Re: SQL Help

On Fri, 26 Jan 2001, Mark A. Summers wrote:

> I am having trouble with the following query taking forever:
> -----
> SELECT * FROM ret108108_00, product
> WHERE ret108108_00."isbn" = product."Item1"
> 
> AND   product."SuperCategory" = '1'
> AND   product."PublisherCode" = 'ZON'
> ORDER BY ret108108_00.qty DESC LIMIT 100
> ----
> The problem is the second AND -- if I take this out it runs fine -- is there
> any way to optimize it ?  I had a similar problem with just Category so I
> created a new field in the product file called FullCat which combined
> SuperCategory and Category and thus eliminating the 2nd AND clause -- and
> that fixed it -- I just didn't want to do the same thing with Publisher.
> Before I tried to index Category, SuperCategory ... nothing seemed to help

Have you run a VACUUM ANALYZE on the table?  And what does
EXPLAIN show for the query?