I haven't checked it yet, but 9.2 has init.ora
parameters and hints to allow dynamic_sampling
of statistics. (9.0 has a couple of events that can
be set to do the same, but I don't think they exist
in 8.1.7). This may help with GTTs.
--
Jonathan Lewis
http://www.jlcomp.demon.co.uk
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Connor McDonald wrote in message <3D04F373.7C40_at_yahoo.com>...
>Paul Drake wrote:
>> How are you handling the subject of statistics for global temporary
>> tables where the average number of rows for such tables varies widely?
>>
>
>In the (few) cases I've used them, I've stolen a technique from Tom Kyte
>and used dbms_stats to set them directly. Hardly ideal, but in most
>cases I would propose that people at least know the number of rows in
>the gtt since you've got to have code to populate it (eg insert into
>gtt select ..., and then using sql%rowcount). For other stats, such as
>column level cardinality a 'guestimate' should suffice.
>
Received on Tue Jun 11 2002 - 09:17:32 CDT
