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Overview
Comment:Better estimatedCost in the xBestIndex method of the generate_series vtab.
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SHA1: f2c16094a536e7ef62444d0fe38cbee2a4999426
User & Date: drh 2016-03-01 02:11:50.810
Context
2016-03-01
22:41
Improved debugging output with wheretrace. Fix some typos in test script comments. (check-in: 13a37fd487 user: drh tags: trunk)
18:07
Add test code useful for testing the planners use of teh virtual table xBestIndex() method. (check-in: de034c0db6 user: dan tags: test-bestindex)
02:11
Better estimatedCost in the xBestIndex method of the generate_series vtab. (check-in: f2c16094a5 user: drh tags: trunk)
2016-02-29
17:34
Fix a problem in fts5 where a corrupt db could lead to a (huge) buffer overread. (check-in: c9a30e117f user: dan tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to ext/misc/series.c.
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  if( stepIdx>=0 ){
    pIdxInfo->aConstraintUsage[stepIdx].argvIndex = ++nArg;
    pIdxInfo->aConstraintUsage[stepIdx].omit = 1;
  }
  if( (idxNum & 3)==3 ){
    /* Both start= and stop= boundaries are available.  This is the 
    ** the preferred case */
    pIdxInfo->estimatedCost = (double)1;
    pIdxInfo->estimatedRows = 1000;
    if( pIdxInfo->nOrderBy==1 ){
      if( pIdxInfo->aOrderBy[0].desc ) idxNum |= 8;
      pIdxInfo->orderByConsumed = 1;
    }
  }else{
    /* If either boundary is missing, we have to generate a huge span








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  if( stepIdx>=0 ){
    pIdxInfo->aConstraintUsage[stepIdx].argvIndex = ++nArg;
    pIdxInfo->aConstraintUsage[stepIdx].omit = 1;
  }
  if( (idxNum & 3)==3 ){
    /* Both start= and stop= boundaries are available.  This is the 
    ** the preferred case */
    pIdxInfo->estimatedCost = (double)(2 - ((idxNum&4)!=0));
    pIdxInfo->estimatedRows = 1000;
    if( pIdxInfo->nOrderBy==1 ){
      if( pIdxInfo->aOrderBy[0].desc ) idxNum |= 8;
      pIdxInfo->orderByConsumed = 1;
    }
  }else{
    /* If either boundary is missing, we have to generate a huge span
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