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Commit1afaa25

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If we cannot get a real estimate for the selectivity of a range query,
use a default value that's fairly small. We were generating a resultof about 0.1, but I think 0.01 is probably better --- want to encourageuse of an indexscan in this situation.
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‎src/backend/optimizer/path/clausesel.c‎

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@@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/clausesel.c,v 1.31 2000/03/17 02:36:14 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/optimizer/path/clausesel.c,v 1.32 2000/03/23 00:58:36 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
@@ -194,9 +194,11 @@ clauselist_selectivity(Query *root,
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else
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{
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/* One or both is probably a default estimate,
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* so punt and just merge them in generically.
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* so supply a default estimate for the selectivity
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* of the range query. We rather optimistically assume
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* that the range is tight...
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*/
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s1 *=rqlist->hibound*rqlist->lobound;
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s1 *=0.01;
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}
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}
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else

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