Decide upon which query to choose.

I've a couple of SQL queries both performing the same task.(ie.the result set of the two queries being the same).
Now,How would I decide which of the two to go with?
Would it be ok if I decide with the costs of the two queries.ie choose the one with min. cost?
Regards,
Bhagat

According to Tom Kyte, one cannot do this. The CBO costs from one execution plan can never be related to another execution plan - even for the same SQL.
http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:313416745628
Quote. "Don't compare them, you cannot -- they might as well be random numbers." Unquote.
I think Jonathan Lewis may have a slightly different take on this. (hint, hint Jonathan - you're here? ;-) ).
Must admit that I have often used the cost between to plans for the same SQL as a deciding factor - which from reading Tom's response is not a very bright idea.

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799301 wrote:
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Chhers,

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Decide upon which query to choose.

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