- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Mon, 17 Jan 2005 12:04:53 +0000
- To: Benjamin Nowack <bnowack@appmosphere.com>
- CC: public-rdf-dawg-comments@w3.org
Benjamin Nowack wrote: > > hi again, > > an adjusted version of my comment from yesterday[1] as > just some extended food for thought. The idea is to > introduce a reification shortcut that could be used for > the SOURCE use cases and also for any other custom rdf > store extension: > > [[[ > ... > SELECT ?s ?p ?o > WHERE ( ?s rdf:type foaf:Person ) > ( ?s ex:ppd ?ppd ) > ( ?ppd rdf:type foaf:PersonalProfileDocument ) > ( ?ppd foaf:primaryTopic ?s ) > REIF (?s ex:ppd ?ppd) sparql:source <http://trustMe.com/ppdDump> > (?s ?p ?o) sparql:source ?ppd > (?s ?p ?o) ex:addedDate "2004-01-13" > ]]] In the new style I think that's just: SOURCE <http://trustMe.com/ppdDump> (?s ex:ppd ?ppd) that is, graph <http://trustMe.com/ppdDump> asserts (?s ex:ppd ?ppd) There would then be triples about <http://trustMe.com/ppdDump> saysing when it was added, what its trust status is etc etc. [incidently that query may be not what you want - ?s is likely to be a bNode in the unnamed graph] > > The reification constraint pattern > ([s] [p] [o]) [prop] [value] > would mean that there had to be an rdf:Statement with [s],[p],[o] > as rdf:subject,rdf:predicate,rdf:object, and that there's also > a matching ([statement] [prop] [value]) triple. That would be reification AND the original triple. That makes the triple asserted as true. > store developers > could freely decide how to implement this extended functionality > (explicit reification or with quads etc.) but the query syntax > could be generic. and using URIrefs for the [prop]s instead of > a single built-in SOURCE keyword for n-tuple stores would > keep SPARQL extensible. > > > regards and apologies for the (probably too) late comments, > benjamin Never too late. I'll take this as a suggestion for syntax support for reification and pass it onto the working group as such. Andy > > [1] > http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2005Jan/0002.html > > -- > Benjamin Nowack > > appmosphere web applications > Kruppstr. 100 > 45145 Essen, Germany > > http://www.appmosphere.com/ > >
Received on Monday, 17 January 2005 12:05:19 UTC