Re: Accelerating subqueries

Fabrice Scemama wrote:
> 
> Hi fellow PostgreSQL users.
> 
> Here's a query:
> 
> DELETE FROM Annonces WHERE Id_Ag IN
> (
>     SELECT Id FROM Installs
>     WHERE Si_Compte_Actif = 'f'
> );

The IN Clause is known to be very very slow. Use the
EXISTS Clause instead. 

Regards Herbie
-- 
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Herbert Liechti                     E-Mail: Herbert.Liechti@thinx.ch
ThinX networked business services        Stahlrain 10, CH-5200 Brugg
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