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Home -> Community -> Mailing Lists -> Oracle-L -> Re: segment monitoring, stats, histograms
As Jonathan so diplomatically said in a post in this list "most of the
time it doesn't do any harm". The question that always comes to my mind is
is it necessary, i.e. would any plans go bad if you DIDN'T analyze?
My conjecture, of course, is that few, if any, would.
Of course that is a philisophical question. If your current practice isn't causing any trouble you don't change it just to find out if a different practice would, or not, cause any trouble. I wouldn't do that either.
Mercadante, Thomas F wrote:
> Jeremiah,
>
> I have all tables in monitoring mode. And I gather stats daily using the
> USER_TAB_MODIFICATIONS table. Granted that I have mostly OLTP databases,
> but I have not yet run into a situation where the execution plan changed to
> something bad because of new stats being gathered. Monitoring has not
> impacted DML operations. And we perform a full stats gather - I never
> sample. I don't gather histogram stats as I have not had the need yet.
>
> Runs fine for us.
>
-- Regards Wolfgang Breitling Centrex Consulting Corporation www.centrexcc.com -- http://www.freelists.org/webpage/oracle-lReceived on Fri Feb 04 2005 - 09:47:08 CST