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Re: 7.1.2 query now uses hash-join instead of nested loop - Mailing list pgsql-general

From Tom Lane
Subject Re: 7.1.2 query now uses hash-join instead of nested loop
Date
Msg-id 1873.992877108@sss.pgh.pa.us
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In response to 7.1.2 query now uses hash-join instead of nested loop  ("Tim Knowles" <timknowles@ametco.co.uk>)
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"Tim Knowles" <timknowles@ametco.co.uk> writes:
>     I have two machines one running 7.1.1 and the other 7.1.2.  I've used
> pg_dump to dump the schema and data from the 7.1.1 system and loaded it into
> 7.1.2 for testing.  Some of my queries now run a lot slower as the planner
> prefers to use a hash-join instead of a nested loop.

AFAICS from the CVS change logs, there is no difference in planning
between 7.1.1 and 7.1.2.  Perhaps you neglected to run VACUUM ANALYZE
on one case or the other?  The difference in estimated result rows seems
awfully large...

            regards, tom lane

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