- From: Bijan Parsia <bparsia@cs.man.ac.uk>
- Date: Fri, 7 Mar 2008 00:34:30 +0000
- To: Jim Hendler <hendler@cs.rpi.edu>
- Cc: Ian Horrocks <ian.horrocks@comlab.ox.ac.uk>, "Web Ontology Language ((OWL)) Working Group WG" <public-owl-wg@w3.org>
On Mar 7, 2008, at 12:27 AM, Jim Hendler wrote: > > Ahh, I misunderstood - I think we need to be very clear on this - I > think some of us were assuming that the idea of the DB fragment was > to be able to represent something close to a DB schema and use it > in processing data from the DB (a la datalog/SQL type stuff) - sort > of like expressing an E/R model and then using it to make simple > inferences over the data. Anyway, a lot of the project will be > correctly describing these fragments and their features. Actaully, DL Lite does that as well. The main issue is that there is a trade off between having subproperty heirarchies and having keys. Putting both together means you lose the logspace data complexity. Giving up the first means you lose some fairly popular RDFSness. Giving up the second means you lose some dbness. I'm hoping we can keep subobjectproperites and have inversefunctional data properties (and give up inversefunctional object properties and subdataproperites) while keeping the logspace data complexity. If we can do that, then I think we've hit a very sweet spot of expressivity and scalability. Cheers, Bijan.
Received on Friday, 7 March 2008 00:34:49 UTC