Re: OWL-cool

On 23/4/03 6:25 pm, Ian Horrocks wrote:
> I had assumed that we were talking about datatype (concrete domain) keys - the
> (archetypal) example in Bob's original email used SSN. The problem with OWL
> DL/Lite is that the set of datatype properties is disjoint from the set of
> inverse-functional properties (a deliberate design choice in order to avoid
> the complexity of keys with datatypes), so the cardinality+inverse solution
> doesn't work in this case - even if one could live with the apparent
> awkwardness of the syntax.

I completely agree with you, if we choose the datatype (concrete domain)
keys: this of course makes sense since the values for key attributes are
always datatypes -- and this is true for example for the SSN attribute.
However, even with the SSN as a key attribute, I argue that it is much
better to model such attributes as 'abstract' (i.e., non-datatype). In fact
you really dont't need to have any special predicate applied to such
attributes in the conceptual schema. Usually keys are there and you don't
want to do anything with them at the conceptual level, so making them
datatype keys is an unnecessary complication.

cheers
-- e.

Enrico Franconi                  - franconi@inf.unibz.it
Free University of Bozen-Bolzano - http://www.inf.unibz.it/~franconi/
Faculty of Computer Science      - Phone: (+39) 0471-315-642
I-39100 Bozen-Bolzano BZ, Italy  - Fax:   (+39) 0471-315-649

Received on Wednesday, 23 April 2003 13:21:04 UTC