Re: Query improvement - Mailing list pgsql-performance

From Claudio Freire
Subject Re: Query improvement
Date
Msg-id BANLkTinqa_YBD+qhuNqta=M8rqaZNFtE5g@mail.gmail.com
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In response to Query improvement  (Mark <Marek.Balgar@seznam.cz>)
Responses Re: Query improvement  (Mark <Marek.Balgar@seznam.cz>)
Re: Query improvement  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-performance
On Sun, May 1, 2011 at 12:23 PM, Mark <Marek.Balgar@seznam.cz> wrote:
> Now the problem.
> When I try ANALYZE it shows:

That's a regular explain... can you post an EXPLAIN ANALYZE?

Hash joins are very inefficient if they require big temporary files.
I usually work around that by disabling hash joins for the problematic queries:

set enable_hashjoin = false;
<query>
set enable_hashjoin = true;

But an explain analyze would confirm or deny that theory.

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