Re: Relational vs network vs hierarchic databases

"Neo" <neo55592_at_hotmail.com> wrote in message news:4b45d3ad.0411081437.12395f19_at_posting.google.com...
> > Perhaps you should try finding something that _can't_ be easily
> > modelled in a relational model, instead.
>
> How would one represent the following without redundancy or NULLs?
>
> john like mary.
> mary like john.
> (john like mary) because (mary like john).
> bob hit mary on elbow.
> john hit bob on shoulder.
> (john hit bob on shoulder) because (bob hit mary on elbow) during lunch.

See, the thing is, *representation* per se isn't that big of a problem. The trick is, what kind of manipulations do you want to be able to do? If you don't specify the problem as being relative to a particular set of manipulations, then just about anything is a good answer to "how to represent." For example, the above could be represented as a string. It's easy as pie to do so, but your subsequent manipulations are then constrained to string operations.

Marshall Received on Tue Nov 09 2004 - 02:31:21 CET