Re: MV Keys
Date: 2 Mar 2006 10:59:19 -0800
Jon Heggland wrote:
> How do you define "repeating group" as opposed to "nested relation",
A repeating group is a set of attributes, all doing the same thing, but repeated to allow higher cardinality. Nested relation/RVA is a single atribute whose type is relation. An example of a repeating group is allowing up to three phone numbers for a customer by having three attributes, PhoneNumber1, PhoneNumber2, and PhoneNumber3. This approach has significant disadvantages.
Yes; that's how I'm using the terms. For some reason I prefer the "nested" term to the RVA term.
Marshall Received on Thu Mar 02 2006 - 19:59:19 CET