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Message Posted: Fri, 07 Aug 2004 @ 01:06:29 GMT
Subj: | | Re: Ragarding the statistics |
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From: | | Terry Stover |
The optimizer will pull a statistics sample from one amp if no statistics exist. That random sample may not be representative of your data if
it's a small table, or if the data distribution is skewed. If the sample is representative then your plan won't change. A thumbrule is to
collect stats on all indexes and all the individual columns within the indexes. Also collect stats on known join and filter columns.
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