Re: [SQL] performance problems of a complex query with 2 subselects

>
> Hello!
>
> I am quite new to PostgreSQL and was hoping to use it as an alternative
> to MS Access for the product catalog software I am developing (the data
> is represented in a meta-model).
>
> I fully recreated the environment I had on MS Access (see attachment)
> and tried to run the query.
>
> The execution time for this query on MS Access for 40000 records was
> approx. 10 seconds.
> First the pgsql query on 400 records just seemed to hang. I installed a
> newer version of pgsql (6.4.2), created indices on the columns
> used until 'explain' showed only 1 'seq search' (couldn't get rid of
> that one).

You need to 'vacuum analyze <table>' for each table that you have created
AFTER you've created the indexes for them before the sql optimizer will
use the indexes. This should solve most of your speed issues. I also believe
that this is in the FAQ.

-=pierre