From: Josh Berkus <josh@agliodbs.com>
To: Manuel Sugawara <masm@fciencias.unam.mx>
To: pgsql-sql@postgresql.org
Subject: Re: left join on a view takes significantly more time.
Date: Wed, 31 Mar 2004 15:49:29 -0800
Message-ID: <200403311549.29211.josh@agliodbs.com> (raw)
In-Reply-To: <m3wu50voaq.fsf@conexa.fciencias.unam.mx>
References: <m3wu50voaq.fsf@conexa.fciencias.unam.mx>
Manuel,
> I'm facing a wired problem. When I left join two tables PostgreSQL is
> able to do it fast using the corresponding indices, However, if I
> define a simple view (to format the data) on one of the tables, the
> left join does not use the indices. Is something wrong here?
At a guess, the complex CASE statements are causing the planner to behave
badly. What happens if you do a straight join and not a left join?
Also, it's generally a good idea to put your join expression in the same order
as the referenced tables. You confused me and you could confuse the planner
at some stage.
--
-Josh Berkus
Aglio Database Solutions
San Francisco
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To: pgsql-sql@postgresql.org
Cc: josh@agliodbs.com, masm@fciencias.unam.mx
Subject: Re: left join on a view takes significantly more time.
In-Reply-To: <200403311549.29211.josh@agliodbs.com>
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