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Message Posted: Fri, 19 Apr 2002 @ 16:43:32 GMT


     
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Subj:   Re: Nulls in a composite Primary Key deployed as a Primary Index
 
From:   John K. Wight

Clay makes a good point. Even though modeling says that any PK is (by default) NOT NULL, in reality that is not always the case. We all know that you can have NULLS in PI's in Teradata but that can come back to bite you if you have to many ins some cases. A key point with using other values is that these values have a meaning and that has to be dealt with every time access is done. So, if you are accessing via the composite key on the table, you have to qualify with either the 'default value or NULL for that column is you want to be selection the way you intend. Myself, I always stay away from values like 9999.

REMEMBER - PK <> PI's in Teradata.



     
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