Subject RE: [firebird-support] Optimizer request
Author Leyne, Sean
> Still no changes. This looks to me as a riddle.

> select orders.*
> from
> (select partid from partners where = ‘Spain’) T
> JOIN orders ON orders.partid = T.partid

Do you have an index on

If not, how do you expect the system to optimize the search?

The engine would need to perform a scan of the partners table...