testcase( IsVirtual(pTab) ); sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 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( okOnePass ){ - /* Just one row. Hence the top-of-loop is a no-op */ + if( eOnePass!=ONEPASS_OFF ){ assert( nKey==nPk ); /* OP_Found will use an unpacked key */ - assert( !IsVirtual(pTab) ); - if( aToOpen[iDataCur-iTabCur] ){ + if( !IsVirtual(pTab) && aToOpen[iDataCur-iTabCur] ){ assert( pPk!=0 || pTab->pSelect!=0 ); sqlite3VdbeAddOp4Int(v, OP_NotFound, iDataCur, addrBypass, iKey, nKey); VdbeCoverage(v); @@ -502,23 +516,32 @@ void sqlite3DeleteFrom( 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, okOnePass); + iKey, nKey, count, OE_Default, eOnePass, iIdxNoSeek); } /* End of the loop over all rowids/primary-keys. */ - if( okOnePass ){ + 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{ - sqlite3VdbeAddOp2(v, OP_Goto, 0, addrLoop); + sqlite3VdbeGoto(v, addrLoop); sqlite3VdbeJumpHere(v, addrLoop); } @@ -585,6 +608,25 @@ delete_from_cleanup: ** sequence of nPk memory cells starting at iPk. If nPk==0 that means ** that a search record formed from OP_MakeRecord is contained in the ** single memory location iPk. +** +** eMode: +** Parameter eMode may be passed either ONEPASS_OFF (0), ONEPASS_SINGLE, or +** ONEPASS_MULTI. If eMode is not ONEPASS_OFF, then the cursor +** iDataCur already points to the row to delete. If eMode is ONEPASS_OFF +** then this function must seek iDataCur to the entry identified by iPk +** and nPk before reading from it. +** +** If eMode is ONEPASS_MULTI, then this call is being made as part +** of a ONEPASS delete that affects multiple rows. In this case, if +** iIdxNoSeek is a valid cursor number (>=0), then its position should +** be preserved following the delete operation. Or, if iIdxNoSeek is not +** a valid cursor number, the position of iDataCur should be preserved +** instead. +** +** iIdxNoSeek: +** If iIdxNoSeek is a valid cursor number (>=0), then it identifies an +** index cursor (from within array of cursors starting at iIdxCur) that +** already points to the index entry to be deleted. */ void sqlite3GenerateRowDelete( Parse *pParse, /* Parsing context */ @@ -596,7 +638,8 @@ void sqlite3GenerateRowDelete( i16 nPk, /* Number of PRIMARY KEY memory cells */ u8 count, /* If non-zero, increment the row change counter */ u8 onconf, /* Default ON CONFLICT policy for triggers */ - u8 bNoSeek /* iDataCur is already pointing to the row to delete */ + u8 eMode, /* ONEPASS_OFF, _SINGLE, or _MULTI. See above */ + int iIdxNoSeek /* Cursor number of cursor that does not need seeking */ ){ Vdbe *v = pParse->pVdbe; /* Vdbe */ int iOld = 0; /* First register in OLD.* array */ @@ -613,7 +656,7 @@ void sqlite3GenerateRowDelete( ** not attempt to delete it or fire any DELETE triggers. */ iLabel = sqlite3VdbeMakeLabel(v); opSeek = HasRowid(pTab) ? OP_NotExists : OP_NotFound; - if( !bNoSeek ){ + if( eMode==ONEPASS_OFF ){ sqlite3VdbeAddOp4Int(v, opSeek, iDataCur, iLabel, iPk, nPk); VdbeCoverageIf(v, opSeek==OP_NotExists); VdbeCoverageIf(v, opSeek==OP_NotFound); @@ -673,11 +716,15 @@ void sqlite3GenerateRowDelete( ** 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, iDataCur, iIdxCur, 0); + sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,iIdxNoSeek); sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, (count?OPFLAG_NCHANGE:0)); if( count ){ sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT); } + if( iIdxNoSeek>=0 ){ + sqlite3VdbeAddOp1(v, OP_Delete, iIdxNoSeek); + } + sqlite3VdbeChangeP5(v, eMode==ONEPASS_MULTI); } /* Do any ON CASCADE, SET NULL or SET DEFAULT operations required to @@ -720,7 +767,8 @@ void sqlite3GenerateRowIndexDelete( 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 *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 */ @@ -736,11 +784,12 @@ void sqlite3GenerateRowIndexDelete( 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); + &iPartIdxLabel, pPrior, r1); sqlite3VdbeAddOp3(v, OP_IdxDelete, iIdxCur+i, r1, - pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn); + pIdx->uniqNotNull ? pIdx->nKeyCol : pIdx->nColumn); sqlite3ResolvePartIdxLabel(pParse, iPartIdxLabel); pPrior = pIdx; } @@ -789,14 +838,13 @@ int sqlite3GenerateIndexKey( ){ Vdbe *v = pParse->pVdbe; int j; - Table *pTab = pIdx->pTable; int regBase; int nCol; if( piPartIdxLabel ){ if( pIdx->pPartIdxWhere ){ *piPartIdxLabel = sqlite3VdbeMakeLabel(v); - pParse->iPartIdxTab = iDataCur; + pParse->iSelfTab = iDataCur; sqlite3ExprCachePush(pParse); sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, *piPartIdxLabel, SQLITE_JUMPIFNULL); @@ -808,9 +856,14 @@ int sqlite3GenerateIndexKey( 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] ) continue; - sqlite3ExprCodeGetColumnOfTable(v, pTab, iDataCur, pIdx->aiColumn[j], - regBase+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. |