Subject | Re: Upgrade to FB2.01 and performance drops |
---|---|
Author | trtoms |
Post date | 2007-05-20T19:07:05Z |
--- In firebird-support@yahoogroups.com, Fulvio Senore <mailing@...>
wrote:
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
wrote:
><snip> A few days ago I posted a message
>
> (http://tech.groups.yahoo.com/group/firebird-support/message/86039)if
> 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
> you want I can send you a sample database (less than 1 MB) that showsWe stopped using IN predicate some time ago wherever possible, as the
> the problem.
> Just let me know.
>
> Fulvio Senore
>
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