Re: system statistics

Jonathan Lewis wrote:

>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
>
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>The Co-operative Oracle Users' FAQ
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>
>
>

Thanks. I'll beat it up some more and try again.

-- 
Daniel Morgan
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