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RE: about parallel query

From: Deshpande, Kirti <kirti.deshpande_at_verizon.com>
Date: Wed, 10 Jan 2001 19:16:12 -0600
Message-Id: <10737.126357@fatcity.com>


Hi Alex,
Even if the tables are not partitioned, PQ can be used to speed up queries. But there are other factors that must support PQ operation. Queries that benefit most from PQ are the ones doing full table scans. If the tables are spread in multiple datafiles that are on mulitiple disk drives PQ can help. But PQ will require CPU resources as well. If CPUs are not fully utilized on your system, then by all means try PQ. I am using it in a 7.3.4 database on serveral tables (non-partitioned, of course, but are spread out in multiple datafiles) with good results. There is enough information available in Oracle Concepts and Tuning Guides on Parallelism. Please review it. It will provide you all the information you need (& more). You can also try this URL for Jonathan Lewis's papers on PQ http://www.jlcomp.demon.co.uk/#Index. The information in them pertains to Oracle7 but still those are good source for understanding PQ. Parallel Servers(OPS) can use PQ, but that's not a requirement for using PQ.
Good Luck..

> -----Original Message-----
> From: Koivu, Lisa [SMTP:lkoivu_at_qode.com]
> Sent: Wednesday, January 10, 2001 2:55 PM
> To: Multiple recipients of list ORACLE-L
> Subject: RE: about parallel query
>
> Alex, are any of your tables partitioned? If they aren't, PQO may not
> benefit your queries and in fact may hinder them.
>
> Lisa Rutland Koivu
> Oracle Database Administrator
> Qode.com
> 4850 North State Road 7
> Suite G104
> Fort Lauderdale, FL 33319
>
> V: 954.484.3191, x174
> F: 954.484.2933
> C: 954.658.5849
> <http://www.qode.com>
>
> "The information contained herein does not express the opinion or position
> of Qode.com and cannot be attributed to or made binding upon Qode.com."
>
>
> -----Original Message-----
> From: Alex zhang [ <mailto:cd_toronto_at_hotmail.com>]
> Sent: Wednesday, January 10, 2001 3:42 PM
> To: Multiple recipients of list ORACLE-L
> Subject: about parallel query
>
>
> Hi,There
> We have very big table to query from. Some tables have to be joined
> together. It was a Internet application, so speed is so important
> for us. I guessed I could use parallel query to increase the query speed.
> But I know little about it. How can I use it? If it is possible
> to use parallel query and parallel server together?
Received on Wed Jan 10 2001 - 19:16:12 CST

Original text of this message

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