Re: [SQL] query with subquery abnormally slow?

On Mon, Nov 01, 1999 at 07:47:07PM +0100, Oskar Liljeblad wrote:
> I'm doing a SELECT query with a subquery on a table with 12K rows
> but it is very slow (10 seconds+). The query looks like this:
>
> select *
> from items
> where package in
> (select package
> from items
> where ...blah...
> group by package)

I could do it much faster with this query:

select distinct i2.package, i1.*
from items i1, items i2
where i1.package = i2.package
and ...blah...

but it is still at least three times slower than
doing the subquery first, and for each row in the
result another query. Any ideas?

Oskar Liljeblad (osk(at)hem(dot)passagen(dot)se)