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Re: optimizer_max_permutations

From: Tanel Põder <tanel.poder.003_at_mail.ee>
Date: Thu, 4 Mar 2004 01:45:50 +0200
Message-ID: <0df301c40179$a8d0e6f0$a2a623d5@porgand>


Note that even if you set optimizer_max_permutation to a small value, then big multitable joins may still use more permutations than set by o_m_p parameter.

This behaviour is dependent on number of tables in join and _optimizer_search_limit parameter. Ixora has more information on it.

Tanel.

> I've been talking to Oracle Support about some performance problems and
they told me to set optimizer_max_permutations=2000
>
> Has anyone tested how this effects the CBO? This is on 9.2.0.4 on Solaris.
>
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Received on Wed Mar 03 2004 - 17:47:47 CST

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