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Re: Re: which should be faster

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Mon, 05 May 2003 10:49:46 -0800
Message-ID: <F001.0058FE9B.20030505104946@fatcity.com>

What I tried to say over the weekend was:

Predicate order should not matter in 9i
because you should be using CPU costing, and Oracle 9i will re-arrange predicate ordering to minimise CPU load, and report this fact in the explain plan.

Predicate order CAN have an impact on
8.1.7 because Oracle 8i (and earlier) does not consider CPU cost when working out
an execution plan.

Regards

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

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> jonathan lewis posted over the weekend that it does. He said it does
in 9i unless you have a certain parameter set. Cant remember what that was off-hand.
>
> >
> > From: "AK" <oramagic_at_hotmail.com>
> > Date: 2003/05/05 Mon AM 11:46:41 EDT
> > To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
> > Subject: Re: which should be faster
> >
> > does predicate order makes diff in cob also ?
> > oracle 8.1.7
> >

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

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Received on Mon May 05 2003 - 13:49:46 CDT

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