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From: John Hurley <hurleyjo...@yahoo.com>
Newsgroups: comp.databases.oracle.server
Subject: Re: DBMS_STATS cannot analyze clusters
Date: Fri, 8 Apr 2011 06:50:14 -0700 (PDT)
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Mladen:

# I have 3 tables which are always queried together and joined on the
same key. The common wisdom tells me that an index cluster is adequate
for such situation. The performance of the application did improve as
a result. The problem is with analyzing the cluster. DBMS_STATS cannot
do that:

I think the phrase "common wisdom" involving creating a cluster is
stretching it a bit.  I have been around the block quite a while and
believe me clusters are pretty uncommon.  Some authors talk about
using them and do recommend them for certain situations but in the
universe of people designing custom systems ... not often considered
AFAIK.

There is a whole set of history involving stats on clusters that for
the most part I am only vaguely aware of.  It is probably release
dependent how well dbms_stats works with clusters and may also have
some issues with stats in parallel?

Do you have any monitoring in place that looks for objects that have
old statistics?  Depending on the philosophy that you have in place
for when and if stats are gathered ( or not ) some tweaks to the
monitoring and exception reporting process could be looked at.