- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Thu, 6 May 2004 13:38:20 +0100
- To: Jeremy Carroll <jjc@hplb.hpl.hp.com>, Jeen Broekstra <jeen@aduna.biz>, www-rdf-interest@w3.org
- Cc: Arjohn Kampman <arjohn.kampman@aduna.biz>
-------- Original Message -------- > From: www-rdf-interest-request@w3.org <> > Date: 6 May 2004 13:24 > > > Steve Harris wrote: > > > > > On Thu, May 06, 2004 at 10:16:35 +0100, Phil Dawes wrote: > > > > > > > SELECT ?family , ?given > > > > WHERE (?vcard vcard:FN "John Smith") > > > > (?vcard vcard:N ?name) > > > > (?name vcard:Family ?family) > > > > (?name vcard:Given ?given) > > > > USING vcard FOR <http://www.w3.org/2001/vcard-rdf/3.0#> > > > > > > > > > > > > Unfortunately both Sesame(1.0) and RAP(0.71) require '<' and '>' > > > > around qnames for the query to parse. > > > > > > > > > FWIW 3store requires both <>'s and commas, the commas thing is a > > > bug and will be fixed. I'm be reluctant to remove or stop > > > requireing the <>'s as I think it makes the queries more readable. > > > > ObAOL: Ditto for Sesame. > > What about the potential confusion between <vcard:Family> qname and > <vcard:Family> new URI scheme? I can't find the definition of the vcard: URI scheme just at the moment. RDQL/Jena looks at <> things to see if there is such a prefix is defined. If it is, then it's a qname-like thing and prefix/localname concatentation is done; if not, its left as is. So don't define a prefix of http: :-) This is all for compatibility with RDF with incorrect URIs in it and also where databases have got scrambled by charset mismatches in the past. The use of <> on qnames allows quoting of characters ouside the grammar production for qnames and then forcing the query to be read not as UTF-8. Andy > > While I don't use RDQL much, I note that N3 has the same convention: <> > indicate URI, no-<> indicates qname. > > > > Jeremy
Received on Thursday, 6 May 2004 08:38:40 UTC