Message-ID: <F001.0053A819.20030125095340@fatcity.com>
Date: Sat, 25 Jan 2003 09:53:40 -0800
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From: "Jonathan Lewis" <jonathan@jlcomp.demon.co.uk>
Subject: Re: Analytics Performance was RE: Tricky query question
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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:
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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 ;-)
>


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Author: Jonathan Lewis
  INET: jonathan@jlcomp.demon.co.uk

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