- From: Birte Glimm <birte.glimm@comlab.ox.ac.uk>
- Date: Thu, 16 Sep 2010 11:55:25 +0100
- To: Olivier Corby <olivier.corby@sophia.inria.fr>
- Cc: SPARQL Working Group <public-rdf-dawg@w3.org>
On 16 September 2010 07:01, Olivier Corby <olivier.corby@sophia.inria.fr> wrote: > Before writing my review on entailment, I have a question on this point: > > > section 2.4 Boolean Queries (Informative) > > The two conditions C1 and C2 also have an effect on the answers to Boolean > queries. For Boolean queries that contain variables, e.g., > > ASK { ?x a rdf:Property } > > The query answer is yes (true) if there is at least one solution mapping > (i.e., a solution that satisfies also conditions C1 and C2) and it is no > (false) otherwise. For example, if the queried graph is the empty graph, the > query has no solution since even if a pattern instance mapping yields an > axiomatic triple, condition C2 cannot be satisfied. > > My question is why condition C2 cannot be satisfied ? Good question indeed. The example is wrong. I think I did not take into account that not only the rdf:_1, rdf:_2, ... replaced for ?x lead to an entailed triples, but we also have rdf:type rdf:type rdf:Property . ... C2 only prohibits the infinitely many rdf:_1, rdf:_2, ... , but not rdf:type for example. Maybe we just remove that example? Birte > Thanx, > > Olivier > > > > -- Dr. Birte Glimm, Room 309 Computing Laboratory Parks Road Oxford OX1 3QD United Kingdom +44 (0)1865 283520
Received on Thursday, 16 September 2010 10:55:53 UTC