Re: What is Oracle's objection to the use of Turtle as R2RML syntax?

But it does now. I don't think that is an argument for not having a single
normative R2RML syntax

Juan Sequeda
+1-575-SEQ-UEDA
www.juansequeda.com


On Wed, Dec 14, 2011 at 9:05 AM, Souripriya Das
<SOURIPRIYA.DAS@oracle.com>wrote:

> I was talking about OWL (10-Feb-2004: http://www.w3.org/TR/owl-features/),
> which did not specify a syntax. -- Souri.
>
>
> ----- Original Message -----
> From: juanfederico@gmail.com
> To: richard@cyganiak.de
> Cc: souripriya.das@oracle.com, kidehen@openlinksw.com,
> public-rdb2rdf-wg@w3.org
> Sent: Wednesday, December 14, 2011 8:44:35 AM GMT -05:00 US/Canada Eastern
> Subject: Re: What is Oracle's objection to the use of Turtle as R2RML
> syntax?
>
>
>
> On Wed, Dec 14, 2011 at 5:23 AM, Richard Cyganiak <richard@cyganiak.de>wrote:
>
>> Souri,
>>
>> On 13 Dec 2011, at 23:40, Souripriya Das wrote:
>> > OWL too was called a language, "Web Ontology Language". But, it just
>> defined a vocabulary. It did not define any syntax.
>>
>> OWL defines three new syntaxes:
>>
>> http://www.w3.org/TR/owl2-syntax/
>> http://www.w3.org/TR/owl2-xml-serialization/
>> http://www.w3.org/TR/owl2-manchester-syntax/
>>
>> > One can use any RDF syntax (RDF/XML, N-Triple, ...) for OWL.
>>
>> [[
>> As noted above, any conformant OWL 2 tool MUST accept ontology documents
>> using the RDF/XML serialization … A conformant OWL 2 tool MAY also accept
>> ontology documents using other serializations, for example Turtle
>> ]]
>> http://www.w3.org/TR/owl2-conformance/#Tool_Conformance
>>
>> RDF/XML is the single normative OWL syntax. My desire is to have a single
>> normative R2RML syntax (but it should be Turtle rather than the outdated
>> and in many ways broken RDF/XML).
>>
>
> Ok. I'm now convinced. If RDF/XML is the single normative OWL syntax, then
> there should be a single normative R2RML syntax too... and RDF/XML is too
> complicated for this. So you got my vote for Turtle to be the "single
> normative R2RML syntax".
>
> However, other syntaxes *should* be supported by implementations. R2RML is
> basically a vocabulary. Written in Turtle, it looks like a language, but
> it's still a vocabulary. R2RML mappings are instantiations of this
> vocabulary. So technically, I can import the R2RML vocabulary into an
> ontology editor, and use the ontology editor to create the mappings. Does
> this really work right now? I don't know. Will people actually do this? I
> don't know. But it could. And all these tools support different syntaxes.
> So if I were to create an R2RML mapping using an existing ontology editor
> tool, export it as RDF/XML and send it to somebody else and they open it in
> an R2RML specific tool.. everything should work.
>
>
>> Best,
>> Richard
>>
>>
>>
>> >
>> > Thanks,
>> > - Souri.
>> >
>> > ----- Original Message -----
>> > From: kidehen@openlinksw.com
>> > To: public-rdb2rdf-wg@w3.org
>> > Sent: Tuesday, December 13, 2011 5:01:24 PM GMT -05:00 US/Canada Eastern
>> > Subject: Re: What is Oracle's objection to the use of Turtle as R2RML
>> syntax?
>> >
>> > On 12/13/11 4:51 PM, Richard Cyganiak wrote:
>> >> Hi Ashok,
>> >>
>> >> On 13 Dec 2011, at 21:11, ashok malhotra wrote:
>> >>> At the Linked Data Workshop last week IBM showed some slides that
>> used a RDF syntax called Trig.
>> >>> So, I looked up Trig
>> http://www.wiwiss.fu-berlin.de/suhl/bizer/TriG/Spec/ and found that you
>> were
>> >>> one of the authors.  So, Trig might be an alternate syntax for the
>> mapping language, no?
>> >>> Folks seemed to like it.  It is not a standard but may become one.
