At 06/08/2002 05:37 PM, you wrote:

>Hi, i have about 400,000 records on my table Cliente and about
>400,000 on
>Cliente_Mailing and when i run this query:
>
>Select Cliente.Nome
> From Cliente,Cliente_Mailing Where
> (Cliente_Mailing.id_mailing=9 or Cliente_Mailing.id_mailing=8)
> and Cliente.id_cliente=Cliente_Mailing.id_cliente
> Order by nome
>
>It Takes about 24 minutes
>
>But if i test only Cliente_Mailing.id_mailing=9 like this:
>Select Cliente.Nome
> From Cliente,Cliente_Mailing Where
> (Cliente_Mailing.id_mailing=9)
> and Cliente.id_cliente=Cliente_Mailing.id_cliente
> Order by nome
>
>it takes 1 second
>
>Why and how to speed the top query

Try:

SELECT Cliente.Nome
FROM Cliente
WHERE EXISTS (SELECT *
FROM Cliente_Mailing
WHERE (Cliente_Mailing.id_cliente=Cliente.id_cliente)
AND (Cliente_Mailing.id_mailing in [8, 9]))
ORDER BY Nome


Daniel Rail
Senior System Engineer
ACCRA Group Inc. (www.accra.ca)
ACCRA Med Software Inc. (www.accramed.ca)