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Re: combination of RDF* and graph-level metadata (named graphs)

From: Dan Brickley <danbri@google.com>
Date: Fri, 30 Aug 2019 07:42:22 -0700
Message-ID: <CAK-qy=4w_90QcbEDPJO=+-DNfg1vEMJ0qT31Seg-+J8ixUy8eQ@mail.gmail.com>
To: Olaf Hartig <olaf.hartig@liu.se>
Cc: "public-rdf-star@w3.org" <public-rdf-star@w3.org>, David Booth <david@dbooth.org>
On Fri, 30 Aug 2019 at 03:36, Olaf Hartig <olaf.hartig@liu.se> wrote:

> Dan,
>
> I'm not sure I understand. What do you mean by "graph edges"?
>

I meant just triples / occurrences of properties

>
> Is your idea to use an RDF* triple to capture something like, e.g., "the
> graph denoted by IRI ex:mygraph contains the edge/triple (ex:Bob,
> foaf:knows, ex:Alice)." ?
>

Yes, or for that matter, expressing the same thing in property graphs


>
> Olaf
>
> -----Original Message-----
> From: Dan Brickley <danbri@google.com>
> To: Olaf Hartig <olaf.hartig@liu.se>
> Cc: "public-rdf-star@w3.org" <public-rdf-star@w3.org>, David Booth <
> david@dbooth.org>
> Sent: Fri, 30 Aug 2019 12:05
> Subject: Re: combination of RDF* and graph-level metadata (named graphs)
>
> Quick thought: we could also potentially use rdf* annotations to attach
> multiple graph edges to a named graph. That feels slightly less heavyweight
> than classical named graphs, although maybe the difference is trivial?
>
> Dan
>
> On Fri, 30 Aug 2019, 08:52 Olaf Hartig, <olaf.hartig@liu.se> wrote:
>
> > David,
> >
> > On torsdag 29 augusti 2019 kl. 14:14:39 CEST David Booth wrote:
> > > [...]
> > > My main concerns:
> > >
> > >   - It must be easy to make statements about an entire graph -- a set
> of
> > > triples -- rather than one triple at a time.  At present RDF* does not
> > > allow this, but my understanding is that it could be extended to do so.
> > > IMO this is critically important.
> >
> > I don't see why this would be necessary; I mean, I don't think we need
> > another
> > such approach. The approaches that you mention below (named graphs, as a
> > data
> > model feature, and the N3 syntax to talk about graphs) already give us
> the
> > means to make statements about an entire graph. Therefore, in contrast to
> > these approaches, RDF* focuses on making statements about individual
> > triples
> > (similar to standard RDF reification and edge properties in Property
> > Graphs).
> >
> > Making statements about entire graphs and making statements about
> > individual
> > triples are orthogonal issues. Of course, there are use cases in which we
> > want
> > to be able to do both within the same dataset. To this end, the concept
> of
> > a
> > named graph may simply be extended to be a pair consisting of an IRI (the
> > graph name) and an RDF* graph (rather than an RDF graph). Then, it is
> > possible
> > to use the IRI to make statements about the graph as a whole, and within
> > the
> > graph you may have (nested) RDF* triples to make statements about some
> > particular triple.
> >
> > >   - It should be harmonized with other existing mechanisms, such as
> > > named graphs and N3's ability to talk about graphs.
> >
> > Does the approach outlined above (named RDF* graphs) address this
> concern?
> >
> > Olaf
> >
> >
> > > Thanks!
> > > David Booth
> >
> >
>
Received on Friday, 30 August 2019 14:43:03 UTC

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