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Re: Examples of SQL anomalies?

From: -CELKO- <jcelko212_at_earthlink.net>
Date: Wed, 2 Jul 2008 08:44:05 -0700 (PDT)
Message-ID: <0496b148-f2b4-4555-a5ef-ab4ff830a7aa_at_d45g2000hsc.googlegroups.com> 






>> Once again you are introducing confusion, in this case muddying the waters with unstated design questions, confusing a system that is designed to anticipate suppliers and bills with one that isn't. <<





Do you really find that a credit balance is not a common business
practice? What I am pointing out is that a zero is a value on a scale
and a NULL or other missing value indicators is not.  Would you like
to go into Codd's A and I markers?



Instead of rudely ranting about illiteracy (while misspelling
"tomorrow"), show us how to indicate when a $0.00 payment is a credit
balance on an actual billing or a lack of a payment on a non-existent
billing.  The only thing that comes to mind is a flag of some kind
which splits the single scalar value over two or more columns in
violation of 1NF and leads to user-defined behaviors rather than
guaranteed consistent behaviors.
Received on Wed Jul 02 2008 - 17:44:05 CEST












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