- From: Jos De_Roo <jos.deroo@agfa.com>
- Date: Mon, 17 May 2004 22:14:22 +0200
- To: "Pat Hayes <phayes" <phayes@ihmc.us>
- Cc: Kendall Clark <kendall@monkeyfist.com>, RDF Data Access Working Group <public-rdf-dawg@w3.org>
PatH wrote: >> On Tue, May 11, 2004 at 04:52:52PM -0700, Rob Shearer wrote: >> >>> 4.6 Additional semantic knowledge >>> It should be possible for knowledge encoded in other semantic languages, >>> such as RDFS, OWL, and SWRL to affect the results of queries about RDF >>> graphs. >> >> In the interests of making progress, I'm willing to accept Rob's >> version, above, of my original proposal. In the current UC&R doc, >> my original is 4.6 and Rob's variant is 4.6a. >> >> So, I'd be willing to accept a modest reworking of 4.6a: >> >> Additional Semantic Information >> >> It should be possible for knowledged encode din other semantic >> languages -- for example: RDFS, OWL, etc. -- to affect the results of >> queries about RDF graphs. >> >> In fact, unless someone objects, I'd like to make that the language in >> the document and the version which we vote on at some point. > > Sorry to rock the boat, but this requirement worries me. It is > possible to interpret it as saying that a query-responder has a > licence to use RDFS, OWL, etc., content to respond to any RDF query. > I think that would be a very bad idea, if the query is unable to > specify which of the various languages are intended to be used. > > Moreover, the term 'semantic language' is not defined, and according A Google search for 'define:semantic' is returning results and one for 'define:language' as well, but indeed, it can't find anything for 'define:semantic language' (which is not a proof of course :)). > to some versions of what SWeb meaning boils down to, it could include > unformatted English inside rdf:comment strings. Already we have a > potential disagreement over whether SWRL counts as a semantic > language. > > I would be happier if we did not have any such requirement. It seems > to me to be orthogonal to the query language design, and a matter to > be handled by an RDFS or OWL inference engine rather than by a > querying protocol. Our charter explicitly says that the RDF graph > being queried may be 'virtual' , so it could be an RDFS or OWL > closure or the virtual graph obtainable from a given graph from a > particular SWRL rule set: this provides us with a very neat way to > avoid this issue and keep our attention focused on querying graphs > rather than drawing inferences which may or may not be valid > according to a variety of different semantic frameworks. > > Finally, the wording suggests that OWL and RDFS are 'other' than RDF, > whereas in fact they are semantic extensions of RDF. > > At the very least, it ought to be possible to do a 'bare RDF' query, > explicitly rejecting any reliance on any other non-RDF implication or > machinery, and the requirement, if we keep it, should make this clear. fully agreed > Suggestion (if we must keep this requirement): > > Additional Semantic Information > > It should be possible for a query to indicate that the answers should > take into account knowledge encoded in RDF semantic extensions, such > as RDFS, OWL, etc.. OK, I would think that this is a requirement... -- Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
Received on Monday, 17 May 2004 16:15:01 UTC