RE: UncompBkts: what is it? (reference to 10053 trace)
- From: Wolfgang Breitling <breitliw@xxxxxxxxxxxxx>
- To: oracle-l@xxxxxxxxxxxxx,
- Date: Fri, 28 Jul 2006 17:35:42 -0600
Hi all,
through private conversation I was alerted to a mistake in my statement below:
UncompBkts in an Oracle 10.2 10053 trace for a frequency histogram is
(most likely) not equal to the number of rows of the table, but equal
to the number of rows with a not null value of the column.
I frequently forget this detail because in the databases I deal with
(Peoplesoft) almost all columns - ALL on which you'd ever want to
gather a histogram - are declared as not null and thus the values of
the two definitions are identical.
At 10:32 AM 7/28/2006, Wolfgang Breitling wrote:
For frequency histograms (Histogram: Freq), UncompBkts is identical to the
number of rows of the table and EndPtVals is identical to the number
of buckets
- and the number of distinct values of the column.
Quoting "Schultz, Charles" <sac@xxxxxxxxxxxxx>:
//www.freelists.org/webpage/oracle-l
Regards
Wolfgang Breitling
Centrex Consulting Corporation
http://www.centrexcc.com
--
//www.freelists.org/webpage/oracle-l
Other related posts:
