diff options
Diffstat (limited to 'src/where.c')
| -rw-r--r-- | src/where.c | 109 |
1 files changed, 91 insertions, 18 deletions
diff --git a/src/where.c b/src/where.c index b9385a5ec..25c1c0414 100644 --- a/src/where.c +++ b/src/where.c @@ -2722,7 +2722,7 @@ static void explainOneScan( Index *pIdx = pLoop->u.btree.pIndex; char *zWhere = explainIndexRange(db, pLoop, pItem->pTab); assert( !(flags&WHERE_AUTO_INDEX) || (flags&WHERE_IDX_ONLY) ); - if( !HasRowid(pItem->pTab) && pIdx->autoIndex==2 ){ + if( !HasRowid(pItem->pTab) && IsPrimaryKeyIndex(pIdx) ){ zFmt = zWhere ? "%s USING PRIMARY KEY%.0s%s" : "%s%.0s%s"; }else if( flags & WHERE_AUTO_INDEX ){ zFmt = "%s USING AUTOMATIC COVERING INDEX%.0s%s"; @@ -3223,7 +3223,7 @@ static Bitmask codeOneLoopStart( sqlite3VdbeAddOp2(v, OP_IdxRowid, iIdxCur, iRowidReg); sqlite3ExprCacheStore(pParse, iCur, -1, iRowidReg); sqlite3VdbeAddOp2(v, OP_Seek, iCur, iRowidReg); /* Deferred seek */ - }else{ + }else if( iCur!=iIdxCur ){ Index *pPk = sqlite3PrimaryKeyIndex(pIdx->pTable); iRowidReg = sqlite3GetTempRange(pParse, pPk->nKeyCol); for(j=0; j<pPk->nKeyCol; j++){ @@ -3293,6 +3293,10 @@ static Bitmask codeOneLoopStart( ** ** B: <after the loop> ** + ** Added 2014-05-26: If the table is a WITHOUT ROWID table, then + ** use an ephermeral index instead of a RowSet to record the primary + ** keys of the rows we have already seen. + ** */ WhereClause *pOrWc; /* The OR-clause broken out into subterms */ SrcList *pOrTab; /* Shortened table list or OR-clause generation */ @@ -3307,6 +3311,7 @@ static Bitmask codeOneLoopStart( int untestedTerms = 0; /* Some terms not completely tested */ int ii; /* Loop counter */ Expr *pAndExpr = 0; /* An ".. AND (...)" expression */ + Table *pTab = pTabItem->pTab; pTerm = pLoop->aLTerm[0]; assert( pTerm!=0 ); @@ -3339,7 +3344,8 @@ static Bitmask codeOneLoopStart( } /* Initialize the rowset register to contain NULL. An SQL NULL is - ** equivalent to an empty rowset. + ** equivalent to an empty rowset. Or, create an ephermeral index + ** capable of holding primary keys in the case of a WITHOUT ROWID. ** ** Also initialize regReturn to contain the address of the instruction ** immediately following the OP_Return at the bottom of the loop. This @@ -3350,9 +3356,16 @@ static Bitmask codeOneLoopStart( ** called on an uninitialized cursor. */ if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){ - regRowset = ++pParse->nMem; + if( HasRowid(pTab) ){ + regRowset = ++pParse->nMem; + sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset); + }else{ + Index *pPk = sqlite3PrimaryKeyIndex(pTab); + regRowset = pParse->nTab++; + sqlite3VdbeAddOp2(v, OP_OpenEphemeral, regRowset, pPk->nKeyCol); + sqlite3VdbeSetP4KeyInfo(pParse, pPk); + } regRowid = ++pParse->nMem; - sqlite3VdbeAddOp2(v, OP_Null, 0, regRowset); } iRetInit = sqlite3VdbeAddOp2(v, OP_Integer, 0, regReturn); @@ -3388,11 +3401,16 @@ static Bitmask codeOneLoopStart( } } + /* Run a separate WHERE clause for each term of the OR clause. After + ** eliminating duplicates from other WHERE clauses, the action for each + ** sub-WHERE clause is to to invoke the main loop body as a subroutine. + */ for(ii=0; ii<pOrWc->nTerm; ii++){ WhereTerm *pOrTerm = &pOrWc->a[ii]; if( pOrTerm->leftCursor==iCur || (pOrTerm->eOperator & WO_AND)!=0 ){ - WhereInfo *pSubWInfo; /* Info for single OR-term scan */ - Expr *pOrExpr = pOrTerm->pExpr; + WhereInfo *pSubWInfo; /* Info for single OR-term scan */ + Expr *pOrExpr = pOrTerm->pExpr; /* Current OR clause term */ + int j1 = 0; /* Address of jump operation */ if( pAndExpr && !ExprHasProperty(pOrExpr, EP_FromJoin) ){ pAndExpr->pLeft = pOrExpr; pOrExpr = pAndExpr; @@ -3407,17 +3425,63 @@ static Bitmask codeOneLoopStart( explainOneScan( pParse, pOrTab, &pSubWInfo->a[0], iLevel, pLevel->iFrom, 0 ); + /* This is the sub-WHERE clause body. First skip over + ** duplicate rows from prior sub-WHERE clauses, and record the + ** rowid (or PRIMARY KEY) for the current row so that the same + ** row will be skipped in subsequent sub-WHERE clauses. + */ if( (pWInfo->wctrlFlags & WHERE_DUPLICATES_OK)==0 ){ - int iSet = ((ii==pOrWc->nTerm-1)?