"Billy Verreynne" <vslabs_at_onwe.co.za> wrote in message news:<9svron$3sf$1_at_ctb-nnrp2.saix.net>...
> Are constraints (especially foreign key constraints vs. indexes) a good or bad
> idea in data warehousing?
>
> Or does this come down to a purist vs. non-purist view?
Foreign key constraints are absolutely must in data warehousing.
Usually you're using star schema there and client application is using
child-parent relationships to access your data. You need to have
warranted consistency between parents and childs, because if parent
table lacks some records from child table you can easily get no
errors, but weird results.
I've spent a lot of time trying to get proper results when some data
in datawarehouse were nonconsistent. Is very funny when you try to
find ten dollars difference in billion values. :-(
--
_________________________________________
Dusan Bolek, Ing.
Oracle team leader
Note: pagesflames_at_usa.net has been cancelled due to changes (maybe we
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Received on Thu Nov 15 2001 - 08:50:26 CST
