Re: 8.4.7, incorrect estimate

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: "Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>,"Wayne Conrad" <wconrad(at)yagni(dot)com>
Cc: <pgsql-performance(at)postgresql(dot)org>
Subject: Re: 8.4.7, incorrect estimate
Date: 2011-05-02 16:04:56
Message-ID: 4DBE8FD8020000250003D101@gw.wicourts.gov
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Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> Wayne Conrad <wconrad(at)yagni(dot)com> writes:

>> Total runtime: 244572.432 ms

> I'll take a look at fixing that, but not sure if it'll be
> reasonable to back-patch or not. In the meantime, you need to
> look into restructuring the query to avoid nesting the EXISTS
> probes, if possible.

Wayne, I think your best bet at this point may be to just (INNER)
JOIN the three tables, and if there is a possibility of duplicates
to use SELECT DISTINCT.

-Kevin

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