Re: problems doing sub-selects on PostgreSQL 7.1.3 and - Mailing list pgsql-admin

>     SELECT count(*) FROM users WHERE id NOT IN ( SELECT users_id FROM users_demographics );

I'm not sure about the difference in speed,  but try the following for a
much faster query:

SELECT count(id)
FROM users

EXCEPT

SELECT users_id
FROM  users_demographics

Should be a great deal faster.

- Brandon



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 b. palmer,  bpalmer@crimelabs.net           pgp:crimelabs.net/bpalmer.pgp5