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Overview
| Comment: | Avoid unnecessary WHERE clause term tests when coding a join where one of the tables contains a OR constraint. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
512caa1ad30e6f699e2d006d5ab7674d |
| User & Date: | drh 2016-01-29 18:11:04 |
Context
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2016-01-30
| ||
| 02:10 | Make use of covering indexes in the OR optimization. check-in: 9de3d712 user: drh tags: trunk | |
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2016-01-29
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| 19:29 | Experimental attempt to make better use of covering indexes within OR queries. check-in: a323ac3a user: dan tags: covering-or | |
| 18:11 | Avoid unnecessary WHERE clause term tests when coding a join where one of the tables contains a OR constraint. check-in: 512caa1a user: drh tags: trunk | |
| 16:57 | Avoid unnecessary WHERE clause term tests when coding a join where one of the tables contains a OR constraint. Closed-Leaf check-in: ab946039 user: drh tags: OR-clause-improvement | |
| 08:38 | Avoid two more instances of pointer arithmetic on freed pointers. check-in: 2910ef64 user: dan tags: trunk | |
Changes
Changes to src/wherecode.c.
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*/
if( pWC->nTerm>1 ){
int iTerm;
for(iTerm=0; iTerm<pWC->nTerm; iTerm++){
Expr *pExpr = pWC->a[iTerm].pExpr;
if( &pWC->a[iTerm] == pTerm ) continue;
if( ExprHasProperty(pExpr, EP_FromJoin) ) continue;
if( (pWC->a[iTerm].wtFlags & TERM_VIRTUAL)!=0 ) continue;
if( (pWC->a[iTerm].eOperator & WO_ALL)==0 ) continue;
testcase( pWC->a[iTerm].wtFlags & TERM_ORINFO );
pExpr = sqlite3ExprDup(db, pExpr, 0);
pAndExpr = sqlite3ExprAnd(db, pAndExpr, pExpr);
}
if( pAndExpr ){
pAndExpr = sqlite3PExpr(pParse, TK_AND|TKFLG_DONTFOLD, 0, pAndExpr, 0);
|
| > > |
1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412 1413 |
*/
if( pWC->nTerm>1 ){
int iTerm;
for(iTerm=0; iTerm<pWC->nTerm; iTerm++){
Expr *pExpr = pWC->a[iTerm].pExpr;
if( &pWC->a[iTerm] == pTerm ) continue;
if( ExprHasProperty(pExpr, EP_FromJoin) ) continue;
testcase( pWC->a[iTerm].wtFlags & TERM_VIRTUAL );
testcase( pWC->a[iTerm].wtFlags & TERM_CODED );
if( (pWC->a[iTerm].wtFlags & (TERM_VIRTUAL|TERM_CODED))!=0 ) continue;
if( (pWC->a[iTerm].eOperator & WO_ALL)==0 ) continue;
testcase( pWC->a[iTerm].wtFlags & TERM_ORINFO );
pExpr = sqlite3ExprDup(db, pExpr, 0);
pAndExpr = sqlite3ExprAnd(db, pAndExpr, pExpr);
}
if( pAndExpr ){
pAndExpr = sqlite3PExpr(pParse, TK_AND|TKFLG_DONTFOLD, 0, pAndExpr, 0);
|