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Re: Which plan is better - what COST really means ?

From: Jaffar_DBA <sjaffarhussain_at_gmail.com>
Date: Thu, 13 Jan 2005 12:00:51 +0300
Message-ID: <97b7fd2f0501130100b111117@mail.gmail.com>


I definately agree with about what toms is saying. I had expereince where higher COST queries much father than lower COST queries in the CBO. Taking consideration of response time would be more better than COST of the query.

On 13 Jan 2005 08:57:11 -0000, Prem Khanna J <premj_at_rediffmail.com> wrote:
> Friends,
> when i have got two plans , how do i decide
> which one is the best ?
>
> just read in asktom , that COST of a plan ,
> does not have any correspondence with response
> time of a query.
>
> i.e.,a query with higher COST than another
> can be faster.
>
> if so , what in the execution plan does help
> me to decide about a good (faster) plan ?
>
> unless i execute it , can't i know it ?
> is that the only way !!!
>
> Can someone throw light on this ?
> The environment is oracle 9.2.0.4/AIX5.2L.
>
> Thanks in advance.
>
> Regards,
> Prem.
> --
> http://www.freelists.org/webpage/oracle-l
>

-- 
Best Regards,
Jaffar, OCP DBA
Banque Saudi Fransi
Saudi Arabia
--
http://www.freelists.org/webpage/oracle-l
Received on Thu Jan 13 2005 - 02:55:56 CST

Original text of this message

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