Re: How to ensure data consistency?

"Dan" <guntermann_at_verizon.com> wrote in message news:vBw%c.6339$BQ4.1607_at_trnddc06...

> Look up Celko's recent posts in this newsgroup for a demonstration on how
to
> enforce mutual exclusivity in a generalization/specialization hierarchy or
> lattice. He uses a "discriminator" value appended to the natural key to
> form an alternative key. Each specialization table will reference this
key
> and should have a constraint limiting the value of the discrimator to a
> single value. His example relates to specializations on types of cars
(SUV,
> sedan, etc.).

Excellent!

 I had a dim memory of such a post from Joe, but I had forgottne the details. Glad you provided this, Dan.

Is there any Google search that the OP can do that will lead him to the Celko answer? Received on Wed Sep 08 2004 - 20:31:29 CEST