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Re: URI aliases for RDF terms?

From: Steve Harris <steve.harris@garlik.com>
Date: Wed, 16 Nov 2011 12:58:19 +0000
Cc: Eric Prud'hommeaux <eric@w3.org>, Ivan Herman <ivan@w3.org>, Ian Davis <ian.davis@talis.com>, W3C RDF WG <public-rdf-wg@w3.org>
Message-Id: <BB032BFB-D995-40E4-A67D-5D9BA6DC7542@garlik.com>
To: Richard Cyganiak <richard@cyganiak.de>
On 2011-11-13, at 16:44, Richard Cyganiak wrote:

> On 12 Nov 2011, at 23:06, Eric Prud'hommeaux wrote:
>> Following this scenario, we could say that <http://n.w3.org/rdf/type> and <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> are the same node
> 
> No, they will always be different nodes, but it could be made so that in RDF 2.0 / SPARQL 2.0, the query SELECT * WHERE { ?s a ?o } would match either of these nodes. This could be achieved in various ways, for example by baking the equivalence of these terms into the basic RDF 2.0 semantics.
> 
> If we *want* to have shorter IRIs for basic RDF/RDFS/OWL terms, then surely we can find some way to make it work, no? And surely, laying some initial non-normative groundwork *now* will help a lot to prepare for a normative introduction of these IRIs in a future round of RDF/SPARQL standardization a few years down the road.

Despite it raising my hackles somewhat initially, I'm kind of warming to this idea. Or at least regarding it as inevitable.

Re. what Eric said though, I believe that to make this be friendly to the way people use SPARQL now (e.g. being able to ask cardinality questions, and use it for financially important things like accounting) SPARQL stores would need to normalise to one URI form internally.

Then, we have several bad choices, including:

1) replace rdf: with newrdf: in data and queries - surprising anyone that's been using RDF for any length of time, and breaking their apps
2) replace newrdf: with rdf: in data and queries - surprising anyone that's new to RDF
3) try and guess from the query/request which prefix their using, and normalise to that on output

Those choices all suck for someone. Could be there's a magic solution where everyone is happy that I've not considered of course.

The only thing I can imagine is the normalisation being configurable per-store, with some common default for RDF 2.0 systems. I predict that being OK with users, bearable for implementers, but making the spec very ugly.

- Steve

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Received on Wednesday, 16 November 2011 12:59:04 GMT

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