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Fix the LIKE optimization even when comparing mixed-case BLOBs.

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FossilOrigin-Name: a58aafdb4e1422b6a8ffc07a67984928bbedf919
This commit is contained in:
drh
2015-03-06 19:47:38 +00:00
parent f07cf6e2a5
commit 8f1a7ed33f
4 changed files with 61 additions and 24 deletions
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62
src/where.c
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@@ -1264,9 +1264,25 @@ static void exprAnalyze(
int idxNew1;
int idxNew2;
Token sCollSeqName; /* Name of collating sequence */
const u16 wtFlags = TERM_LIKEOPT | TERM_VIRTUAL | TERM_DYNAMIC;
pTerm->wtFlags |= TERM_LIKE;
pLeft = pExpr->x.pList->a[1].pExpr;
pStr2 = sqlite3ExprDup(db, pStr1, 0);
/* Convert the lower bound to upper-case and the upper bound to
** lower-case (upper-case is less than lower-case in ASCII) so that
** the range constraints also work for BLOBs
*/
if( noCase && !pParse->db->mallocFailed ){
int i;
char c;
for(i=0; (c = pStr1->u.zToken[i])!=0; i++){
pStr1->u.zToken[i] = sqlite3Toupper(c);
pStr2->u.zToken[i] = sqlite3Tolower(c);
}
}
if( !db->mallocFailed ){
u8 c, *pC; /* Last character before the first wildcard */
pC = (u8*)&pStr2->u.zToken[sqlite3Strlen30(pStr2->u.zToken)-1];
@@ -1286,12 +1302,11 @@ static void exprAnalyze(
sCollSeqName.z = noCase ? "NOCASE" : "BINARY";
sCollSeqName.n = 6;
pNewExpr1 = sqlite3ExprDup(db, pLeft, 0);
pNewExpr1 = sqlite3PExpr(pParse, TK_GE,
pNewExpr1 = sqlite3PExpr(pParse, TK_GE,
sqlite3ExprAddCollateToken(pParse,pNewExpr1,&sCollSeqName),
pStr1, 0);
transferJoinMarkings(pNewExpr1, pExpr);
idxNew1 = whereClauseInsert(pWC, pNewExpr1,
TERM_LIKEOPT|TERM_VIRTUAL|TERM_DYNAMIC);
idxNew1 = whereClauseInsert(pWC, pNewExpr1, wtFlags);
testcase( idxNew1==0 );
exprAnalyze(pSrc, pWC, idxNew1);
pNewExpr2 = sqlite3ExprDup(db, pLeft, 0);
@@ -1299,8 +1314,7 @@ static void exprAnalyze(
sqlite3ExprAddCollateToken(pParse,pNewExpr2,&sCollSeqName),
pStr2, 0);
transferJoinMarkings(pNewExpr2, pExpr);
idxNew2 = whereClauseInsert(pWC, pNewExpr2,
TERM_LIKEOPT|TERM_VIRTUAL|TERM_DYNAMIC);
idxNew2 = whereClauseInsert(pWC, pNewExpr2, wtFlags);
testcase( idxNew2==0 );
exprAnalyze(pSrc, pWC, idxNew2);
pTerm = &pWC->a[idxTerm];
@@ -2475,20 +2489,37 @@ static int whereInScanEst(
** but joins might run a little slower. The trick is to disable as much
** as we can without disabling too much. If we disabled in (1), we'd get
** the wrong answer. See ticket #813.
**
** If all the children of a term are disabled, then that term is also
** automatically disabled. In this way, terms get disabled if derived
** virtual terms are tested first. For example:
**
** x GLOB 'abc*' AND x>='abc' AND x<'acd'
** \___________/ \______/ \_____/
** parent child1 child2
**
** Only the parent term was in the original WHERE clause. The child1
** and child2 terms were added by the LIKE optimization. If both of
** the virtual child terms are valid, then testing of the parent can be
** skipped.
*/
static void disableTerm(WhereLevel *pLevel, WhereTerm *pTerm){
if( pTerm
int nLoop = 0;
while( pTerm
&& (pTerm->wtFlags & TERM_CODED)==0
&& (pLevel->iLeftJoin==0 || ExprHasProperty(pTerm->pExpr, EP_FromJoin))
&& (pLevel->notReady & pTerm->prereqAll)==0
){
pTerm->wtFlags |= TERM_CODED;
if( pTerm->iParent>=0 ){
WhereTerm *pOther = &pTerm->pWC->a[pTerm->iParent];
if( (--pOther->nChild)==0 ){
disableTerm(pLevel, pOther);
}
if( nLoop && (pTerm->wtFlags & TERM_LIKE)!=0 ){
pTerm->wtFlags |= TERM_LIKECOND;
}else{
pTerm->wtFlags |= TERM_CODED;
}
if( pTerm->iParent<0 ) break;
pTerm = &pTerm->pWC->a[pTerm->iParent];
pTerm->nChild--;
if( pTerm->nChild!=0 ) break;
nLoop++;
}
}
@@ -3807,6 +3838,7 @@ static Bitmask codeOneLoopStart(
*/
for(pTerm=pWC->a, j=pWC->nTerm; j>0; j--, pTerm++){
Expr *pE;
int skipLikeAddr = 0;
testcase( pTerm->wtFlags & TERM_VIRTUAL );
testcase( pTerm->wtFlags & TERM_CODED );
if( pTerm->wtFlags & (TERM_VIRTUAL|TERM_CODED) ) continue;
@@ -3821,7 +3853,13 @@ static Bitmask codeOneLoopStart(
if( pLevel->iLeftJoin && !ExprHasProperty(pE, EP_FromJoin) ){
continue;
}
if( pTerm->wtFlags & TERM_LIKECOND ){
assert( pLevel->iLikeRepCntr>0 );
skipLikeAddr = sqlite3VdbeAddOp1(v, OP_IfZero, pLevel->iLikeRepCntr);
VdbeCoverage(v);
}
sqlite3ExprIfFalse(pParse, pE, addrCont, SQLITE_JUMPIFNULL);
if( skipLikeAddr ) sqlite3VdbeJumpHere(v, skipLikeAddr);
pTerm->wtFlags |= TERM_CODED;
}