W3C home > Mailing lists > Public > www-rdf-interest@w3.org > January 2002

Re: name that URI was: Re: RDFCore WG: Datatyping documents

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Tue, 29 Jan 2002 14:08:01 +0200
To: ext Jonathan Borden <jborden@mediaone.net>, RDF Interest <www-rdf-interest@w3.org>
CC: RDF Comments <www-rdf-comments@w3.org>
Message-ID: <B87C5D41.C928%patrick.stickler@nokia.com>
On 2002-01-29 3:46, "ext Jonathan Borden" <jborden@mediaone.net> wrote:

> 
> Patrick Sticker wrote:
> 
> ..
>> 
>> However, one final comment, I think that it is possible to work
>> with XML Schema datatype URIs with the present RDF/XML serialization
>> without recourse to qnames. We do, however, tend to use qnames
>> in examples for discussion as a convenience, but could also use
>> only URIs.
> 
> 
> perhaps an example makes my point: let's start with the following XML Schema
> which has the
> baseURI=http://example.com/XSD.xsd
> 
> <xsd:schema xmlns:xsd=http://www.w3.org/2001/XMLSchema
>               xsd:targetNamespace=http://example.org/foo-schema-ns
>               xmlns:ns=http://example.org/foo-schema-ns
>> 
>   <xsd:complexType name="bongo" id="foo">
>           ...
>   </xsd:complexType>
> </xsd:schema>

Well, just a nit, but we're talking about simple types. Complex
types are not intended to be supported by RDF -- but that doesn't
invalidate the important parts of your example.

> now the question:
> what is the URI of the complex type identified by the QName "ns:bongo" ?
> 
> Hint: according to http://www.w3.org/2001/XMLSchema it is NOT
> 
> http://example.org/foo-schema-nsbongo

I'm presuming it is http://example.org/foo-schema-ns#bongo, right?

So if I write

<rdf:Description rdf:about="#someProperty">
  <rdfs:range rdf:resource="http://example.org/foo-schema-ns#bongo"/>
</rdf:Description>

or

<rdf:Description rdf:about="#something">
   <someProperty>
       <rdf:Description>
          <rdf:type rdf:resource="http://example.org/foo-schema-ns#bongo"/>
          <rdf:value>Foo</rdf:value>
       </rdf:Description>
   </someProperty>
</rdf:Description>

where is the problem?

To take this further, if I write

<rdf:Description rdf:about="#something">
   <someProperty>
       <foo:bongo xmlns:foo="http://example.org/foo-schema-ns#"
rdf:value="Foo"/>
   </someProperty>
</rdf:Description>

and this is ever only processed by an RDF parser, again
where is the problem?

I agree that it's not ideal, and that the namespace
defined in the RDF space is not the same namespace
defined in the XML Schema space, but that is due
to a shortcoming of the XML Namespace spec, such that
there are mulitple possible (and valid) interpretations.

In the RDF context, direct concatenation is used, so
we need the final '#' in the *RDF* definition of
that namespace. In the XML Schema context, a different
method of URI construction is used, and the '#' is not
needed.

The bottom line is that, it works, we can use it, and
that's the best we are going to get just now.

Or shall we throw the baby out with the dirty bathwater?

Patrick


--
               
Patrick Stickler              Phone: +358 50 483 9453
Senior Research Scientist     Fax:   +358 7180 35409
Nokia Research Center         Email: patrick.stickler@nokia.com
Received on Tuesday, 29 January 2002 07:07:00 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:51:52 GMT