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Re: "NOT IN" substantially slower in 9.0.2 than 8.3.13 - NOT EXISTS runs fast in both 8.3.13 and 9.0.2 - Mailing list pgsql-performance

From Mladen Gogala
Subject Re: "NOT IN" substantially slower in 9.0.2 than 8.3.13 - NOT EXISTS runs fast in both 8.3.13 and 9.0.2
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Msg-id 4D39CCA7.1040507@vmsinfo.com
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In response to Re: "NOT IN" substantially slower in 9.0.2 than 8.3.13 - NOT EXISTS runs fast in both 8.3.13 and 9.0.2  (Robert Haas <robertmhaas@gmail.com>)
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On 1/21/2011 12:51 PM, Robert Haas wrote:
> I am starting to suspect that there is a bug in the join selectivity
> logic in 9.0.  We've had a few complaints where the join was projected
> to return more rows than the product of the inner side and outer side
> of the join, which is clearly nonsense.  I read the function and I
> don't see anything weird... and it clearly can't be too bad or we
> would have had more complaints... but...

Well the way to test it would be to take the function from 8.3, input
the same arguments and see if there is any difference with the results.

--

Mladen Gogala
Sr. Oracle DBA
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