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Message Posted: Tue, 08 Oct 2013 @ 15:00:24 GMT


     
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Subj:   Expalin under estimating the stats calculation in 13.10 version
 
From:   Panchal, Hemanshu

Hi All,

I am working on a query which performs strange in different td version TD 12 to TD 13.10

For the given set of table considering same stats and same table structure (everything same except TD version) I am executing a subquery that returns 35000 rows(actual row count),

When the query is executed in TD 13.10 the explain underestimate the row count and show?s 800 rows which when joined to other table the query goes in product join condition

When the same query is executed in TD 12.0 then the explain overestimate the row count and shows 2 Million records which when joined to other table the query runs to success.

Any suggestion to override the underestimation ?caused by the TD 13.10 version.

Note : I already tried doing the oldrewrites on but no luck and query performs the same



     
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