RE: Performance problem in view joining UNION ALL three tables

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 9 Jul 2014 02:47:31 +0000
Message-ID: <CE70217733273F49A8A162EE074F64D901E01323_at_exmbx05.thus.corp>


I loved the cleft stick that Oracle Marketing got caught in with partition views vs. partitioned tables.

Sales pitch on partition views (7.0):
really great - one object in SQL but the optimizer can give you the best plan for each table in the view.

Sales pitch on partition tables (8.0)
really great - you don't have to wait for the optimizer to work out a different plan for each partition

Yes, partitioned tables are really great because they eliminate the really great benefit that you got from partition views.

Regards
Jonathan Lewis
http://jonathanlewis.wordpress.com
_at_jloracle



From: oracle-l-bounce_at_freelists.org [oracle-l-bounce_at_freelists.org] on behalf of Tim Gorman [tim_at_evdbt.com] Sent: 09 July 2014 02:47
To: oracle-l_at_freelists.org
Subject: Re: Performance problem in view joining UNION ALL three tables

I had half of a chapter in our 1998 book "Oracle8 Data Warehousing" (John Wiley & Sons) devoted to partitioned UNION-ALL views, and as an Oracle employee at the time, the book was subject to review by Oracle. The reviewer excised every word on PVs, declaring that the (then-new) partitioning option in Oracle8 made PVs completely irrelevant. Gary and I fought like hell to keep something, but the Oracle reviewer would not budge a millimeter.

The script I shared earlier came originally from that book project, and I've used it on each subsequent version of the RDBMS to determine if the feature was finally removed.

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Received on Wed Jul 09 2014 - 04:47:31 CEST

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