Re: SQL optimization

[Dean Ware <d_ware@xxxxxxxxx>]

Excellent!

By changing the order of the tables being joined I reduced the execution 
time from 2800ms to 20ms!

Very useful command.

Thanks very much!


At 14:20 29/06/2001 -0300, you wrote:
> Are the fields been JOINed indexed? If not, they should.
>
> Have you tried an EXPLAIN command? Try it like EXPLAIN SELECT DISTINCT ....
> (and the rest of your query) It will bring a table stating what indexes are
> been chosen by MySQL to perform the query. It is worth trying to play with
> it until you get a faster join between tables.
>
> Hope it helps,
>
> >From a british-hearted chap from Brazil. :-)
>
> Tiago Luchini
> Diretor Técnico-Comercial
> Galluch Soluções Internet
> Telefax: 11 6912 3255
> Celular: 11 3176 7740
> http://www.galluch.com.br/

Dean Ware

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