From: | "Steinar H(dot) Gunderson" <sgunderson(at)bigfoot(dot)com> |
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To: | Pepe Barbe <elventear(at)gmail(dot)com> |
Cc: | pgsql-performance(at)postgresql(dot)org |
Subject: | Re: Join performance |
Date: | 2007-11-08 22:51:20 |
Message-ID: | 20071108225120.GA22963@uio.no |
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Lists: | pgsql-performance |
On Thu, Nov 08, 2007 at 04:47:09PM -0600, Pepe Barbe wrote:
> I am having an issue on PostgreSQL 8.0.12. In the past we had performance
> issues with the query planner for queries on some tables where we knew we
> had indexes and it was doing a sequential scan, and for this reason we
> issue "SET enable_seqscan = FALSE" for some queries.
This is a bad idea in general. Did you really measure that this made queries
run faster? Generally, using an index is not always a win, and the planner
tries to figure out when it isn't. Setting it globally is seldom a good idea
anyway; if it really _is_ a win for a given query, you could always set it
locally in that session.
> Any ideas what could I try to fix this problem?
Re-enable seqscan?
/* Steinar */
--
Homepage: http://www.sesse.net/
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