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Message Posted: Thu, 03 May 2012 @ 10:18:25 GMT
Subj: | | Redistribution when doing RANK() OVER on PI |
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From: | | Anomy Anom |
<-- Anonymously Posted: Wednesday, May 02, 2012 09:17 -->
I was wondering why the following SELECT SQL will cause redistribution on the all-AMPs STAT FUNCTION Step?
I'm using the Primary Index (only) in the OLAP function, so all the data needed to to the ranking is already present on any given Amp (BTW -
when I remove the OLAP function from the Query, the redistribution goes away).
SELECT
RANK() OVER ( PARTITION BY PI_Column ORDER BY PI_Column )
,PI_Column
,ColumnA
,ColumnB
FROM
MyTable;
(There is a NUPI on PI_Column on MyTable)
Thanks!
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