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Archives of the TeradataForum
Message Posted: Fri, 30 Sep 2016 @ 19:46:28 GMT
| Subj: | | Re: Expression Statistics |
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| From: | | Anomy Anom |
<-- Anonymously Posted: Friday, September 30, 2016 15:31 -->
COLLECT STATS computes the expression value for each row processed and treats it as if it were a "virtual column" in the table.
This is particularly useful for join conditions that include UDT methods, CAST, SUBSTRING, concatenation, or other scalar functions.
Just like column statistics, you don't necessarily need statistics on "all" expressions.
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