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From Kristian Waagan <kristian.waa...@oracle.com>
Subject Re: Question on cardinality, statistics, and when things go stale
Date Fri, 19 Nov 2010 12:48:01 GMT
  On 18.11.10 20:27, Bergquist, Brett wrote:
> Thanks for the explanation!  So if I understand this correctly, if the indexes that I
am querying on are always unique (the computed value that is index is always unique), then
as long as the optimizer knows about these statistics (ie I have run "syscs_util.syscs_update_statistics()"
after the table has a few rows), and my query is always like "select * from table where indexval>=
'some starting value' and indexval<  'some ending value'" then it should always use the
index?

FYI, I'm working on automatic index statistics creation/update.
See DERBY-4771 if you want to provide any input.


Regards,
-- 
Kristian

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