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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