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Home -> Community -> Mailing Lists -> Oracle-L -> Re: RE: query slow in 9i, but not slow in 8i
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I am unfortunately speaking from heresay, however I heard once that having histograms all over the place can slow down parsing as they have to be inspected. I was left with the impression that unless the data is skewed enough to warrant a histogram then there actually is a negative cost associated with having too many histograms.
Surely someone on this list can either support me or shoot me down on this one?
Wolfgang Breitling
<breitliw_at_centrexc To: oracle-l_at_freelists.org
c.com> cc:
Sent by: Subject: Re: RE: query slow in 9i, but not slow in 8i
oracle-l-bounce_at_fr
eelists.org
02/03/2004 12:04
Please respond to
oracle-l
As long as it works for you - nothing.
However - to quote myself:
"Histograms are like drugs – An overdose [of histograms] can kill
[performance]."
And like drugs, the practice may seem harmless and you get used to it, until one day ...
"It seems easier just to ..." is never a good enough reason for me to do - or not do - something.
At 04:14 PM 3/1/2004, you wrote:
>If you have the window and use monitoring what is wrong with getting
>histograms on every table? I'm doing all new development with new queries
>getting developed everyday. It seems easier just to put histograms on
>everything. I have the window to do this overnight and will have it when
we
>go live?
Wolfgang Breitling
Oracle7, 8, 8i, 9i OCP DBA
Centrex Consulting Corporation
http://www.centrexcc.com
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Mon Mar 01 2004 - 22:11:28 CST
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