RE: query performance - getting started
Date: Thu, 7 Apr 2011 15:34:51 -0400
Message-ID: <C95D75DD2E01DD4D81124D104D317ACA16155779B1_at_JAXMSG01.crowley.com>
Thanks to some comments by Ellis Miller, I will be upgrading one of my databases to 11g and investigation the results cache feature as it might prove to be viable.
Joel Patterson
Database Administrator
904 727-2546
From: Jorgensen, Finn [mailto:Finn.Jorgensen_at_constellation.com] Sent: Thursday, April 07, 2011 1:48 PM
To: Patterson, Joel; 'oracle-l_at_freelists.org' Subject: RE: query performance - getting started
Last time I looked into MV refreshes (in 10gR2) they did not do truncates. They do a delete of all rows. I assume this is so running queries aren't interrupted by the refresh.
So, if you have the luxury of doing a truncate and then insert (append) or better yet, drop table and CTAS, and the table is large, then that would be faster.
Thanks,
Finn
From: oracle-l-bounce_at_freelists.org [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Joel.Patterson_at_crowley.com
Sent: Thursday, April 07, 2011 8:51 AM
To: Joel.Patterson_at_crowley.com; oracle-l_at_freelists.org
Cc: kylelf_at_gmail.com
Subject: RE: query performance - getting started
Query performance continued.
We have a very complicated Materialized view, and a view that utilizes the MV. We cannot use Fast refresh - a complete refresh is necessary. The app can decide when the view is refreshed, and can execute dbms_refresh when necessary.
Essentially all records are truncated, and the view is rebuilt as part of the complete refresh. So, is this just as easy, efficient as any other method such as Temp tables, Truncating a permanent table and re-inserting, or other?
Moving forward,
JP
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-- http://www.freelists.org/webpage/oracle-lReceived on Thu Apr 07 2011 - 14:34:51 CDT