On Tue, 2010-09-21 at 15:55 +0200, Michał Frynas wrote: > I have following problem. I'm developing a new ontology handling > profile data. One of the attributes the profile contains is its icon. > I'm trying to reuse some parts of existing Nepomuk ontologies, and > that's why I'd like to utilize one of nfo:Icon or nfo:Image classes. > I've written following description:
> mpo:hasIcon a rdf:Property ; > rdfs:label "hasIcon" ; > rdfs:comment "Reference to the icon assocciated with current > profile" ; > nrl:maxCardinality 1 ; > rdfs:domain mpo:Profile ; > rdfs:range nfo:Image . > > After uploading my ontology, I import a ttl file having following > dataset: > > <MyCar> a mpo:Profile ; > mpo:name "Car" ; > mpo:hasIcon "urn:uuid:981e3c86-b0be-e38c-f224-cc2dce8810c5" ; > mpo:xpos 10 ; > mpo:ypos 12 . Because the rdfs:range of your mpo:hasIcon is a resource (nfo:Image) you must use <urn> instead of "urn" like what your TTL snippet has atm. You can also use [] for anonymous blank node. For example: <MyCar> a mpo:Profile ; mpo:name "Car" ; mpo:hasIcon [ a nfo:Image ; nie:title 'Icon for Car'; etc ] ; mpo:xpos 10 ; mpo:ypos 12 . But if you want to set <MyCar>'s icon to a resource that exists already in the RDF store, for example because tracker-miner-fs has made a resource for it (because it's a file), then you can do something like this with a SPARQL INSERT query: INSERT { <MyCar> a mpo:Profile ; mpo:name "Car" ; mpo:hasIcon ?icon ; mpo:xpos 10 ; mpo:ypos 12 . } WHERE { ?icon nie:url 'file:///usr/share/pixmaps/caricon.png' } > where mpo:hasIcon is the Image Id i've received using that query: > select ?s { ?s a nfo:Image .} > And now, when I try to get my data using following query, I get > nothing: select ?s ?t { ?s a mpo:Profile; mpo:hasIcon ?t . } > Maybe someone knows what is wrong with it. Use <urn> instead of "urn", but you of course need to create the nfo:Image first unless you use anonymous blank nodes as I explained earlier. > Is that ID urn:uuid:981e3c86-b0be-e38c-f224-cc2dce8810c5 a correct ID > of nfo:Image? We can't know, your sample isn't complete. But it looks like the subject created for an anonymous blank node. For example a file on the FS. Cheers, Philip -- Philip Van Hoof freelance software developer Codeminded BVBA - http://codeminded.be _______________________________________________ tracker-list mailing list tracker-list@gnome.org http://mail.gnome.org/mailman/listinfo/tracker-list