回复: Relationship and difference between N3 and RDF*

Dear William:
Thank you very much for your detailed explanation of N3, TRIG, and RDF*,  I now have a general idea of how they relate. But in practice, I still don't know which one to choose.
In most cases, can I use N-quads or named graph, Like this:
        ex:bob a ex:Person .
        ex:bob  ex:haschild  ex:meli  ex:ng1 .
        ex:ng1  ex:saidBy  ex:lucy .
Does this have the same effect as RDF* ?
In addition, about  “N3 adds an If-Then style of decision making in the form of logical implications and variables”, I would like to know the current progress in this respect, what kind of expression will be used?   Does it have anything to do with ruleML or DMN?

Best,
Joylix

发件人: William Van Woensel<mailto:william.vanwoensel@gmail.com>
发送时间: 2021年6月7日 21:23
收件人: Joy lix<mailto:joylix4112@outlook.com>; public-rdf-star@w3.org<mailto:public-rdf-star@w3.org>
抄送: Dörthe Arndt<mailto:doerthe.arndt@ugent.be>
主题: Re: Relationship and difference between N3 and RDF*


Hi Joy,

Thanks for looking into Notation3 (N3). Re the W3C specification - it builds on top of prior "complete" W3C submissions (e.g., see here<https://www.w3.org/TeamSubmission/n3/> and here<https://www.w3.org/DesignIssues/Notation3>) - hence the new incomplete spec<https://w3c.github.io/N3/spec/> may be giving a bit of a misleading view on the current state of N3: there are already mature systems that implement N3 (Eye and cwm). Our effort at https://w3c.github.io/N3/spec/ is meant to further standardize and flesh out N3, since the prior documents are a bit vague on certain aspects.

Re the difference with TriG: N3 allows quoted graphs (a.k.a. cited formulae<https://w3c.github.io/N3/spec/#cformulae>) to be utilized within triple statements, e.g., ":william :said { :william :wrote :moby_dick }", whereas TriG supports graph statements such as ":authorship_lies { :william :wrote :moby_dick }" that allow specifying named graphs. Both serve similar purposes - attaching context, provenance, and general metadata to statements - but have different semantics. Well, AFAIK named graphs do not really have an agreed-upon semantics - see here<https://www.w3.org/TR/2014/NOTE-rdf11-datasets-20140225/> for a list of possible interpretations of named graphs - while cited formulae have more of a fixed semantics as referentially-opaque RDF graphs (this corresponds to a particular interpretation<https://www.w3.org/TR/2014/NOTE-rdf11-datasets-20140225/#the-graph-name-denotes-the-named-graph-or-the-graph> of named graphs).

You may notice that this is where there is an overlap with RDF*, since it also means to allow attaching metadata to statements - in their case, by simplifying reification within RDF.

Hope that answers your question.



Regards,

William


On 2021-06-05 7:25 p.m., Joy lix wrote:
I'm a beginner in semantic technology, and I'm learning about RDF*.
I notice that another W3C specification is also being drafted : https://w3c.github.io/N3/spec/ . Also it mentioned: “N3 adds an If-Then style of decision making in the form of logical implications and variables”.
But I feel like it's not quite up to speed with RDF*, because there are a lot of sections that still say "bla...".
I don't know how it is related to or different from RDF*, there is also the W3C's TRIG, would some expert explain this briefly?   Thanks.

Regards,
Joylix