From: Tom Lane <tgl@sss.pgh.pa.us>
To: Daniele Varrazzo <piro@develer.com>
Cc: Francisco Reyes <lists@stringsutils.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: An "obvious" index not being used
Date: Sun, 20 Jul 2008 00:44:47 -0400
Message-ID: <24818.1216529087@sss.pgh.pa.us> (raw)
In-Reply-To: <488222A7.1000202@develer.com>
References: <4859B13F.3070103@develer.com>
<10923.1213839814@sss.pgh.pa.us>
<4859C24F.6000503@develer.com>
<cone.1216431907.692690.79328.1000@zoraida.natserv.net>
<488222A7.1000202@develer.com>
Daniele Varrazzo <piro@develer.com> writes:
> In my problem I had 2 tables: a small one (accounts), a large one (foo). The
> way the query is written doesn't allow the stats from the large table to be
> used at all, unless the records from the small table are fetched. This is
> independent from the stats accuracy.
> What the planner does is to assume an even distribution in the data in the
> joined fields.
Sir, you don't know what you're talking about.
regards, tom lane
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To: pgsql-performance@postgresql.org
Cc: tgl@sss.pgh.pa.us, piro@develer.com, lists@stringsutils.com
Subject: Re: An "obvious" index not being used
In-Reply-To: <24818.1216529087@sss.pgh.pa.us>
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