- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Tue, 15 Mar 2011 14:47:26 +0000
- To: Ivan Herman <ivan@w3.org>
- Cc: Sören Auer <auer@informatik.uni-leipzig.de>, RDB2RDF WG <public-rdb2rdf-wg@w3.org>
On 15 Mar 2011, at 14:30, Ivan Herman wrote: > In practice, what I am a little bit concerned is that in a R2RML file there are two level of prefix mechanisms > > 1. Prefixes used for the R2RML language itself: R2RML is a set of RDF triples and if Turtle is used for their serialization then there are prefixes on that lefvel Note that this level can already be used in R2RML to abbreviate *some* URIs in the mapping file; in particular those that refer to classes and properties in the target vocabulary. This level is simply handled by the Turtle parser; any R2RML processor would already see those QNames expanded to full URIs. > 2. Prefixes used for the _content_ of those triples, ie, in the way the literals in those RDF triples are interpreted by an R2RML processor. > > I am just afraid that it will be easy to mix those two levels... I agree. That's why in D2RQ we avoided support for prefixes on the second level. The only mechanism for abbreviating URIs on that second level is expansion of relative into absolute URIs. That sufficient to cover the common use case of constructing resolvable URIs in the server's URI space. Best, Richard > But it may be worth brainstorming about it. > > I would not consider that as a showstopper for the next publication round, however. Let us leave that for the next round (at least imho) > > Ivan > > >> >> Sören >> > > > ---- > Ivan Herman, W3C Semantic Web Activity Lead > Home: http://www.w3.org/People/Ivan/ > mobile: +31-641044153 > PGP Key: http://www.ivan-herman.net/pgpkey.html > FOAF: http://www.ivan-herman.net/foaf.rdf > > > > >
Received on Tuesday, 15 March 2011 14:47:57 UTC