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Re: Optimzer Oddities

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Fri, 30 Apr 2004 16:18:42 +0000 (UTC)
Message-ID: <c6tu92$keq$1@sparta.btinternet.com>

The optimizer can rewrite subqueries that contain aggregates to turn them into joins, and has been able to for quite some time.

After a couple of minutes thought, I can't come up with a way to rewrite this particular query.

-- 
Regards

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

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"srivenu" <srivenu_at_hotmail.com> wrote in message
news:1a68177.0404292315.4857ad7e_at_posting.google.com...

> Jonathan,
> Please correct me if i'am wrong in making the observation that since
> the sub query contains an aggregate function, the optimizer cannot
> rewrite the query and covert it into a join.
> Or are there any other ways that the CBO might rewrite the query ?
> thanks & regards
> Srivenu
Received on Fri Apr 30 2004 - 11:18:42 CDT

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