Re: Separate foreign keys with shared ID space
From: Daniel Morgan <damorgan_at_x.washington.edu>
Date: Sun, 01 Aug 2004 22:38:56 -0700
Message-ID: <1091425170.391131_at_yasure>
>
> news:410affcf$1_at_post.usenet.com...
>
>
>
> Because most real-world look-like keys do not live up to the strict
> requirements of the primary keys in a database. They are too often
> nullable or non-unique. Person identification numbers such as SSN
> are a good example of both.
Date: Sun, 01 Aug 2004 22:38:56 -0700
Message-ID: <1091425170.391131_at_yasure>
> Marshall Spight (mspight_at_dnai.com) writes:
>
>>"Christian Antognini" <christian.antognini_at_trivadis.com> wrote in message
>
> news:410affcf$1_at_post.usenet.com...
>
>>>A PK should have no business meaning. >> >>Says who? Can you justify this statement?
>
>
> Because most real-world look-like keys do not live up to the strict
> requirements of the primary keys in a database. They are too often
> nullable or non-unique. Person identification numbers such as SSN
> are a good example of both.
-- Daniel A. Morgan University of Washington damorgan_at_x.washington.edu (replace 'x' with 'u' to respond)Received on Mon Aug 02 2004 - 07:38:56 CEST