Re: strange row count estimates with conditions on multiple column

From: Tomas Vondra <tv(at)fuzzy(dot)cz>
To: pgsql-general(at)postgresql(dot)org
Subject: Re: strange row count estimates with conditions on multiple column
Date: 2010-11-17 05:35:34
Message-ID: 4CE369A6.80701@fuzzy.cz
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> BTW I think the default estimate used to be 1000, so it was changed in
> one of the 8.x releases? Can you point me to the docs? I've even tried
> to find that in the sources, but unsuccessfully.

OK, I've found it right after submitting the e-mail.

It's defined in selfuncs.h as DEFAULT_RANGE_INEQ_SEL, equal 0.005. Which
makes sense, as it's related to the table size. I've mixed that with
some other default which used to be 1000 (table size I think).

regards
Tomas

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