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Re: why there is cost when I am running with RULE hint or optimizer_goal=RULE

From: Thomas Kyte <tkyte_at_oracle.com>
Date: 21 May 2002 09:24:06 -0700
Message-ID: <acdsb60173c@drn.newsguy.com>


In article <d983391a.0205201226.3548039b_at_posting.google.com>, d.rodri_at_consultant.com says...
>
>Hi
>
>I have this problem, I run a pretty big query under choose and rule
>and both shows costs in explain plan. I thought in RULE we dont see
>costs whatsoever?
>Also under RULE the explain plan shows hash join but then again I
>thought hash join can only be used in CBO?
>
>Am I missing something?

You are using some feature that forces CBO such as:

o table with non-default degree of paralellism o partitioned table
o index organized table
...

or you might have a query with a hint in it.

--
Thomas Kyte (tkyte@oracle.com)             http://asktom.oracle.com/ 
Expert one on one Oracle, programming techniques and solutions for Oracle.
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Opinions are mine and do not necessarily reflect those of Oracle Corp 
Received on Tue May 21 2002 - 11:24:06 CDT

Original text of this message

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