RE: more on 'high cpu...'

From: Bobak, Mark <Mark.Bobak_at_il.proquest.com>
Date: Mon, 2 Jul 2007 12:27:23 -0400
Message-ID: <AA29A27627F842409E1D18FB19CDCF270CABBA37@AABO-EXCHANGE02.bos.il.pqe>

Sure, the DISTINCT is forcing a sort. Depending on the view definition, whether you're applying any predicates in your select from the view, and whether those predicates can be pushed down (will depend on the view definition), this could have a noticeable effect on performance.

-Mark

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Mark J. Bobak
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-----Original Message-----

From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Joe Armstrong-Champ Sent: Monday, July 02, 2007 11:35 AM
To: ORACLE-L
Subject: more on 'high cpu...'

I'm still doing the traces but in the meantime I thought I'd ask a follow up question. The query is selecting from a view. The view returns hundreds of rows relatively quickly. The query itself is selecting DISTINCT rows from the view. When I take out the distinct it returns almost instantaneously. With the distinct in it takes 40 - 50 secs. Does this ring a bell with anyone?

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http://www.freelists.org/webpage/oracle-l Received on Mon Jul 02 2007 - 11:27:23 CDT