DATABASE=# explain delete from usuario where
usua_cd_usuario=backup.usua_cd_usuario;
QUERY PLAN
--------------------------------------------------------------------
Hash Join (cost=5.71..644.15 rows=298 width=6)
Hash Cond: ("outer".usua_cd_usuario = "inner".usua_cd_usuario)
-> Seq Scan on usuario (cost=0.00..516.64 rows=23764 width=10)
-> Hash (cost=4.97..4.97 rows=297 width=4)
-> Seq Scan on backup (cost=0.00..4.97 rows=297 width=4)
(5 rows)
DATABASE=# explain delete from usuario where usua_cd_usuario in (select
usua_cd_usuario from backup);
QUERY PLAN
--------------------------------------------------------------------
Hash IN Join (cost=5.71..644.15 rows=298 width=6)
Hash Cond: ("outer".usua_cd_usuario = "inner".usua_cd_usuario)
-> Seq Scan on usuario (cost=0.00..516.64 rows=23764 width=10)
-> Hash (cost=4.97..4.97 rows=297 width=4)
-> Seq Scan on backup (cost=0.00..4.97 rows=297 width=4)
(5 rows)
----- Original Message -----
From: "Jim C. Nasby" <decibel@decibel.org>
To: "Ricardo Valen?a de Assis" <valenca@campusvirtual.br>
Cc: "Bruno Wolff III" <bruno@wolff.to>; <pgsql-admin@postgresql.org>
Sent: Wednesday, April 06, 2005 2:56 PM
Subject: Re: [ADMIN] delete to slow
> On Wed, Apr 06, 2005 at 02:32:55PM -0300, Ricardo Valen?a de Assis wrote:
> > I?ve tried... It takes the same time. I used explain and I saw it...
Exactly
> > the same time.
>
> And what does explain show? Are statistics up to date?
> --
> Jim C. Nasby, Database Consultant decibel@decibel.org
> Give your computer some brain candy! www.distributed.net Team #1828
>
> Windows: "Where do you want to go today?"
> Linux: "Where do you want to go tomorrow?"
> FreeBSD: "Are you guys coming, or what?"