- From: conor dowling <conor@the325project.org>
- Date: Mon, 9 May 2005 10:25:00 -0700
- To: Jeen Broekstra <jeen@aduna.biz>
- Cc: semantic-web@w3.org
first off, thx very much for the info Jeen. One last question on "rdf:about" or rather the value of "?subject" ... > >> 2) rdf:about value and value of "?subject" >> # can I get the "rdf:about" from every resource >> PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> >> SELECT ?subject >> WHERE { ?subject rdf:about ?about } > > No. > > rdf:about is not an actual property, but is simply a bit of syntax in > the RDF/XML serialization that is used to denote the subject of a > triple. It does not occur in the RDF graph and can not be queried > through SPARQL (or any other RDF query language that I know of). but is the value returned in ?subject is equivalent to rdf:about in RDF/XML? SELECT ?subject Let's say I assign it to a variable "subjectIdentifier". Then can I say ... SELECT ?name WHERE {subjectIdentifier dc:title ?name} (assuming of course that dc:title is supported by that subject ...). In other words, can I use the subject id's across queries to that data source? Is the subject id data source dependent, nothing more than a convenient resource identifier for use within that data source? > >> is this equivalent to (presuming all resources have abouts and aren't >> blank)? >> SELECT ?subject >> The subject variable is bound to an about uri value OR if blank, a >> unique id, scoped to the result. Is that right? > > Not quite. See above. > # can I get the "rdf:about" from every resource >> PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> >> SELECT ?about >> WHERE { ?subject rdf:about ?about } >> >> WHERE { ?subject rdf:about ?about }
Received on Monday, 9 May 2005 17:25:52 UTC