diff options
Diffstat (limited to 'src/whereexpr.c')
| -rw-r--r-- | src/whereexpr.c | 35 |
1 files changed, 23 insertions, 12 deletions
diff --git a/src/whereexpr.c b/src/whereexpr.c index 4a24dadd2..6dcbd0167 100644 --- a/src/whereexpr.c +++ b/src/whereexpr.c @@ -931,30 +931,38 @@ static void exprAnalyzeOrTerm( ** 1. The SQLITE_Transitive optimization must be enabled ** 2. Must be either an == or an IS operator ** 3. Not originating in the ON clause of an OUTER JOIN -** 4. The affinities of A and B must be compatible -** 5a. Both operands use the same collating sequence OR -** 5b. The overall collating sequence is BINARY +** 4. The operator is not IS or else the query does not contain RIGHT JOIN +** 5. The affinities of A and B must be compatible +** 6a. Both operands use the same collating sequence OR +** 6b. The overall collating sequence is BINARY ** If this routine returns TRUE, that means that the RHS can be substituted ** for the LHS anyplace else in the WHERE clause where the LHS column occurs. ** This is an optimization. No harm comes from returning 0. But if 1 is ** returned when it should not be, then incorrect answers might result. */ -static int termIsEquivalence(Parse *pParse, Expr *pExpr){ +static int termIsEquivalence(Parse *pParse, Expr *pExpr, SrcList *pSrc){ char aff1, aff2; CollSeq *pColl; - if( !OptimizationEnabled(pParse->db, SQLITE_Transitive) ) return 0; - if( pExpr->op!=TK_EQ && pExpr->op!=TK_IS ) return 0; - if( ExprHasProperty(pExpr, EP_OuterON) ) return 0; + if( !OptimizationEnabled(pParse->db, SQLITE_Transitive) ) return 0; /* (1) */ + if( pExpr->op!=TK_EQ && pExpr->op!=TK_IS ) return 0; /* (2) */ + if( ExprHasProperty(pExpr, EP_OuterON) ) return 0; /* (3) */ + if( pExpr->op==TK_IS && (pSrc->a[0].fg.jointype & JT_LTORJ)!=0 ){ + return 0; /* (4) */ + } aff1 = sqlite3ExprAffinity(pExpr->pLeft); aff2 = sqlite3ExprAffinity(pExpr->pRight); if( aff1!=aff2 && (!sqlite3IsNumericAffinity(aff1) || !sqlite3IsNumericAffinity(aff2)) ){ - return 0; + return 0; /* (5) */ } pColl = sqlite3ExprCompareCollSeq(pParse, pExpr); - if( sqlite3IsBinary(pColl) ) return 1; - return sqlite3ExprCollSeqMatch(pParse, pExpr->pLeft, pExpr->pRight); + if( !sqlite3IsBinary(pColl) + && !sqlite3ExprCollSeqMatch(pParse, pExpr->pLeft, pExpr->pRight) + ){ + return 0; /* (6) */ + } + return 1; } /* @@ -1112,6 +1120,9 @@ static void exprAnalyze( } assert( pWC->nTerm > idxTerm ); pTerm = &pWC->a[idxTerm]; +#ifdef SQLITE_DEBUG + pTerm->iTerm = idxTerm; +#endif pMaskSet = &pWInfo->sMaskSet; pExpr = pTerm->pExpr; assert( pExpr!=0 ); /* Because malloc() has not failed */ @@ -1219,8 +1230,8 @@ static void exprAnalyze( if( op==TK_IS ) pNew->wtFlags |= TERM_IS; pTerm = &pWC->a[idxTerm]; pTerm->wtFlags |= TERM_COPIED; - - if( termIsEquivalence(pParse, pDup) ){ + assert( pWInfo->pTabList!=0 ); + if( termIsEquivalence(pParse, pDup, pWInfo->pTabList) ){ pTerm->eOperator |= WO_EQUIV; eExtraOp = WO_EQUIV; } |