Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Avoid an unnecessary OP_IfNull while doing an indexed search. |
|---|---|
| Downloads: | Tarball | ZIP archive | SQL archive |
| Timelines: | family | ancestors | descendants | both | trunk |
| Files: | files | file ages | folders |
| SHA1: |
5196000930600d0cd931b87e86450779 |
| User & Date: | drh 2013-11-13 08:55:02 |
Context
|
2013-11-13
| ||
| 17:58 | Add the "PRAGMA vdbe_eqp" command, only available with SQLITE_DEBUG. Simplify some of the other debugging logic. check-in: 8ce33f4c user: drh tags: trunk | |
| 12:27 | Add the ability to use an index even if the left-most columns of the index are unconstrainted, provided that the left-most columns have few distinct values. check-in: 27dd5993 user: drh tags: skip-scan | |
| 08:55 | Avoid an unnecessary OP_IfNull while doing an indexed search. check-in: 51960009 user: drh tags: trunk | |
|
2013-11-12
| ||
| 21:37 | Adjust the SQLITE_MALLOCSIZE defines, primarily to make sure _msize gets used with MSVC when appropriate. check-in: 4e7e805e user: mistachkin tags: trunk | |
Changes
Changes to src/where.c.
3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 |
/* If there are inequality constraints, check that the value
** of the table column that the inequality contrains is not NULL.
** If it is, jump to the next iteration of the loop.
*/
r1 = sqlite3GetTempReg(pParse);
testcase( pLoop->wsFlags & WHERE_BTM_LIMIT );
testcase( pLoop->wsFlags & WHERE_TOP_LIMIT );
if( (pLoop->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0 ){
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
sqlite3VdbeAddOp2(v, OP_IsNull, r1, addrCont);
}
sqlite3ReleaseTempReg(pParse, r1);
/* Seek the table cursor, if required */
disableTerm(pLevel, pRangeStart);
disableTerm(pLevel, pRangeEnd);
|
| > > > > |
3112 3113 3114 3115 3116 3117 3118 3119 3120 3121 3122 3123 3124 3125 3126 3127 3128 3129 3130 3131 |
/* If there are inequality constraints, check that the value
** of the table column that the inequality contrains is not NULL.
** If it is, jump to the next iteration of the loop.
*/
r1 = sqlite3GetTempReg(pParse);
testcase( pLoop->wsFlags & WHERE_BTM_LIMIT );
testcase( pLoop->wsFlags & WHERE_TOP_LIMIT );
if( (pLoop->wsFlags & (WHERE_BTM_LIMIT|WHERE_TOP_LIMIT))!=0
&& (j = pIdx->aiColumn[nEq])>=0
&& pIdx->pTable->aCol[j].notNull==0
){
sqlite3VdbeAddOp3(v, OP_Column, iIdxCur, nEq, r1);
VdbeComment((v, "%s", pIdx->pTable->aCol[j].zName));
sqlite3VdbeAddOp2(v, OP_IsNull, r1, addrCont);
}
sqlite3ReleaseTempReg(pParse, r1);
/* Seek the table cursor, if required */
disableTerm(pLevel, pRangeStart);
disableTerm(pLevel, pRangeEnd);
|