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Re: heading toward datatyping telecon

From: Brian McBride <bwm@hplb.hpl.hp.com>
Date: Thu, 01 Nov 2001 17:12:23 +0000
Message-ID: <3BE18277.7070702@hplb.hpl.hp.com>
To: Sergey Melnik <melnik@db.stanford.edu>
CC: RDFCore WG <w3c-rdfcore-wg@w3.org>, Pat Hayes <phayes@ai.uwf.edu>


Sergey Melnik wrote:

> Folks (esp. Pat),
> 
> I'd like to keep the fruitful momentum around datatyping.


+1

[...]

> However, I
> think the datatyping discussion needs some well-defined deliverables.
> One of them could be to specify how XML Datatypes (at least the
> primitive ones) should (or SHOULD) be used in RDF. 


As I see it the following deliverables are related to this discussion:

   o the core RDF specs, specifically the model theory, schema and the primer are
     all affected
   o from the charter:
          provide an account of the relationship between RDF and the
          XML family of technologies (particularly Schemas and
          Infoset/Query)

We got into this by way of trying to understand what literals are in RDF, 
looking first at xml:lang and then at rdf:parseType="Literal".  It doesn't seem 
reasonable to make a decision about those issues in isolation from datatyping 
question.

I think the expectation is that the second of these deliverables would be a W3C 
note, not a normative document.  Is that what you had in mind Sergey?

>I'd like to suggest
> that we vote on this deliverable next Friday.


As I recall, you accepted an action from the chair to write up, for circulation 
and review by the community, an approach to datatyping in RDF.  Checking

   http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Oct/0581.html

no action is recorded :(  We can formalise that this week.


> 
> <SUG2> was to focus on representing typing info in the triple
> structure. To my knowledge, there haven't been any public objections
> so far. Several schemes discussed on the list recently were in synch
> with SUG2. It seems that we are already going down the SUG2 path, so
> maybe voting is not even necessary - but it would be nice to do so for
> the record.


I have been concerned about the implementation costs of the triples approach, 
but I'd like to have some real implementation experience to back that up with. 
I do know that Jena's current implemenatation of reification, where it tries to 
not store the 4 triples separately, but just store the statement once, with an 
isReified flag, is unsatisfactory.  I'm nervous that we'll be creating  a 
similar problem here.

Jeremy's post of Andy Seaborne's comments is in a similar vein.

However, if I've groked what Pat is upto correctly, then I think I can see how 
to address these implementation concerns.  So going down the triples route is ok 
with me.  I do think we will need to get real implementation experience though.

Brian
Received on Thursday, 1 November 2001 12:19:55 EST

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