select ?x ?a ?b ?c ?d ?e ?f where {
graph ?r {
?x ?y <CountryZ>
}
graph ?r1{
?x ?y <CountryZ1>
}
?r <saidBy> Tia ;
<saidOn> ?b ;
<saidAt> ?c ;
<confidence> ?d ;
<comment> ?e .
?r1 <saidBy> Astrid.
}
Is the above query to retrieve a person who is linked to two different
countries correct?
I am just curious as to whether it is syntactically accepted by Jena
On Thu, Oct 31, 2013 at 8:45 PM, Joshua TAYLOR <[email protected]>wrote:
> On Thu, Oct 31, 2013 at 10:47 AM, Eric Scott <[email protected]> wrote:
> > You could try something like this:
> >
> > select ?a?b?c?d?e
> > where
> > {
> > ?g a :MyKindaGraph.
> > graph ?g
> >
> > {
> > ?r rdf:subject <Mr_X>.
> > ?r rdf:predicate <isPresident>.
> > ?r rdf:object <CountryZ>.
> > ?r saidBy ?a.
> > ?r saidOn ?b.
> > ?r saidAt ?c.
> > ?r confidence ?d.
> > ?r comment ?e
> > }
> > }
>
> I think, though I could be wrong, that the point wasn't just to put
> the triples _into_ a named graph, but to use a named graph to serve
> _as_ the reified triple (or triples). E.g.,
>
> graph ?g { <Mr_X> <isPresident> <CountryZ> }
> ?g saidBy ?a ; ... ; comment ?e .
>
> This avoids needing three triples for each reified statement, and
> makes the queries easier to write. It also makes it easier to provide
> meta information about a collection of triples, rather than just a
> single reified triple.
>
> //JT
> --
> Joshua Taylor, http://www.cs.rpi.edu/~tayloj/
>
