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Message Posted: Fri, 27 Jun 2003 @ 23:08:08 GMT

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False. I don't know how useful that would be since it's a bit unusual for it to be worthwhile to collect stats on every single column in a table.

What's new with stats in V2R5 is the ability to collect stats on a group of columns that do not constitute an index. This is a particulary good idea when a table is frequently joined on a group of columns that do not constitute an index. By collecting statistics on this group of columns, you tell the optimizer EXACTLY how many distinct values there are. This figure is needed to make accurate join cardinality estimates. ("Join Cardinality" is a fancy term for the answer to the question, "How many rows do I get when I join these two tables?")

Jon

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