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Re: I still believe CBO is better than RBO, but WTH?

From: Nuno Souto <nsouto_at_optushome.com.au.nospam>
Date: Fri, 07 Sep 2001 11:28:08 GMT
Message-ID: <3b98aeab.4921402@news>


On Thu, 06 Sep 2001 20:52:30 +0100, Connor McDonald <connor_mcdonald_at_yahoo.com> wrote:

>
>Given that there's some literals, do histograms give any benefit?
>

None whatsoever, as I said in my e-mail reply.

The thing I find deeply troubling is that the same SQL, with the same index, with the same execution plan, ends up running much, much faster with RBO than CBO!

Either the PLAN is utterly different and I'm not told about it, or ORACLE has decided to traverse indexes in a fundamentally different way when executing under CBO.

Either one is *not good*!!!

Cheers
Nuno Souto
nsouto_at_optushome.com.au.nospam Received on Fri Sep 07 2001 - 06:28:08 CDT

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