From: Richard Huxton <dev@archonet.com>
To: Albert Cervera Areny <albert@sedifa.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Posible planner improvement?
Date: Wed, 21 May 2008 11:48:05 +0100
Message-ID: <4833FDE5.8090603@archonet.com> (raw)
In-Reply-To: <200805211228.48248.albert@sedifa.com>
References: <200805211228.48248.albert@sedifa.com>
Albert Cervera Areny wrote:
> I've got a query similar to this:
>
> select * from t1, t2 where t1.id > 158507 and t1.id = t2.id;
>
> That took > 84 minutes (the query was a bit longer but this is the part that
> made the difference) after a little change the query took ~1 second:
>
> select * from t1, t2 where t1.id > 158507 and t2.id > 158507 and t1.id =
> t2.id;
Try posting EXPLAIN ANALYSE SELECT ... for both of those queries and
we'll see why it's better at the second one.
--
Richard Huxton
Archonet Ltd
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To: pgsql-performance@postgresql.org
Cc: dev@archonet.com, albert@sedifa.com
Subject: Re: Posible planner improvement?
In-Reply-To: <4833FDE5.8090603@archonet.com>
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