- From: Peter Frederick Patel-Schneider <pfps@research.bell-labs.com>
- Date: Thu, 7 Apr 2011 09:28:34 -0400
- To: <dpw@talis.com>
- CC: <lee@thefigtrees.net>, <alexhall@revelytix.com>, <public-rdf-wg@w3.org>
From: David Wood <dpw@talis.com> Subject: Re: [Graphs] g-snap vs. g-box and graph equality Date: Thu, 7 Apr 2011 07:56:53 -0500 > On Apr 6, 2011, at 23:37, Lee Feigenbaum <lee@thefigtrees.net> wrote: > >> On 4/6/2011 11:30 PM, Alex Hall wrote: >>> Just trying to get a handle on people's expectations around named graphs >>> as g-snaps vs. g-boxes as it relates to graph equality (and inequality). >>> >>> Given the two notional TriG/Qurtle fragments which we would like to combine: >>> >>> file-1.trig: >>> :G1 { :a :b :c } . >>> :G2 { :d :e :f } . >>> >>> file-2.trig: >>> :G1 { :a :b :d } . >>> :G3 { :d :e :f } . >>> >>> My impression so far is that some people want to treat named graphs as >>> g-snaps, and some as g-boxes. Suppose for a second that we treat them >>> as naming g-snaps. Without expressing an opinion one way or another, I ask: >>> >>> 1. Is the fact that G1 is mapped to two different g-snaps an inconsistency? >>> >>> 2. From the fact that G2 and G3 are mapped to the same g-snap, can we >>> conclude that G2 and G3 are in fact the same resource? >> >> I'm guessing that because of the OWA that the answer to both is "no", >> though I'm not really sure? > > I certainly hope that the answer to both is 'no'. > > Regards, > Dave Absent some semantics I don't see that the present tense can be used here. Absent some desiderata I don't see that this can even be weakened to the future subjunctive. Of course, it is always possible to hope that for a particular answer to be true in the future. The thorny issues that have to be worked out include things like whether RDF can exactly specify the contents of a named graph, and, if so, how. If the above indeed exactly specifies the contents of a named graph, then it better be the case that the two documents above are not consistent with each other, in a fashion similar to the two triples <ex:a> <ex:p> "<notLegalXML"^^rdf:XMLLiteral . and <ex:p> rdfs:range rdf:XMLLiteral . not being consistent with each other in RDFS. peter
Received on Thursday, 7 April 2011 13:29:25 UTC