Re: Optimizer change from 8i-9i

From: zhu chao <zhuchao_at_gmail.com>
Date: Thu, 12 May 2005 22:54:16 +0800
Message-ID: <962cf44b050512075424b9c54b@mail.gmail.com>

Hi, Chris,=20

    Thanks for your answer.=20
    I remember autotrace does not print the plan correctly, when histogram is used under certain conditions. But I am not sure now and I will do some test to verify it.

   And autotrace also have limit print the partition prune. (In your case and partition prune, it did not print the wrong plan , just with some limitation actualy, right?)

  Maybe other casae that it reported the wrong plan, I will keep it updated when I am aware of it.

> >Can I ask one more question , about the
> >"the index tie-break rule being the only reasonable exception, all
> >the other possibilities are a bit far fetched IMO"

>=20

> What do you mean???

>=20

> HTH
> Chris

>=20

Wolfgang email to me offline , and he said the index tie-break rule. But I have never heard of it before, so asking him about more detail.

As for the RBO part of your question, I don't think the RBO plans will change (the index tie-break rule being the only reasonable exception, all the other possibilities are a bit far fetched IMO).=20

--=20
Regards
Zhu Chao
www.cnoug.org

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Received on Thu May 12 2005 - 10:58:48 CDT