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Re: index usage on view union, with subselect

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Wed, 18 Dec 2002 19:16:00 -0000
Message-ID: <atqhid$p6d$1$8302bc10@news.demon.co.uk>


There are a couple of hints and hidden
parameters that may help - I can never
remember details of which specific Oracle version they are relevant to:

    /*+ push_pred */

pushes predicates into view.

parameters:
_PUSH_JOIN_PREDICATE = true
_PUSH_JOIN_UNION_VIEW = true

To set these with an alter session, you
need to surround the parameter with
double quote marks.

--
Regards

Jonathan Lewis
http://www.jlcomp.demon.co.uk

Coming soon a new one-day tutorial:
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____England______January 21/23


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bung ho wrote in message
<567a1b1.0212180935.24989585_at_posting.google.com>...
>"Jonathan Lewis" <jonathan_at_jlcomp.demon.co.uk> wrote in message
news:<atpg31$ckd$1$8300dec7_at_news.demon.co.uk>...

>> I like the 'nothing unusual there' line.
>>
>> Oracle has unnested a subquery, and
>> recognised a partition view - that's a
>> pretty good feat of optimisation.
>> > >you're right, of course. i guess i have come to expect magic from >oracle. >
Received on Wed Dec 18 2002 - 13:16:00 CST

Original text of this message

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