>> >> I like that example! R2RML already allows the use of TriG syntax, no
>> change required. TriG is a superset of Turtle. If you serialize an R2RML
>> mapping graph as TriG, you get a Turtle file.
>> >>
>> >>> It is also possible that
>> >>> other RDF syntaxes will appear and one of them will become dominant.
>>  If that happens,
>> >>> it would be good if users could  write R2RML in the new syntax.
>> >> It takes a while for a new syntax to be invented, be implemented, be
>> evangelized, become popular, and become a W3C Recommendation. In the case
>> of Turtle, 13 years. A future RDB2RDF WG can relax the Turtle requirement
>> for a future R2RML version if demand for other syntaxes materializes. This
>> is not something that needs to be considered for R2RML 1.0.
>> >>
>> >> [[
>> >> PROPOSAL: On ISSUE-57, let's just go with Turtle in order to get R2RML
>> 1.0 out of the door.
>> >
>> > +1
>> >
>> > Kingsley
>> >> ]]
>> >>
>> >> Best,
>> >> Richard
>> >>
>> >>
>> >>
>> >>> All the best, Ashok
>> >>>
>> >>> On 12/13/2011 12:07 PM, Richard Cyganiak wrote:
>> >>>> Souri, what you say here is all correct (well, some nitpicks
>> inline), but I still don't see the key question addressed: What makes
>> one-w3c-RDF-syntax-MUST better in your eyes? All you do below is show that
>> users and implementers will have to go through extra hoops if that proposal
>> is accepted, so you're actually sort of making a case against it…
>> >>>>
>> >>>> On 13 Dec 2011, at 16:34, Souripriya Das wrote:
>> >>>>> There are currently two proposed options:
>> >>>>> 1) Turtle-syntax-MUST
>> >>>>> 2) one-w3c-RDF-syntax-MUST
>> >>>>>
>> >>>>> The Turtle-syntax-MUST option does not support any syntax other
>> than Turtle for the R2RML mapping documents
>> >>>> (Right, R2RML *mapping documents* MUST be Turtle. But
>> implementations MAY still support any syntax other than Turtle.)
>> >>>>
>> >>>>> while the one-w3c-RDF-syntax-MUST option only requires at least one
>> of the (W3C Recommendation) RDF syntaxes be used for R2RML mapping documents
>> >>>>> (while, because of the Turtle-convertibility,  still allowing the
>> test cases, tutorials, books, etc. to be written in Turtle).
>> >>>> But one-w3c-RDF-syntax-MUST would equally allow tutorials and books
>> to be written in any other syntax, so we'll get books that teach R2RML
>> using RDF/XML syntax, tutorials that teach R2RML using RDFa syntax, et
>> cetera.
>> >>>>
>> >>>>> Again, here is the one-w3c-RDF-syntax-MUST proposal:
>> >>>>> [[
>> >>>>> An R2RML mapping document is any document that encodes an R2RML
>> mapping graph and
>> >>>>> is written in any RDF syntax that is a W3C Recommendation and that
>> can be converted to Turtle.
>> >>>>> ]]
>> >>>>> (By "Turtle" we mean the future Turtle W3C Recommendation)
>> >>>>>
>> >>>>> The following can be said about the effect of using the above
>> proposal:
>> >>>>>
>> >>>>> ------------------
>> >>>>> Consider an R2RML mapping document written in RDF/XML syntax:
>> >>>>> - Is it a conforming R2RML mapping document?
>> >>>>> YES. (for Turtle-syntax-MUST: NO)
>> >>>> …and this is literally the *only* difference. I don't understand who
>> benefits from this. Who is keen on calling an R2RML mapping graph
>> serialized in RDF/XML an R2RML mapping document, and why?
>> >>>>
>> >>>>> - Why?
>> >>>>> Because one can convert the document to generate an equivalent
>> document written in Turtle syntax.
>> >>>>>
>> >>>>> ---------------------
>> >>>>> Consider an R2RML mapping processor which ONLY accepts R2RML
>> mapping documents written in RDF/XML syntax:
>> >>>>> - Is it a conforming R2RML mapping processor?
>> >>>>> YES. (for Turtle-syntax-MUST: YES)
>> >>>>> - Why?
