- From: Steve Harris <steve.harris@garlik.com>
- Date: Thu, 3 Mar 2011 21:53:35 +0000
- To: Andy Seaborne <andy.seaborne@epimorphics.com>
- Cc: Richard Cyganiak <richard@cyganiak.de>, Sandro Hawke <sandro@w3.org>, nathan@webr3.org, RDF-WG <public-rdf-wg@w3.org>
On 2011-03-03, at 11:18, Andy Seaborne wrote: > On 03/03/11 07:51, Steve Harris wrote: ... >> Consequently there are several cases where the user would like to >> have different behaviours depending on whether the file you're >> parsing has 3 or 4 columns, so lets make it easy to find out without >> pre-parsing the whole file. > > Does > > N-quads serializes a dataset (default graph and named graphs) > N-Triples serializes a graph > > work for you? Yes. > It means that in N-Quads, the absence of the 4th column means default graph. I know 4Store does not have an independent default graph but some other systems do. N-Quads should capture the generality of an RDF dataset or graph store. FWIW, 4store does have a default graph (now), but internally it has a URI. By default it's just treated like another named graph. I have a slight reservation about having N-Quads lines with only 3 columns writing to the default graph, it means that "mv foo.nt foo.nq" gives a syntactically legal file, but changes the meaning of the file quite dramatically. Something more like the following would be my preference: <http://example.com/a> <http://example.com/a> <http://example.com/a> DEFAULT . It also ties in to SPARQL 1.1's DROP DEFAULT etc. - Steve -- Steve Harris, CTO, Garlik Limited 1-3 Halford Road, Richmond, TW10 6AW, UK +44 20 8439 8203 http://www.garlik.com/ Registered in England and Wales 535 7233 VAT # 849 0517 11 Registered office: Thames House, Portsmouth Road, Esher, Surrey, KT10 9AD
Received on Thursday, 3 March 2011 21:54:12 UTC