Re: Artificial Primary keys
From: Henry Feinman <Henry.Feinman_at_cogeco.ca>
Date: Tue, 29 Jan 2002 17:53:14 -0500
Message-ID: <3C5727DA.3060708_at_cogeco.ca>
DNA - What about identical twins?
Fingerprints - there is no way of authoritatively converting these into a data type that can support query and enforce uniqueness (at least there wasn't 4 years ago when the vendor on the site visit said 'pay no attention to the man behind the curtain!')
Regards, Henry
--CELKO-- wrote:
Received on Tue Jan 29 2002 - 23:53:14 CET
Date: Tue, 29 Jan 2002 17:53:14 -0500
Message-ID: <3C5727DA.3060708_at_cogeco.ca>
DNA - What about identical twins?
Fingerprints - there is no way of authoritatively converting these into a data type that can support query and enforce uniqueness (at least there wasn't 4 years ago when the vendor on the site visit said 'pay no attention to the man behind the curtain!')
Regards, Henry
--CELKO-- wrote:
Or could you give an example - that is: of a natural key that holdsinformation, but is immutable? <<
DNA.
But we settled for fingerprints when I worked for the prison system
decades ago.
Received on Tue Jan 29 2002 - 23:53:14 CET