- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Tue, 20 Sep 2005 14:31:40 +0100
- To: Bijan Parsia <bparsia@isr.umd.edu>
- CC: Dan Connolly <connolly@w3.org>, Enrico Franconi <franconi@inf.unibz.it>, Pat Hayes <phayes@ihmc.us>, RDF Data Access Working Group <public-rdf-dawg@w3.org>
Bijan Parsia wrote: > On Sep 20, 2005, at 7:04 AM, Dan Connolly wrote: > [snip] > >>Enrico, elsewhere in your message about "Adoption of entailment in >>SPARQL" >>of September 19, 2005 11:55:09 PM GMT+01:00, you wrote "here we don't >>argue whether this is useful and how this is going to be used." Note >>that I >>pretty much stopped reading at that point. > > > I think you were mislead by Enrico's words there. There are plenty of > places in that note that he appeals to existing, documented SPARQL use > cases to motivate his technical points, e.g., > > """ON REDUNDANCY OF TOLD BNODES IN ANSWERS > [issue <http://www.w3.org/2001/sw/DataAccess/issues#rdfSemantics>] > > """ > Should queries of non-lean and lean graphs that entail each other > give the same answers? > """ > > The answer to this question should be *yes*. See use case 1, > "Publishing on the Web", in > <http://lists.w3.org/Archives/Public/public-rdf-dawg/2005JulSep/0430>). > This is also relevant, as noted by PFPS, to enable interoperability > between different interoperating implementations of RDF.""" The quoted email has two use cases - the same query is used on the same data in two separate situations. The desired results are then different. I can't tell if the proposed formulation reflects this or not - at the moment, I don't see any place where this is acknowledged. Could someone kindly point such a place out to me, please? Andy > > >>I'll be more motivated to study the technical >>details when I know which user requirements, use cases, and >>applications >>a proposal is intended to address and which it's not intended to >>address.\ > > [snip] > Since the two major alternative approaches as I understand them > "virtual graphs" vs. entailment bases are, at least in some forms, > *equivalent* (I'm not clear pat means them to be anymore!) then the > whole first section of that email is motivate by spec clarity issues. > So, the use case *from my perspective* is producing interoperable > implementations for a variety of semantics imposed on the source > documents. For example, I may want to query the syntax of an RDF > document (i.e., with full asserted redundancy) for an editor > applicaiton, or I may want just the non-redundant information in the > graph (e.g., I don't want to have to post query filter out that someone > loving someone since mary loving john was already in there). > > Cheers, > Bijan. > >
Received on Tuesday, 20 September 2005 13:32:01 UTC