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Undo some unhelpful changes to skip-scan scoring that were added

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by the check-in [9e2b2681] that improved scoring of index scan.

FossilOrigin-Name: c7d51934a4f30d096bb79fc509fc9dd0df5d89a4
This commit is contained in:
drh
2016-07-29 01:32:36 +00:00
parent e37f7397c9
commit 99bbcc8287
5 changed files with 22 additions and 22 deletions
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4
src/where.c
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@@ -2478,11 +2478,11 @@ static int whereLoopAddBtreeIndex(
pNew->nSkip++;
pNew->aLTerm[pNew->nLTerm++] = 0;
pNew->wsFlags |= WHERE_SKIPSCAN;
nIter = pProbe->aiRowLogEst[saved_nEq]+1 - pProbe->aiRowLogEst[saved_nEq+1];
nIter = pProbe->aiRowLogEst[saved_nEq] - pProbe->aiRowLogEst[saved_nEq+1];
pNew->nOut -= nIter;
/* TUNING: Because uncertainties in the estimates for skip-scan queries,
** add a 1.375 fudge factor to make skip-scan slightly less likely. */
nIter += 4;
nIter += 5;
whereLoopAddBtreeIndex(pBuilder, pSrc, pProbe, nIter + nInMul);
pNew->nOut = saved_nOut;
pNew->u.btree.nEq = saved_nEq;