Re: [External] : Re: An outline of RDFn -- RDF with (auto- and custom-) names

Hi Peter,

RDFn supports unasserted and asserted triples (and quads) as follows:

1) Each auto-named triple will be marked either as asserted or unasserted.

      a) Example 1: Asserted, auto-named triple: (every RDF1.1 triple maps to this type)
            ex:Cleveland ex:servedAs ex:POTUS .                              # asserted, auto-named triple

      b) Example 2: Unasserted, auto-named triple:
            << ex:Dukakis ex:servedAs ex:POTUS >> .                       # unasserted, auto-named triple

2) Custom-named triples for a given <s, p, o, g> are considered as unasserted UNLESS an asserted auto-named triple exists with the same <s, p, o, g>. Thus, this is a derived attribute for a custom-named triple, but a primary attribute (somewhat like "boolean isAsserted") for an auto-named triple.

      Example 3: The custom-named triples about Dukakis and Gore in the RDF data below are considered as unasserted, but the custom-named triple about Cleveland is considered as asserted.

            ex:Cleveland ex:servedAs ex:POTUS .                        # asserted, auto-named
            ex:Cleveland ex:servedAs ex:POTUS | ex:term2 .  # asserted, custom-named (b/c corr. auto-named triple exists and is asserted)

            << ex:Dukakis ex:servedAs ex:POTUS >> .      # unasserted, auto-named
            ex:Dukakis ex:servedAs ex:POTUS | ex:Duk.  # unasserted, custom-named (b/c corr. auto-named triple exists but is unasserted)

            ex:Gore ex:servedAs ex:POTUS | ex:Gore.        # unasserted (b/c no corr. auto-named triple exists)

3) When merging, multiple auto-named (source) triples having the same <s, p, o, g> get merged into a single auto-named triple that will be marked as unasserted UNLESS at least one of the (source) triples was marked as asserted.

Also, please note that, as mentioned in one of my earlier emails, SPARQL is extended to introduce << ... >> triple-patterns and isAuto(<nameVar>) boolean function to 1) allow matching unasserted triples as well, and 2) distinguish auto-named and custom-named triples when matching, respectively.

Thanks,
Souri.


________________________________
From: Peter F. Patel-Schneider <pfpschneider@gmail.com>
Sent: Monday, November 27, 2023 3:56 PM
To: public-rdf-star-wg@w3.org <public-rdf-star-wg@w3.org>
Subject: [External] : Re: An outline of RDFn -- RDF with (auto- and custom-) names

Is RDFn the same as RDF-star?   Well, in the sense that each can encode the
other, yes.  But this isn't a very useful sense of sameness.

More interesting is whether there is a natural correspondence between all of
RDFn and all of RDF-star.  But there isn't, at least so far as I can ascertain
from the information given to the working group.  RDF-star has unasserted
triples, which RDFn appears to lack.  RDFn uses graphs with multi-edges, which
RDF-star does not provide.

peter


On 11/26/23 22:08, Souripriya Das wrote:
> Since I did not hear any comments on RDFn during the first half of our last
> meeting that I was able to attend (except, maybe, Gregg might have said
> something right at the beginning but I had audio issues on my side), I thought
> it may be helpful to mention below a few high-level points about RDFn and how
> it is related to RDF-star concepts and syntax: ("statement" here simply means
> "a triple or quad"):
>
> 1) RDFn = RDF-star (which, I think, uses implicit naming in some sense, with
> << s p o >> as the name) + explicit naming (using IRIs as custom names).
>
> 2) RDFn (with appropriate syntactic shortcut) would appear exactly the same as
> RDF-star to a user who does not use multi-edges or statement-sets.
>
> 3) RDFn does not change anything regarding how users work with default graph
> and named graphs today.
>
> 4) RDFn requires use of explicit naming if user needs to store multi-edges.
> For modeling multi-edges, user does not need to introduce new triples or quads
> with special properties like :isOccurrenceOf or :hasOccurrence.
>
> 5) RDFn requires use of explicit naming for modeling statement-sets as well. A
> statement-set in RDFn can include (asserted or unasserted) triples from the
> default graph and the named graphs. The custom-name of a statement-set can be
> used for making statements about it.
>
> Thanks,
> Souri.