From: "Jason Kratz" <jkratz@rctanalytics.com>
Subject: oracle very slow after computing stats
Date: 2000/06/06
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We have an Oracle instance that is running considerably slower after
computing stats.  Heres the situation:  I estimated stats at 25% on all
tables in a schema (not SYS) and computed stats on all of the indexes in
that schema (primary keys, etc are all seperated out from the data into
seperate tablespaces).  At first our nightly loads ran fine.  After a day or
so of the database up and running with stats the dataloads are running
several times slower.  We had this problem before but I had only computed
stats on a few tables.  When I dropped them before everything worked fine
again.  I was under the impression that most dbs should be running with
computed stats.  Shouldnt stats help increase db performance?  Another note:
this db is highly normalized resulting in rather large joins necessary when
joins are done.  Help!!!!

Jason




