- From: Birte Glimm <birte.glimm@comlab.ox.ac.uk>
- Date: Tue, 6 Oct 2009 14:09:24 +0100
- To: "Seaborne, Andy" <andy.seaborne@hp.com>
- Cc: SPARQL WG <public-rdf-dawg@w3.org>
[snip] >> > Under simple entailment matching there is one because "P(BGP) is a >> subgraph of G" and not an entailment relationship, and ?x=_:x. (DAWG did >> try for an entailment relationship but the cardinality issues were a >> problem.) >> > >> Yes, we need a similar condition for entailment regimes but not based >> on pure subgraph matching. >> >> For now we have this as an open problem and how queries over different >> named graphs should behave (do we take entailments into account that >> depend on triples from different named graphs). I'll try and add notes >> for these two issues in the ent. regimes doc. I have added notes for this issue and for the named graphs issue that Steve mentioned to the doc, so we can't forget them. I hope I have some time during the flight/at the airport to think about how we can best handle this. Birte >> Just to see whether I get simple entailment right. If you have >> :s :p :o >> and query with BGP >> ?x :p :o >> you would only get ?x=:s and not ?x=_:x for some blank node _:x, >> right? I mean you have the RDF simple entailment rules se1 and se2 >> (http://www.w3.org/TR/rdf-mt/#simpleRules), which could be used to add >> _:x :p :o with se2, but you do not use that, right? For simple >> entailment one just has to check sub-graphs of the queried graph. > > That's my reading. That's what the "sub-graph" brings. > > Andy > >> >> Birte >> >> >> >> > Andy >> > >> > >> >> >> >> -- >> Dr. Birte Glimm, Room 306 >> Computing Laboratory >> Parks Road >> Oxford >> OX1 3QD >> United Kingdom >> +44 (0)1865 283529 > -- Dr. Birte Glimm, Room 306 Computing Laboratory Parks Road Oxford OX1 3QD United Kingdom +44 (0)1865 283529
Received on Tuesday, 6 October 2009 13:10:00 UTC