On Wed, Apr 06, 2005 at 02:59:18PM -0300, Ricardo Valen?a de Assis wrote:
> 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)

Well, neither of those should take very long at all. What's EXPLAIN
ANALYZE show?
--
Jim C. Nasby, Database Consultant decibel@decibel.org
Give your computer some brain candy! www.distributed.net Team #1828

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