Re: Analytics Performance was RE: Tricky query question

An odd thing, though. Sometimes the query that is (a little) slower when run stand-alone is the better bet when run in a highly concurrent environment because of latching issues.

Converting self-joins to analytics can, on occasion, increase CPU usage but reduce latching - a strategy that seems to be favoured in recent versions of the Oracle kernel.

Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Coming soon a new one-day tutorial:
Cost Based Optimisation
(see http://www.jlcomp.demon.co.uk/tutorial.html )

____UK_______March
____USA_(FL)_May

Next Seminar dates:
(see http://www.jlcomp.demon.co.uk/seminar.html )

____USA_(CA, TX)_August

The Co-operative Oracle Users' FAQ
http://www.jlcomp.demon.co.uk/faq/ind_faq.html
>
>Though I've never built test cases showing the counter examples, I'm
sure it
>would be pretty easy to build some where the analytics is going to be
>slower. FWIW, another person on the list *is* working on such counter
>examples ;-)
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: Jonathan Lewis
  INET: jonathan_at_jlcomp.demon.co.uk

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).