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RE: Why the optimizer is not choosing the best plan?

From: <ryan_gaffuri_at_comcast.net>
Date: Thu, 21 Oct 2004 13:30:56 +0000
Message-Id: <102120041330.20871.4177BA0F000DB71F000051872200750330079D9A00000E09A1020E979D@comcast.net>


we are using system stats here and we have noticed absolutely no difference whatsoever in oracles ability to make the best plan over using optimizer parameters. I've also noticed that even with bad optimizer init.ora settings in 9.2 the CBO is still write about 99% of the time. with decent settings that improves to 99.5% of the time. so if system stats helps its minimal.

> If you are on 9i then you should try to gather system statistics. This =
> may change the join method from NL to HJ.
>
> Regards, Joze=20
>
> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org =
> [mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Sami Seerangan
> Sent: Wednesday, October 20, 2004 9:49 PM
> To: Oracle Discussion List
> Subject: Why the optimizer is not choosing the best plan?
>

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Received on Thu Oct 21 2004 - 08:26:40 CDT

Original text of this message

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