Re: Bad n_distinct estimation; hacks suggested?

From: Josh Berkus <josh(at)agliodbs(dot)com>
To: Marko Ristola <marko(dot)ristola(at)kolumbus(dot)fi>
Cc: pgsql-perform <pgsql-performance(at)postgresql(dot)org>
Subject: Re: Bad n_distinct estimation; hacks suggested?
Date: 2005-04-22 18:52:51
Message-ID: 200504221152.51736.josh@agliodbs.com
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Marko,

> Sometimes, if the random number generator, that PostgreSQL uses,
> isn't good enough, the randomly selected pages for the statistics
> might not be random enough.
>
> Solaris is unknown to me. Maybe the used random number generator there
> isn't good enough?

Hmmm. Good point. Will have to test on Linux.

--
--Josh

Josh Berkus
Aglio Database Solutions
San Francisco

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