Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Small size reduction and performance improvement in whereScanNext(). |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
d861ee17eb900a607de6ec3f4a5d5c24 |
| User & Date: | drh 2016-10-26 17:57:40.045 |
Context
|
2016-10-26
| ||
| 18:41 | Small size reduction and performance enhancement in whereScanInit(). (check-in: c23f5ef337 user: drh tags: trunk) | |
| 17:57 | Small size reduction and performance improvement in whereScanNext(). (check-in: d861ee17eb user: drh tags: trunk) | |
| 16:05 | If all branches of an OR optimize scan that is the rhs of a LEFT JOIN use the same index, set the index cursor to return NULL values if there are no matches for a row on the lhs. Fix for ticket [34a579141b2c5ac] (check-in: ec9dab8054 user: dan tags: trunk) | |
Changes
Changes to src/where.c.
| ︙ | ︙ | |||
194 195 196 197 198 199 200 | int iCur; /* The cursor on the LHS of the term */ i16 iColumn; /* The column on the LHS of the term. -1 for IPK */ Expr *pX; /* An expression being tested */ WhereClause *pWC; /* Shorthand for pScan->pWC */ WhereTerm *pTerm; /* The term being tested */ int k = pScan->k; /* Where to start scanning */ | | | > | > > | 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 |
int iCur; /* The cursor on the LHS of the term */
i16 iColumn; /* The column on the LHS of the term. -1 for IPK */
Expr *pX; /* An expression being tested */
WhereClause *pWC; /* Shorthand for pScan->pWC */
WhereTerm *pTerm; /* The term being tested */
int k = pScan->k; /* Where to start scanning */
assert( pScan->iEquiv<=pScan->nEquiv );
pWC = pScan->pWC;
while(1){
iColumn = pScan->aiColumn[pScan->iEquiv-1];
if( iColumn==XN_EXPR && pScan->pIdxExpr==0 ) return 0;
iCur = pScan->aiCur[pScan->iEquiv-1];
assert( pWC!=0 );
do{
for(pTerm=pWC->a+k; k<pWC->nTerm; k++, pTerm++){
if( pTerm->leftCursor==iCur
&& pTerm->u.leftColumn==iColumn
&& (iColumn!=XN_EXPR
|| sqlite3ExprCompare(pTerm->pExpr->pLeft,pScan->pIdxExpr,iCur)==0)
&& (pScan->iEquiv<=1 || !ExprHasProperty(pTerm->pExpr, EP_FromJoin))
){
|
| ︙ | ︙ | |||
248 249 250 251 252 253 254 255 256 257 258 259 |
&& (pX = pTerm->pExpr->pRight)->op==TK_COLUMN
&& pX->iTable==pScan->aiCur[0]
&& pX->iColumn==pScan->aiColumn[0]
){
testcase( pTerm->eOperator & WO_IS );
continue;
}
pScan->k = k+1;
return pTerm;
}
}
}
| > | | > | | 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 |
&& (pX = pTerm->pExpr->pRight)->op==TK_COLUMN
&& pX->iTable==pScan->aiCur[0]
&& pX->iColumn==pScan->aiColumn[0]
){
testcase( pTerm->eOperator & WO_IS );
continue;
}
pScan->pWC = pWC;
pScan->k = k+1;
return pTerm;
}
}
}
pWC = pWC->pOuter;
k = 0;
}while( pWC!=0 );
if( pScan->iEquiv>=pScan->nEquiv ) break;
pWC = pScan->pOrigWC;
k = 0;
pScan->iEquiv++;
}
return 0;
}
/*
|
| ︙ | ︙ |