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From: postgresql@foo.me.uk
To: 'postgres performance list' <pgsql-performance@postgresql.org>
Subject: Re: Slow query: bitmap scan troubles
Date: Thu, 6 Dec 2012 12:56:26 -0000
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> I also wonder if increasing (say x10) of default_statistics_target or just
doing ALTER TABLE SET STATISTICS for particular tables will help.
> It will make planned to produce more precise estimations. Do not forget
ANALYZE afer changing it.

Thanks Sergey, I will try this too.

I think the bother here is that this statistics are pretty good (we do
analyse regularly and default_statistics_target is already 1000), but once I
start filtering the two tables the correlations alter quite a bit. I don't
think there is that much that can be done about that :)

- Phil




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