Re: PLAN_HASH_VALUE in v$sql ?

From: Jonathan Lewis <jonathan_at_jlcomp.demon.co.uk>
Date: Fri, 5 Mar 2004 07:41:09 -0000
Message-ID: <003001c40285$39d3e330$7002a8c0@Primary>

select plan_hash_value, count(*)
from v$sql
group by plan_hash_value;

If you have a very large number of statements with the same plan_hash_value, they may be the "same" statement with different literal values - i.e. candidates for bind variables.

Regards

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

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Original Message ----- From: "Dilip Chavan" <dilipc_at_gtllimited.com> To: <oracle-l_at_freelists.org> Sent: Friday, March 05, 2004 7:02 AM Subject: PLAN_HASH_VALUE in v$sql ?

: Hi List,
:
: Just read from the documentation that PLAN_HASH_VALUE column (Hash value
: built on the execution plan) in the v$Sql is used to link V$SQL_PLAN view.
:
: But when I see in the database, normal HASH_VALUE column has been used to
: link these two views. Is there anything wrong here ?
:
: If HASH_VALUE column is used to link these views, then what is the use of
: PLAN_HASH_VALUE in v$sql ?
:
:
: Thanks,
: ~Dilip
:
:
:
:
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Received on Fri Mar 05 2004 - 01:40:10 CST