> From: Alexander V.Nevsky
> To: firebird-support@yahoogroups.com

[..]

> Raymond, let me answer in descending order.
> Why. Because FB serves IN (Select ...) scanning table in main select
> and performing subquery. Seemingly, MS SQL perform subselect once and
> perhaps use indices on main table if it is possible.

Can someone explain why FB performs the sub-select for each row in the main
select even if the sub-select is not correlated and will always return the
same resultset ?

Thanks.

--
Jerome