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I hadn't looked very closely at the dbms_xplan output since I still prefer my own format, but I did a quick check on 9.2.0.3 on W2000. In the absence of system stats, I got the 'cpu costing not active' warning, and when I created some system stats, the warning disappeared.
A couple of points:
do a query against sys.aux_stats$
to check the value of the stats, if
sreadtim or mreadtim is -1, then the
statistics will not be used. You may
have collected over a period that did
no file system request for one or other
type of read.
remember that cursor are not invalidated (at least, on some versions) when you collect stats, so try doing a flush shared_pool before running explain plan so that you get new hard parse.
-- Regards Jonathan Lewis http://www.jlcomp.demon.co.uk The educated person is not the person who can answer the questions, but the person who can question the answers -- T. Schick Jr One-day tutorials: http://www.jlcomp.demon.co.uk/tutorial.htmlReceived on Thu Oct 09 2003 - 13:32:24 CDT
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