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Home -> Community -> Mailing Lists -> Oracle-L -> Re: VLDBA's: gather stats on a large table
Hi Mark,
>From what I heard up to now it looks that the
optimizer does not know exactly the partition
operating on, maybe due to the binds or complex
predicates.
This mean only global statistics on
tables/indexes/columns will be used by optimizer.
I agree with Connor about setting statistics if needed.
But, I will first check do you need to maintain
statistics at all after once gathered.
The question is: do you need at all to collect
statistics again?
If you do not have SQL's using partition statistics and global statistics are representing correct future data usage (like you are dropping one partition and creating another, but data will be similar) then no need to do global statistics again.
The main thing here is to get the global statistics at the time when the data distribution will be the best for your SQL's to perform the best way.
If some are performing bad, then let fixed them by using Wolfgang Breitling method tuning by cardinality, so you can set statistics as Connor suggested or do some additional bad SQL specific statistics gathering.
Regards,
Zoran
-- http://www.freelists.org/webpage/oracle-lReceived on Tue Apr 12 2005 - 09:10:41 CDT
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