>> >>>>> Because it accepts all conforming R2RML mapping documents, written
>> in RDF/XML syntax.
>> >>>>>
>> >>>>> ---------------------
>> >>>>> Testing for conformance of an R2RML mapping processor that ONLY
>> accepts RDF/XML documents:
>> >>>> Yes, it's possible, but it's inconvenient for implementers. What
>> advantage balances this inconvenience?
>> >>>>
>> >>>>> For each test in "tests for conformance"
>> >>>>> 1) obtain the mapping documents (written in Turtle syntax)
>> >>>>> 2) Convert these Turtle-syntax mapping documents into RDF/XML
>> syntax (assuming this is possible)
>> >>>>> 3) Process the converted documents
>> >>>>> 4) Run the corresponding SPARQL queries from "tests for
>> conformance" and compare the results
>> >>>>> 5) If query results match, then this processor is indeed a
>> conforming R2RML mapping processor
>> >>>>>
>> >>>>> ---------------------
>> >>>>> Sharing of an R2RML mapping document between two non-overlapping
>> syntax accepting processors:
>> >>>> Yes, it's possible, but it's inconvenient for mapping authors and
>> admins. What advantage balances this inconvenience?
>> >>>>
>> >>>> I'm not saying that there is no advantage. I'm just saying that I
>> myself can't think of any, and that I can't recall anyone else mentioning
>> any!
>> >>>>
>> >>>> So, which stakeholder (WG members, implementers [incl. Oracle],
>> mapping authors) benefits from one-w3c-RDF-syntax-MUST, and how?
>> >>>>
>> >>>> Best,
>> >>>> Richard
>> >>>>
>> >>>>
>> >>>>> - MappingProcessor1 accepts ONLY RDF/XML and MappingProcessor2
>> accepts ONLY N-Triples
>> >>>>> - an R2RML mapping document (written in RDF/XML) and used at
>> MappingProcessor1 is to be shared with MappingProcessor2
>> >>>>> - convert the mapping document into an equivalent N-Triples
>> document (via Turtle, if direct conversion is not possible)
>> >>>>> - present the N-Triples R2RML mapping document to MappingProcessor2
>> >>>>>
>> >>>>> Thanks,
>> >>>>> - Souri.
>> >>>>>
>> >>>>> ----- Original Message -----
>> >>>>> From: richard@cyganiak.de
>> >>>>> To: souripriya.das@oracle.com
>> >>>>> Cc: public-rdb2rdf-wg@w3.org
>> >>>>> Sent: Wednesday, December 7, 2011 1:52:14 PM GMT -05:00 US/Canada
>> Eastern
>> >>>>> Subject: Re: What is Oracle's objection to the use of Turtle as
>> R2RML syntax?
>> >>>>>
>> >>>>> On 7 Dec 2011, at 18:07, Souripriya Das wrote:
>> >>>>>> Instead of the following definition of the mapping document:
>> >>>>>>
>> >>>>>> [[
>> >>>>>> An R2RML mapping document is any document written in the Turtle
>> [TURTLE] RDF syntax that encodes an R2RML mapping graph.
>> >>>>>> ]]
>> >>>>>>
>> >>>>>> we propose the following:
>> >>>>>>
>> >>>>>> [[
>> >>>>>> An R2RML mapping document is any document that encodes an R2RML
>> mapping graph and
>> >>>>>> is written in any RDF syntax that is a W3C Recommendation and can
>> be converted to Turtle [2].
>> >>>>>> ]]
>> >>>>> Why is this better?
>> >>>>>
>> >>>>> Richard
>> >>>>>
>> >>
>> >>
>> >
>> >
>> > --
>> >
>> > Regards,
>> >
>> > Kingsley Idehen
>> > Founder&  CEO
>> > OpenLink Software
>> > Company Web: http://www.openlinksw.com
>> > Personal Weblog: http://www.openlinksw.com/blog/~kidehen
>> > Twitter/Identi.ca handle: @kidehen
>> > Google+ Profile: https://plus.google.com/112399767740508618350/about
>> > LinkedIn Profile: http://www.linkedin.com/in/kidehen
>> >
>> >
>> >
>> >
>> >
>> >
>> >
>>
>>
>>
>