On 28 Aug 2010, at 17:37, Graham Matthews wrote:
> Hi
>
> I have a couple of questions about the semantics of some unusual SPARQL
> queries.
>
> What is the semantics of the following SPARQL query?
>
> select $x from graph_iri
> where
> {
> $x a some_iri_1.
> some_iri_2 some_iri_3 some_iri_4
> }
>
> where all of the some_iri_i's are distinct, and the graph contains NO triples
> of the form
>
> some_iri_2 some_iri_3 some_iri_4
>
> ?
>
> Is the answer empty
yes. Basic graph patterns are always matched against the active graph in their
entirety.
> or all $x's that satisfy the first triple?
>
> Similarly what is the semantics of the following query?
>
> select $x from graph_iri
> where
> {
> $x a some_iri_1.
> $y some_iri_3 some_iri_4
> }
>
> where all of the some_iri_i's are distinct, and the graph contains NO triples
> that match the second
> pattern?
likewise.
>
> thanks
> graham
>
HTH,
Axel
>
>
>
>
