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Re: Does Optimizer use P.A.T to calculate cost..?

From: <mccmx_at_hotmail.com>
Date: 27 Oct 2006 06:17:23 -0700
Message-ID: <1161955043.086095.304490@m73g2000cwd.googlegroups.com>


> Time to start investigating what is happening, a 10046 trace at level 8
> will help. Also, take a look at the output of this SQL statement:

The 10046 hasn't helped. It has just shown me that the plan has changed. I've done some tests and I can confirm that I can get much more stable execution times if I use the old method of manually specifying *_area_size parameters.

I've seen advice on this newsgroup which says that you can set the PGA target to a very high value as long as you have the memory available.

But I am seeing that a value that is too high can cause instablity in execution plans.

Matt Received on Fri Oct 27 2006 - 08:17:23 CDT

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