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Archives of the TeradataForum
Message Posted: Fri, 15 Jun 2012 @ 15:06:50 GMT
Subj: | | Re: Index Best Practices for Dimension Model Data? |
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From: | | Anderson, Dirk |
Teradata has a "star join" optimization, which is essentially to first cross-join all dimension tables together, and then join the result to
the fact table through the primary index on the fact table.
This can minimize data redistribution of the larger fact table. For this to work, the primary index of the large fact table must be a composite
of the primary index columns of all of the dimension tables (Region_ID, Product_Dim_Id, etc.)
Thanks.
Dirk Anderson
SVP, Manager of Architecture & Strategy
Chief Data Officer Organization
Bank of America
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