- From: Andy Seaborne <andy.seaborne@epimorphics.com>
- Date: Tue, 27 Sep 2011 15:13:40 +0100
- To: public-rdf-dawg@w3.org
One possibility is to define SERVICE algebra over the preceding pattern:
{ ?s ?p ?g .
SERVICE ?g { ?s1 ?p1 ?o1 }
?s2 ?p2 ?o2 .
}
===>
(join
(service ?g (bgp (?s1 ?p1 ?o1))
(bgp (?s ?p ?g)))
(?s2 ?p2 ?o2))
which puts a defined ?g into the service operation because the
"?s ?p ?g" is evaluted - then service part done.
c.f. FILTER
which works over a subpattern
c.f. OPTIONAL.
which combines the preceding pattern and the {} part into one operation.
Andy
Received on Tuesday, 27 September 2011 14:14:20 UTC