Re: Consolidating triple/edges -- named occurrence version

On Fri, 2024-01-05 at 13:55 +0000, Franconi Enrico wrote:
> > On 5 Jan 2024, at 14:46, Olaf Hartig <olaf.hartig@liu.se> wrote:
> > 
> > On Fri, 2024-01-05 at 10:58 +0000, Franconi Enrico wrote:
> > > On 5 Jan 2024, at 11:42, Niklas Lindström <lindstream@gmail.com>
> > > wrote:
> > > > Of course, it has implications for how to define these
> > > > occurrences
> > > > (truth-makers, right [1]?), which we need to come to terms with
> > > > together.
> > > > For example, I think this makes sense:
> > > > 
> > > >    << :wed-1 | :liz :spouse :richard >> .
> > > >    << :wed-1 | :richard :spouse :liz >> .
> > > >    :wed-1 a :Marriage ;
> > > >        :starts 1964 ;
> > > >        :ends 1974 .
> > > > 
> > > > Would you agree?
> > > 
> > > 
> > > Yes, it does.
> > 
> > Notice that this diverges quite a bit from the Property Graph
> > perspective. PG folks would understand the IRI :wed-1 to be an
> > identifier of an edge, and they would see two edges here (one from
> > :liz to :richard and another one from :richard to :liz). Then, they
> > would get confused because two different edges cannot have the same
> > identifier.
> 
> I agree. However, as I observed yesterday, the identity of PG edges
> should be encoded in RDF by the property names (emulating a singleton
> property), and not by reification.

Mmh. From a PG perspective, the predicate of a triple---assuming
triples with a non-literal object---is like the label of an edge. In
this sense, what you are proposing would appear to PG folks as
(mis)using the edge labels as means to identify/distinguish all the
edges.

> Reification then helps to add properties to the uniquely identified
> edges.
> This is of course possible with the current semantics.
> 
> > Notice also that a semantics such as this would probably not be
> > very
> > useful for provenance use cases. I would assume that, in such use
> > cases, it makes a difference whether the provenance annotation is
> > about
> > the triple (:liz, :source, :richard) or about the triple (:richard,
> > :source, :liz).
> 
> 
> I also agree here. Proper provenance use cases do need a more
> “syntactical” approach and therefore some form of opacity.
> However, the WG decided to go full steam to a fully transparent
> (i.e., semantic) approach.

When did this happen? In the WG meeting before Christmas (which I
didn't attend) or in any of the SemTF meetings?

Olaf


> That’s why yesterday I proposed that we could study extensions of
> this current approach to include optionally some form of opacity
> (whatever this may mean…).
> 
> cheers
> —e.
>

Received on Friday, 5 January 2024 14:38:25 UTC