-1:ii); int r; - r = sqlite3ExprCodeGetColumn(pParse, pTabItem->pTab, -1, iCur, - regRowid, 0); - sqlite3VdbeAddOp4Int(v, OP_RowSetTest, regRowset, - sqlite3VdbeCurrentAddr(v)+2, r, iSet); - VdbeCoverage(v); + int iSet = ((ii==pOrWc->nTerm-1)?-1:ii); + if( HasRowid(pTab) ){ + r = sqlite3ExprCodeGetColumn(pParse, pTab, -1, iCur, regRowid, 0); + j1 = sqlite3VdbeAddOp4Int(v, OP_RowSetTest, regRowset, 0, r,iSet); + VdbeCoverage(v); + }else{ + Index *pPk = sqlite3PrimaryKeyIndex(pTab); + int nPk = pPk->nKeyCol; + int iPk; + + /* Read the PK into an array of temp registers. */ + r = sqlite3GetTempRange(pParse, nPk); + for(iPk=0; iPk<nPk; iPk++){ + int iCol = pPk->aiColumn[iPk]; + sqlite3ExprCodeGetColumn(pParse, pTab, iCol, iCur, r+iPk, 0); + } + + /* Check if the temp table already contains this key. If so, + ** the row has already been included in the result set and + ** can be ignored (by jumping past the Gosub below). Otherwise, + ** insert the key into the temp table and proceed with processing + ** the row. + ** + ** Use some of the same optimizations as OP_RowSetTest: If iSet + ** is zero, assume that the key cannot already be present in + ** the temp table. And if iSet is -1, assume that there is no + ** need to insert the key into the temp table, as it will never + ** be tested for. */ + if( iSet ){ + j1 = sqlite3VdbeAddOp4Int(v, OP_Found, regRowset, 0, r, nPk); + VdbeCoverage(v); + } + if( iSet>=0 ){ + sqlite3VdbeAddOp3(v, OP_MakeRecord, r, nPk, regRowid); + sqlite3VdbeAddOp3(v, OP_IdxInsert, regRowset, regRowid, 0); + if( iSet ) sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT); + } + + /* Release the array of temp registers */ + sqlite3ReleaseTempRange(pParse, r, nPk); + } } + + /* Invoke the main loop body as a subroutine */ sqlite3VdbeAddOp2(v, OP_Gosub, regReturn, iLoopBody); + /* Jump here (skipping the main loop body subroutine) if the + ** current sub-WHERE row is a duplicate from prior sub-WHEREs. */ + if( j1 ) sqlite3VdbeJumpHere(v, j1); + /* The pSubWInfo->untestedTerms flag means that this OR term ** contained one or more AND term from a notReady table. The ** terms from the notReady table could not be tested and will @@ -3441,6 +3505,7 @@ static Bitmask codeOneLoopStart( assert( (pSubLoop->wsFlags & WHERE_AUTO_INDEX)==0 ); if( (pSubLoop->wsFlags & WHERE_INDEXED)!=0 && (ii==0 || pSubLoop->u.btree.pIndex==pCov) + && (HasRowid(pTab) || !IsPrimaryKeyIndex(pSubLoop->u.btree.pIndex)) ){ assert( pSubWInfo->a[0].iIdxCur==iCovCur ); pCov = pSubLoop->u.btree.pIndex; @@ -4766,7 +4831,6 @@ static int whereLoopAddOr(WhereLoopBuilder *pBuilder, Bitmask mExtra){ pNew = pBuilder->pNew; memset(&sSum, 0, sizeof(sSum)); pItem = pWInfo->pTabList->a + pNew->iTab; - if( !HasRowid(pItem->pTab) ) return SQLITE_OK; iCur = pItem->iCursor; for(pTerm=pWC->a; pTerm<pWCEnd && rc==SQLITE_OK; pTerm++){ @@ -6015,7 +6079,14 @@ WhereInfo *sqlite3WhereBegin( int op = OP_OpenRead; /* iIdxCur is always set if to a positive value if ONEPASS is possible */ assert( iIdxCur!=0 || (pWInfo->wctrlFlags & WHERE_ONEPASS_DESIRED)==0 ); - if( pWInfo->okOnePass ){ + if( !HasRowid(pTab) && IsPrimaryKeyIndex(pIx) + && (wctrlFlags & WHERE_ONETABLE_ONLY)!=0 + ){ + /* This is one term of an OR-optimization using the PRIMARY KEY of a + ** WITHOUT ROWID table. No need for a separate index */ + iIndexCur = pLevel->iTabCur; + op = 0; + }else if( pWInfo->okOnePass ){ Index *pJ = pTabItem->pTab->pIndex; iIndexCur = iIdxCur; assert( wctrlFlags & WHERE_ONEPASS_DESIRED ); @@ -6033,9 +6104,11 @@ WhereInfo *sqlite3WhereBegin( pLevel->iIdxCur = iIndexCur; assert( pIx->pSchema==pTab->pSchema ); assert( iIndexCur>=0 ); - sqlite3VdbeAddOp3(v, op, iIndexCur, pIx->tnum, iDb); - sqlite3VdbeSetP4KeyInfo(pParse, pIx); - VdbeComment((v, "%s", pIx->zName)); + if( op ){ + sqlite3VdbeAddOp3(v, op, iIndexCur, pIx->tnum, iDb); + sqlite3VdbeSetP4KeyInfo(pParse, pIx); + VdbeComment((v, "%s", pIx->zName)); + } } if( iDb>=0 ) sqlite3CodeVerifySchema(pParse, iDb); notReady &= ~getMask(&pWInfo->sMaskSet, pTabItem->iCursor); |