[Top] [All Lists]

Re: [ontolog-forum] named graphs and rdfg:subGraphOf

To: "[ontolog-forum]" <ontolog-forum@xxxxxxxxxxxxxxxx>
From: Joel Bender <jjb5@xxxxxxxxxxx>
Date: Wed, 07 Oct 2009 17:47:05 -0400
Message-id: <4ACD0C59.8090108@xxxxxxxxxxx>
Jakub,    (01)

> :f rdfg:subGraphOf :g does not hold if :f and :g are specified as follows:
> :f {
>       :a rdfs:subclassOf :c .
> }
> :g {
>       :a rdfs:subclassOf :b .
>       :b rdfs:subclassOf :c .
> }    (02)

When dealing with graphs of triples, I have found it useful to translate 
them into quads.    (03)

     :a rdfs:subClassOf :c :f .
     :a rdfs:subClassOf :b :g .
     :b rdfs:subClassOf :c :g .    (04)

Now you can run queries of (?s ?p ?o :f) and make sure they can unify 
with (?s ?p ?o :g) and you can see that there is no subgraph.  Now 
create a new graph of things that are entailed in :g, and call it...    (05)

     :a rdfs:subClassOf :c :h .    (06)

Now assert that everything in :g is also in :h, and put that fact into 
your database as well, into a graph that is reserved for these kinds of 
assertions...    (07)

     :g rdfg:subGraphOf :h :universe .    (08)

and you'll see by running the same tests that :f is a subgraph if :h.    (09)

The :universe is where I put all kinds of stuff about when jobs were 
run, who ran them, what graphs the jobs created, etc.  I've been calling 
this "provenance" information, but keeping my voice down because there's 
a chance I'm using the term incorrectly.    (010)

Joel    (011)

Message Archives: http://ontolog.cim3.net/forum/ontolog-forum/  
Config Subscr: http://ontolog.cim3.net/mailman/listinfo/ontolog-forum/  
Unsubscribe: mailto:ontolog-forum-leave@xxxxxxxxxxxxxxxx
Shared Files: http://ontolog.cim3.net/file/
Community Wiki: http://ontolog.cim3.net/wiki/ 
To join: http://ontolog.cim3.net/cgi-bin/wiki.pl?WikiHomePage#nid1J
To Post: mailto:ontolog-forum@xxxxxxxxxxxxxxxx    (012)

<Prev in Thread] Current Thread [Next in Thread>