- From: Damian Steer <damian.steer@hp.com>
- Date: Thu, 29 Jul 2004 15:40:08 +0100
- To: Steve Harris <S.W.Harris@ecs.soton.ac.uk>
- Cc: www-rdf-interest@w3.org
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 29 Jul 2004, at 13:46, Steve Harris wrote: > > On Thu, Jul 29, 2004 at 12:29:26 +0100, Damian Steer wrote: >> I suspect (though Ryan will no doubt correct me) that what SIMILE >> needs >> is something like Joseki and BRQL's DESCRIBE [1], i.e. grab a bunch >> (vague enough? :-) of information about this resource (possibly >> plural). I certainly could have done with something like that for >> brownsauce. Something like bNode closure may be enough, although it >> goes horribly wrong for FOAF data (I used something similar but which >> doesn't explode on FOAF). > > Could you say something about the algorithm? I'm looking at > implementing > DESCRIBE at the moment, but I'm stuck on the FOAF issue too :) > > - Steve Anything to help :-) I've described it in [1] (pre-OWL) but it's pretty simple: 1. Start from X. 2. Keep going out until a) you hit a labelled node or b) you hit a bNode with an owl:ifp hanging off it (or daml:unambiguousProperty as was). (literals take care of themselves, of course) I also added the ability to say 'also keep going over nodes of this class', which can help for rdf:Seq and co. The motivation for browsing was that this gives you a graph where the 'leaves' are identifiable, so you can keep going. I use the scare quotes since identifiable bNodes aren't quite leaves, eg <foaf:Person> (starting point) .... <foaf:knows> <foaf:Person> (the 'leaf') <foaf:mbox rdf:resource="pldms@mac.com"/> (the actual leaves) <foaf:name>Damian Steer</foaf:name> <foaf:knows> ....... (we don't get here) </foaf:knows> </foaf:Person> </foaf:knows> .... </foaf:Person> (foaf:mbox is an ifp, btw) So if "Damian Steer" knows anyone else you don't get them (well, unless the starting person does), and the browser can provide a link labelled "Damian Steer" which is retrievable (get the thing with foaf:mbox pldms@mac.com). The downside is you'll probably need the schema. The upside is a single request doesn't grab everyone in the store :-) Damian [1] http://www.xml.com/pub/a/2003/02/05/brownsauce.html -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.4 (Darwin) iD8DBQFBCQxPAyLCB+mTtykRAuHiAJ9l0rnMmbsqMdPmMNAT6jwqqaEbzgCgnVj8 /0f6r6D+Fa03uMMdggVcmdw= =ARov -----END PGP SIGNATURE-----
Received on Thursday, 29 July 2004 10:41:21 UTC