Re: Use of numeric pseudo-key vs. text key

Srinivas Venigalla wrote:
>
> There is a plenty of discussion in this group on this topic. you may want to
> search using a good search engine like google. But here is my two cents
> worth:
>
> A primary key must be part of the data the table is representing. Good
> examples of a Primary key are: Emp_ID, Product_ID, SS_NO, tel_no, etc. They
> are naturally unique keys within the enterprise or the domain.
[snip]

Beware of the pitfalls of those "naturally unique" keys. Some of them tend to be not unique! E.g. the SS_NO you mentioned: The authorities succeed in assigning the SAME SS_NO to different individuals every now and then. And then you're really screwed if you've designed your database with the SS_NO as PK.

Regards,
Heinz Received on Mon Apr 02 2001 - 09:02:01 CEST