W3C home > Mailing lists > Public > www-rdf-interest@w3.org > November 2003

Re: RDF query and Rules - my two cents

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Thu, 20 Nov 2003 11:30:55 +0200
Cc: Danny Ayers <danny666@virgilio.it>, www-rdf-interest@w3.org
To: mbatsis@netsmart.gr
Message-Id: <3DFD1564-1B3C-11D8-8364-000A95EAFCEA@nokia.com>


On Thursday, Nov 20, 2003, at 10:40 Europe/Helsinki, ext Emmanuil 
Batsis (Manos) wrote:

>
>
> Patrick Stickler (NMP-MSW/Tampere) wrote:
>
>> IMO, for the SW to reach critical mass, we have to (1) provide a 
>> simple,
>> effortless way to get descriptions of resources having only a URI, and
>> (2) get away from GETing explicit RDF/XML instances (files) rather
>> than querying knowledge bases.
>
> Heh. That sums it up pretty good :-)
>
>
>> Much better, IMO, to simply be able to ask
>> MGET http://dannyayers.com/ HTTP/1.1
>> MGET http://dannyayers.com/misc/foaf/ HTTP/1.1
>
> Hey, this would be really cool! It can even be used to give some 
> purpose to all those missused URLs.
>
> But I can only use Dunny's way on webserver Foo right now... It's 
> probably the best way to make it work with MGET later anyway.

I'm planning on releasing as open source two different URIQA
implementations, as well as a URIQA agent API, to make life
easier for folks wanting to make their web servers "URIQA
enlightened". Watch the space at http://sw.nokia.com/tools
just after the New Year.

Yet, since implementing support for MGET which redirects to
a locally deployed web service is a pretty tiny bit of
functionality to deploy, adding support to Apache, Tomcat,
etc. should allow pretty quick global deployment.

Time permitting, I hope to write a few such modules/plugins
(unless someone else beats me to it ;-)

> There some details to work out around MGET though. For example, 
> performing a GET on the two following URLs will probably give you the 
> same document:
>
> http://foo.bla/something
> http://foo.bla/something?param=value
>
> But this should not be the case with an MGET, as the two URLs are not 
> the same resource (or at least they don't have to) per RDF terms.
>

And how is that a problem?

If the two distinct URIs denote different resources, then MGET with
either will result in distinct descriptions. If the two URIs are
synonymous, then one may result in a full description, and the other
may be a description with a single owl:sameAs assertion indicating
its equivalence with the other.

This is one of the great features of MGET over GET, you avoid all
the ambiguity introduced by the URI resolution rewriting rules, so
that http://example.com can denote a web:Server, http://example.com/
can denote a web:Site, and http://example.com/index.html can denote
a web:Document and MGET will provide distinct and correct descriptions
of each distinct resource even though GET might return the very same
representation for all three.

Cheers,

Patrick


>
>
> -- 
> Manos Batsis
>
>     _  __    __                    __
>    / |/ /__ / /____ __ _ ___ _____/ /_
>   /    / -_) __(_-</  ' Y _ `/ __/ __/
>  /_/|_/\__/\__/___/_/_/_|_,_/_/  \__/
>
> () ASCII ribbon campaign - against HTML email
> /\                       - against Microsoft attachments
>
> http://www.netsmart.gr
> mbatsis at netsmart dot gr
> (+30) 210 33 02 608
> (+30) 210 33 02 658
> http://forte.netsmart.gr/foaf/manos_foaf.rdf
>
>
>
Received on Thursday, 20 November 2003 04:33:15 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:52:03 GMT