- From: Ian Horrocks <horrocks@cs.man.ac.uk>
- Date: Tue, 11 May 2004 09:42:08 +0100
- To: Jeremy Carroll <jjc@hplb.hpl.hp.com>
- Cc: "Dimitrios A. Koutsomitropoulos" <kotsomit@hpclab.ceid.upatras.gr>, www-rdf-logic@w3.org
Dimitrios, I imagine that you don't really want, e.g., the individual "John" and the data value that is John's social security number to be the same object; what you want is to be able to use data values as DB-style keys. As Jeremy points out, this is possible in OWL-Full by using inverse-functional datatype roles. In [1] you will find an analysis of the consequences of adding a more comprehensive key mechanism to description logics (there is also a technical report at [2] if you want all the gory details). As you will see, there are decidability and complexity issues, but adding keys to a DL is theoretically possible. Ian [1] http://www.cs.man.ac.uk/~horrocks/Publications/download/2003/LAHS03a.pdf [2] http://lat.inf.tu-dresden.de/~clu/papers/archive/ltcs02-04.ps.gz On May 10, Jeremy Carroll writes: > > Dimitrios A. Koutsomitropoulos wrote: > > > > > > > However, because of the consequent seperation of object and datatype > > properties, one still looses the (simple) ability to connect uniquely > > individuals and datatypes. For example,given an ID number, one can never > > retrieve the person to whom it corresponds to (using OWL DL of course, but I > > doubt if this is possible even in Full). Whould this be so hard for a DL > > reasoner to implement? > > > > It's possible in OWL Full using an InverseFunctional Datatype Property. > I share your skepticism that this is not too hard for DL ... Ian > Horrocks has argued on a number of occassions that it is, but stubbornly > I remain unconvinced that this feature is truely harder than others that > are already in OWL DL. But I can't point to working DL style reasoners ... > > Jeremy > > > > > > >
Received on Tuesday, 11 May 2004 02:43:45 UTC