Re: what data models cant do

"mountain man" <hobbit_at_southern_seaweed.com.op> wrote in message news:<USohe.2729$E7.1492_at_news-server.bigpond.net.au>...

> I have been looking around for an article in which I had seen a similar
> treatment of "derivations" since you posted the above, and this evening
> found it again. You may already have seen this one:
>
> What data models cant do --- David Hay
> http://www.essentialstrategies.com/publications/businessrules/brules.htm

A rather old article.

> In summary, the article details at least four categories of things not
> adequately described in data models:
>
> 1) implied assumptions
> 2) when optional relationships are activated
> 3) how to keep multiple paths between entities
> 4) derivations [derived data --- see above]

The article's title is rather misleading. It should be called: "What Barker's diagrams can't do."

Logical data models can do all that.

Regards Received on Sun May 15 2005 - 07:19:19 CDT