Re: So let me get this right: (Was: NFNF vs 1NF ...)

paul c wrote:
>> One doesn't have to go outside classic relational model in order to
>> approach transitive closure. I could suggest only a glimpse of a
>> theory here, but the idea is to watch the analogy with matrix
>> algebra. ...

> 
> thanks, i'll ponder it.  (i suppose the implication is that RVA's may
>  not be necessary?)

I think what I've had a problem understanding is that whilst the relations are based on first-order logic, that doesn't mean that the query language used to interrogate the relations has to be first-order as well.

So you can have second-order expressions in the query language that are just used to transform one set of first-order predicates into another first-order predicate.

Paul. Received on Fri Feb 11 2005 - 11:29:25 CET