RDF-star profile "functional opaque” [Was: Re: The way forward]

Le 01/05/2024 à 17:27, Franconi Enrico a écrit :
> I have written down the formal definition of two profiles in the wiki:
> 
>   * RDF-star profile “transparent”
>     <https://github.com/w3c/rdf-star-wg/wiki/RDF-star-profile-%22transparent%22> (namely many-to-many transparent)
>   * RDF-star profile "functional opaque”
>     <https://github.com/w3c/rdf-star-wg/wiki/RDF-star-profile-%22functional-opaque%22> (namely many-to-one opaque)

Considering only the second item for the moment.

Assume we take 2 blank nodes b1 and b2, with b1 ≠ b2, and u1, u2 are 2 
IRIs. Then the triples t1 = (b1, u1, u2) and t2 = (b2, u1, u2) are 
different.
Then, since SRE is bijective, SRE(t1) ≠ SRE(t2).

Now, if we write things down in Turtle, how do we know if blank nodes 
appearing in different files, databases, or in-memory representation of 
RDF graphs correspond to the same, or different b-nodes.

For instance, if I have a Turtle file that just contains this triple:

<s> rdf:edge <<([] <p> <o>)>> .

And another Turtle file that contains exactly the same string, can we 
say that the graph of the first file entails the graph of the second?

This is a problem I already identified in Jan. 2023 when I proposed a 
semantics that is almost exactly the same as your RDF-star profile 
"functional opaque":

https://lists.w3.org/Archives/Public/public-rdf-star-wg/2023Jan/0100.html

As I said in this email: "One possible semantic extension of this could 
impose that isomorphic triples denote the same thing."

--AZ


> 
> They rely on two distinct properties - rdf:reifies and rdf:edge - and on 
> two distinct syntactic categories - tripleTerm and opaqueTripleTerm.
> For this reason, they could be just merged into a unique profile, which 
> actually could be RDF-star itself.
> 
> Let me know comments,
> cheers
> —e.
> 
>> On 25 Apr 2024, at 02:37, Lassila, Ora <ora@amazon.com> wrote:
>>
>> [My apologies that this comes at the last moment before tomorrow’s 
>> meeting.]
>> We have had long discussions within the Neptune team about the ongoing 
>> debate in the WG. We want to find an amicable, consensus-based way 
>> forward. Obviously the support within the WG for the multi-triple 
>> reifier proposal is strong, and we understand that many WG members may 
>> not be willing to live with the single-triple reifier approach. That 
>> said, we also believe that we (Neptune and our OneGraph project) need 
>> to be true to our vision of the future of “graph interoperability”.
>> Thus, we would like to bring back the idea of profiles: one for the 
>> multi-triple reifier support, another for the single-triple option. 
>> This would allow implementors some leeway, and would ultimately let 
>> the graph marketplace choose. People already make choices about what 
>> technologies they use, sometimes based on the level of support 
>> different technology vendors offer. Bottom line: we do not want to 
>> block progress in the WG, and this would let us move towards finishing 
>> the specifications. I think it is better that we get the largest 
>> possible number of implementors building RDF 1.2 -compliant products, 
>> rather than some companies “opting out”.
>> Ora
>> -- 
>> Dr. Ora Lassila
>> Principal Technologist, Amazon Neptune
> 

-- 
Antoine Zimmermann
École des Mines de Saint-Étienne
158 cours Fauriel
CS 62362
42023 Saint-Étienne Cedex 2
France
Tél:+33(0)4 77 49 97 02
https://www.emse.fr/~zimmermann/

Received on Thursday, 2 May 2024 12:38:54 UTC