RE: Updates with correlated subqueries slow after 9.2->10.2 upgrade
- From: "Allen, Brandon" <Brandon.Allen@xxxxxxxxxxx>
- To: "nkodner@xxxxxxxxx" <nkodner@xxxxxxxxx>, Greg Rahn <greg@xxxxxxxxxxxxxxxxxx>, "oracle-l@xxxxxxxxxxxxx" <oracle-l@xxxxxxxxxxxxx>
- Date: Tue, 17 Nov 2009 15:44:19 -0700
Greg made an excellent point, and I'll add that your cardinality estimates can
still be way off, even with estimate_percent=> 100, if you have skewed data and
no histograms (or inaccurate histograms) or various other conditions, so it
would still be a good idea to verify your cardinality estimates.
Regards,
Brandon
From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On
Behalf Of Neil Kodner
I'm using
estimate_percent=>100 and method_opt=>'FOR ALL COLUMNS SIZE 1' for these tables
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