--- In firebird-support@yahoogroups.com, Fulvio Senore <mailing@...>
wrote:

>
>

<snip> A few days ago I posted a message

> (http://tech.groups.yahoo.com/group/firebird-support/message/86039)
> about a query using 'IN' and a subquery: it was deadly slow.
> I am using V2.0.1 and I don't know how it could work with V1.5, but

if

> you want I can send you a sample database (less than 1 MB) that shows
> the problem.
> Just let me know.
>
> Fulvio Senore
>

We stopped using IN predicate some time ago wherever possible, as the
general case seemed to be better using EXISTS instead. Of course,
there's no "one size fits all" option for every query, but EXISTS will
back out of the test when the first satisfying result is detected, and
this can often save time.

Trevor