From 100faa2b25e79269b60b0c61f8d58679600b9443 Mon Sep 17 00:00:00 2001 From: "D. Richard Hipp" Date: Thu, 28 Sep 2017 01:58:23 +0000 Subject: [PATCH] Add new routines to simplify dealing with collating sequences in expressions: sqlite3ExprNNCollSeq() and sqlite3ExprCollSeqMatch(). --- src/expr.c | 35 +++++++++++++++++++++++++++++++++-- src/select.c | 5 +---- src/sqliteInt.h | 2 ++ src/where.c | 19 +++++++------------ src/whereexpr.c | 7 +------ 5 files changed, 44 insertions(+), 24 deletions(-) diff --git a/src/expr.c b/src/expr.c index b482fafc05..8282c99a4a 100644 --- a/src/expr.c +++ b/src/expr.c @@ -124,6 +124,11 @@ Expr *sqlite3ExprSkipCollate(Expr *pExpr){ ** Return the collation sequence for the expression pExpr. If ** there is no defined collating sequence, return NULL. ** +** See also: sqlite3ExprNNCollSeq() +** +** The sqlite3ExprNNCollSeq() works the same exact that it returns the +** default collation if pExpr has no defined collation. +** ** The collating sequence might be determined by a COLLATE operator ** or by the presence of a column with a defined collating sequence. ** COLLATE operators take first precedence. Left operands take @@ -189,6 +194,32 @@ CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){ } /* +** Return the collation sequence for the expression pExpr. If +** there is no defined collating sequence, return a pointer to the +** defautl collation sequence. +** +** See also: sqlite3ExprCollSeq() +** +** The sqlite3ExprCollSeq() routine works the same except that it +** returns NULL if there is no defined collation. +*/ +CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr){ + CollSeq *p = sqlite3ExprCollSeq(pParse, pExpr); + if( p==0 ) p = pParse->db->pDfltColl; + assert( p!=0 ); + return p; +} + +/* +** Return TRUE if the two expressions have equivalent collating sequences. +*/ +int sqlite3ExprCollSeqMatch(Parse *pParse, Expr *pE1, Expr *pE2){ + CollSeq *pColl1 = sqlite3ExprNNCollSeq(pParse, pE1); + CollSeq *pColl2 = sqlite3ExprNNCollSeq(pParse, pE2); + return sqlite3StrICmp(pColl1->zName, pColl2->zName)==0; +} + +/* ** pExpr is an operand of a comparison operator. aff2 is the ** type affinity of the other operand. This routine returns the ** type affinity that should be used for the comparison operator. @@ -1843,8 +1874,8 @@ static int exprNodeIsConstantOrGroupBy(Walker *pWalker, Expr *pExpr){ for(i=0; inExpr; i++){ Expr *p = pGroupBy->a[i].pExpr; if( sqlite3ExprCompare(0, pExpr, p, -1)<2 ){ - CollSeq *pColl = sqlite3ExprCollSeq(pWalker->pParse, p); - if( pColl==0 || sqlite3_stricmp("BINARY", pColl->zName)==0 ){ + CollSeq *pColl = sqlite3ExprNNCollSeq(pWalker->pParse, p); + if( sqlite3_stricmp("BINARY", pColl->zName)==0 ){ return WRC_Prune; } } diff --git a/src/select.c b/src/select.c index 971e7f5d4e..79abda90a3 100644 --- a/src/select.c +++ b/src/select.c @@ -1109,10 +1109,7 @@ static KeyInfo *keyInfoFromExprList( if( pInfo ){ assert( sqlite3KeyInfoIsWriteable(pInfo) ); for(i=iStart, pItem=pList->a+iStart; ipExpr); - if( !pColl ) pColl = db->pDfltColl; - pInfo->aColl[i-iStart] = pColl; + pInfo->aColl[i-iStart] = sqlite3ExprNNCollSeq(pParse, pItem->pExpr); pInfo->aSortOrder[i-iStart] = pItem->sortOrder; } } diff --git a/src/sqliteInt.h b/src/sqliteInt.h index 14514007c4..3259df894f 100644 --- a/src/sqliteInt.h +++ b/src/sqliteInt.h @@ -4004,6 +4004,8 @@ int sqlite3ReadSchema(Parse *pParse); CollSeq *sqlite3FindCollSeq(sqlite3*,u8 enc, const char*,int); CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char*zName); CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr); +CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr); +int sqlite3ExprCollSeqMatch(Parse*,Expr*,Expr*); Expr *sqlite3ExprAddCollateToken(Parse *pParse, Expr*, const Token*, int); Expr *sqlite3ExprAddCollateString(Parse*,Expr*,const char*); Expr *sqlite3ExprSkipCollate(Expr*); diff --git a/src/where.c b/src/where.c index a02923c991..5a3d44f9ee 100644 --- a/src/where.c +++ b/src/where.c @@ -403,8 +403,8 @@ static int findIndexCol( && p->iColumn==pIdx->aiColumn[iCol] && p->iTable==iBase ){ - CollSeq *pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr); - if( pColl && 0==sqlite3StrICmp(pColl->zName, zColl) ){ + CollSeq *pColl = sqlite3ExprNNCollSeq(pParse, pList->a[i].pExpr); + if( 0==sqlite3StrICmp(pColl->zName, zColl) ){ return i; } } @@ -3579,14 +3579,10 @@ static i8 wherePathSatisfiesOrderBy( if( j>=pLoop->nLTerm ) continue; } if( (pTerm->eOperator&(WO_EQ|WO_IS))!=0 && pOBExpr->iColumn>=0 ){ - const char *z1, *z2; - pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr); - if( !pColl ) pColl = db->pDfltColl; - z1 = pColl->zName; - pColl = sqlite3ExprCollSeq(pWInfo->pParse, pTerm->pExpr); - if( !pColl ) pColl = db->pDfltColl; - z2 = pColl->zName; - if( sqlite3StrICmp(z1, z2)!=0 ) continue; + if( sqlite3ExprCollSeqMatch(pWInfo->pParse, + pOrderBy->a[i].pExpr, pTerm->pExpr)==0 ){ + continue; + } testcase( pTerm->pExpr->op==TK_IS ); } obSat |= MASKBIT(i); @@ -3696,8 +3692,7 @@ static i8 wherePathSatisfiesOrderBy( } } if( iColumn!=XN_ROWID ){ - pColl = sqlite3ExprCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr); - if( !pColl ) pColl = db->pDfltColl; + pColl = sqlite3ExprNNCollSeq(pWInfo->pParse, pOrderBy->a[i].pExpr); if( sqlite3StrICmp(pColl->zName, pIndex->azColl[j])!=0 ) continue; } pLoop->u.btree.nIdxCol = j+1; diff --git a/src/whereexpr.c b/src/whereexpr.c index da07f56ce8..9f83a84534 100644 --- a/src/whereexpr.c +++ b/src/whereexpr.c @@ -842,7 +842,6 @@ static void exprAnalyzeOrTerm( static int termIsEquivalence(Parse *pParse, Expr *pExpr){ char aff1, aff2; CollSeq *pColl; - const char *zColl1, *zColl2; if( !OptimizationEnabled(pParse->db, SQLITE_Transitive) ) return 0; if( pExpr->op!=TK_EQ && pExpr->op!=TK_IS ) return 0; if( ExprHasProperty(pExpr, EP_FromJoin) ) return 0; @@ -855,11 +854,7 @@ static int termIsEquivalence(Parse *pParse, Expr *pExpr){ } pColl = sqlite3BinaryCompareCollSeq(pParse, pExpr->pLeft, pExpr->pRight); if( pColl==0 || sqlite3StrICmp(pColl->zName, "BINARY")==0 ) return 1; - pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft); - zColl1 = pColl ? pColl->zName : 0; - pColl = sqlite3ExprCollSeq(pParse, pExpr->pRight); - zColl2 = pColl ? pColl->zName : 0; - return sqlite3_stricmp(zColl1, zColl2)==0; + return sqlite3ExprCollSeqMatch(pParse, pExpr->pLeft, pExpr->pRight); } /* -- 2.11.4.GIT