RE: Better cardinality estimate when dialing optimizer_features_enable back

From: Allen, Brandon <Brandon.Allen_at_OneNeck.com>
Date: Tue, 24 Nov 2009 09:53:10 -0700
Message-ID: <64BAF54438380142A0BF94A23224A31E112E9EEC8A_at_ONEWS06.oneneck.corp>



Have you considered just creating a stored outline (or sql profile if you have the tuning pack) to lock in your favorite explain plan?

Why would you want to create histograms on all indexed columns? You might want to try removing all histograms on the columns involved with this query to see if that helps, or only gather histograms for columns with skewonly.

I think it might be helpful if you can provide the output of "select * from table(dbms_xplan.display_cursor(3841154485,0,'IOSTATS LAST'));", if this is the query you're trying to tune, but you'll need to turn on a 10046 trace for the query in order to gather plan level stats.

Regards,
Brandon



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Received on Tue Nov 24 2009 - 10:53:10 CST

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