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#1 (**permalink**) 04-18-2008, 12:36 PM

> look at this:
> select count(*) from fotos where archivo not in (select archivo from
> archivos)
> Aggregate (cost=4899037992.36..4899037992.37 rows=1 width=0)
> -> Seq Scan on fotos (cost=22598.78..4899037338.07 rows=261716 width=0)
> Filter: (NOT (subplan))
> SubPlan
> -> Materialize (cost=22598.78..39304.22 rows=805344 width=58)
> -> Seq Scan on archivos (cost=0.00..13141.44 rows=805344
> width=58)
>
> I WILL DIE WAITING FOR QUERY RESPONSE !!!

Try:
select count(*) from fotos f where not exists (select archivo from archivos a where a.archivo = f.archivo)

select count(*) from
(
select archivo from fotos
except
select archivo from archivos
);

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#2 (**permalink**) 04-18-2008, 12:36 PM

On Wed, Oct 26, 2005 at 08:05:21AM -0400, Merlin Moncure wrote:
> select count(*) from fotos f where not exists (select archivo from archivos a where a.archivo = f.archivo)

This was an optimization before 7.4, but probably isn't anymore.

/* Steinar */
--
Homepage: http://www.sesse.net/

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