From: Michael Fuhr <mike@fuhr.org>
To: Michal Taborsky <michal.taborsky@mall.cz>
Cc: pgsql-performance@postgresql.org
Subject: Re: Searching union views not using indices
Date: Fri, 4 Nov 2005 08:12:57 -0700
Message-ID: <20051104151257.GA89760@winnie.fuhr.org> (raw)
In-Reply-To: <436B4836.7030300@mall.cz>
References: <436B4836.7030300@mall.cz>
On Fri, Nov 04, 2005 at 12:38:30PM +0100, Michal Taborsky wrote:
> SELECT object_id FROM commonview WHERE link_id=1234567
>
> The result is sequential scan on all tables, append, sort and then
> filter scan on this whole thing. Which of course is slow as hell. We use
> version 8.0.2.
I couldn't duplicate this in 8.0.4; I don't know if anything's
changed since 8.0.2 that would affect the query plan. Could you
post the EXPLAIN ANALYZE output? It might also be useful to see
the output with enable_seqscan disabled.
Have the tables been vacuumed and analyzed recently?
--
Michael Fuhr
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To: pgsql-performance@postgresql.org
Cc: mike@fuhr.org, michal.taborsky@mall.cz
Subject: Re: Searching union views not using indices
In-Reply-To: <20051104151257.GA89760@winnie.fuhr.org>
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