SQLite

Check-in [9d05777fe2]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Try to factor constant subcomponents of the WHERE clause out of the loop.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 9d05777fe24e1a5ce71762de38db840931ef0bc8
User & Date: drh 2014-01-02 21:05:10.654
Context
2014-01-03
16:03
Avoid some unnecessary OP_SCopy operations when inserting into a table with multiple indices. (check-in: 429018b19c user: drh tags: trunk)
2014-01-02
21:05
Try to factor constant subcomponents of the WHERE clause out of the loop. (check-in: 9d05777fe2 user: drh tags: trunk)
19:35
Avoid unnecessary affinity transformations when building indices using data from a table. (check-in: 10d851353c user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/where.c.
︙︙
5426
5427
5428
5429
5430
5431
5432

5433

5434
5435


5436
5437
5438
5439
5440
5441
5442

  whereClauseInit(&pWInfo->sWC, pWInfo);
  whereSplit(&pWInfo->sWC, pWhere, TK_AND);
  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
    
  /* Special case: a WHERE clause that is constant.  Evaluate the
  ** expression and either jump over all of the code or fall thru.
  */

  if( pWhere && (nTabList==0 || sqlite3ExprIsConstantNotJoin(pWhere)) ){

    sqlite3ExprIfFalse(pParse, pWhere, pWInfo->iBreak, SQLITE_JUMPIFNULL);
    pWhere = 0;


  }

  /* Special case: No FROM clause
  */
  if( nTabList==0 ){
    if( pOrderBy ) pWInfo->bOBSat = 1;
    if( wctrlFlags & WHERE_WANT_DISTINCT ){








>
|
>
|
<
>
>








5426
5427
5428
5429
5430
5431
5432
5433
5434
5435
5436

5437
5438
5439
5440
5441
5442
5443
5444
5445

  whereClauseInit(&pWInfo->sWC, pWInfo);
  whereSplit(&pWInfo->sWC, pWhere, TK_AND);
  sqlite3CodeVerifySchema(pParse, -1); /* Insert the cookie verifier Goto */
    
  /* Special case: a WHERE clause that is constant.  Evaluate the
  ** expression and either jump over all of the code or fall thru.
  */
  for(ii=0; ii<sWLB.pWC->nTerm; ii++){
    if( nTabList==0 || sqlite3ExprIsConstantNotJoin(sWLB.pWC->a[ii].pExpr) ){
      sqlite3ExprIfFalse(pParse, sWLB.pWC->a[ii].pExpr, pWInfo->iBreak,
                         SQLITE_JUMPIFNULL);

      sWLB.pWC->a[ii].wtFlags |= TERM_CODED;
    }
  }

  /* Special case: No FROM clause
  */
  if( nTabList==0 ){
    if( pOrderBy ) pWInfo->bOBSat = 1;
    if( wctrlFlags & WHERE_WANT_DISTINCT ){
︙︙