Re: Primary Key Theory Question

From: N. Shamsundar <>
Date: Mon, 29 Mar 2004 13:40:38 -0600
Message-ID: <c49u7q$2u1c$>

Don Verhagen wrote:
> In,
> Bob Hairgrove <> typed:
> : On Sun, 28 Mar 2004 18:56:03 GMT, Ben <>
> : wrote:
> :
> [Snipped...]
> SSN is *not* a good *primary* key in large personnel databases, working in
> the industrial temporary services industry, I can tell you have duplicate
> SSN's (ya know, the same guys sells the fake SSN cards to multiple people).
> Just a perspective from the employment end.

Here is another piece of information about SSNs : I work with student records at a university, and we have many students with two SSNs. When foreign students arrive, they are given an SSN beginning with 999; later, they open a bank account or get a job and obtain a "regular" SSN. It is tricky to unify/merge records with two different SSN values.

N. Shamsundar
University of Houston Received on Mon Mar 29 2004 - 21:40:38 CEST

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