- From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
- Date: Thu, 10 Jul 2014 06:59:54 -0700
- To: public-rdf-shapes@w3.org
> From: Arthur Ryman <ryman@ca.ibm.com> > Date: Thu, 3 Jul 2014 10:58:24 -0400 > To: "public-rdf-shapes@w3.org" <public-rdf-shapes@w3.org> > Message-ID: <OFF14B15B5.802B33E2-ON85257D0A.004C62E1-85257D0A.005240FE@ca.ibm.com> > > I'd like to back up a little and discuss the need for something other than > OWL and SPARQL. > > As has been mentioned, OWL was not intended for validation. Both OWL and > RDFS are intended to infer new triples from a given set of triples. OWL > also has the characteristic that in some cases a reasoner will determine > that a set of triples is inconsistent. For example, x owl:differentThan x > is always inconsistent. At first glance this looks like a way to do > constraint checking. Unfortunately, an OWL reasoner will go to great > lengths to infer triples in order to make a given set of triples > consistent. You can't easily use OWL to even do cardinality checking. For > example, suppose you assert that :hasFather is a functional property, and > you have the triples :Luke :hasFather :Anakin and :Luke :hasFather :Darth. > An OWL reasoner will invoke the Non-Unique Naming Assumption to infer that > :Anakin owl:sameAs :Darth. > > Several years ago Evren Siren et al proposed an alternate semantics for > OWL (using CWA) so that it could be used for integrity constraint (IC) > checking and this is implemented in the Stardog database. This is actually quite easy to describe, and can be done quite efficiently. It reuses the OWL semantics for all the basic notions. > However, this > OWL IC semantics was never submitted to a standards organization. This gap > motivated us at Open Services for Lifecycle Collaboration (OSLC) to > propose the Shapes specification several years ago. It was recently > submitted to W3C. > > IMHO, it would be somewhat confusing to have two completely different > semantics for OWL. I don't think so. You are using the same semantics by and large, but instead of inferencing you are checking. > > [...] > > Regards, > ___________________________________________________________________________ > Arthur Ryman, PhD > > Chief Data Officer, Rational > Chief Architect, Portfolio & Strategy Management > Distinguished Engineer | Master Inventor | Academy of Technology > > Toronto Lab | +1-905-413-3077 (office) | +1-416-939-5063 (mobile) > peter
Received on Thursday, 10 July 2014 14:00:25 UTC