Re: Entailment Doc ready for review

On 16 September 2010 07:01, Olivier Corby <> 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?


> Thanx,
> Olivier

Dr. Birte Glimm, Room 309
Computing Laboratory
Parks Road
United Kingdom
+44 (0)1865 283520

Received on Thursday, 16 September 2010 10:55:53 UTC