- From: Hugh Glaser <hg@ecs.soton.ac.uk>
- Date: Sat, 21 Sep 2013 23:29:50 +0000
- To: Jerven Bolleman <jerven.bolleman@isb-sib.ch>
- CC: William Waites <ww@styx.org>, "public-lod@w3.org community" <public-lod@w3.org>
Thanks Jerven, you may well be right! SELECT DISTINCT * WHERE { ?s foo:bar ?o } would do. And things like SELECT DISTINCT * WHERE { ?v1 foo:bar ?o . ?v1 ?p1 ?v2 . ?v2 ?p2 ?v3 } and then probably get back an identifier for each result, so that I can find out what are the values of the ?p* and ?v* I think essentially the sort of thing that dbpedia/virtuoso is giving me. (By the way, Kingsley, replying to this has caused me to notice that the rdfxml does not rapper very nicely - sorry to report! rapper: Error - URI file:///home/hg/sparql.rdf:8 - property element 'solution' has multiple object node elements, skipping.) Best Hugh On 21 Sep 2013, at 23:32, Jerven Bolleman <jerven.bolleman@isb-sib.ch> wrote: > Hi Hugh, > > I think you disregarded the CONSTRUCT queries a bit to quickly. This is what you use when you want to get back triples. > If you want back result columns you use SELECT. If you want describe to the concept of result columns in RDF then you are > on your own. > > Maybe if you explain what you want to represent then we can have a bit more of an informed discussion. > > Regards, > Jerven > On Sep 21, 2013, at 8:38 PM, Hugh Glaser <hg@ecs.soton.ac.uk> wrote: > >> Many thanks, William, and for confirming so quickly. >> (And especially thanks for not telling me that CONSTRUCT does what I want!) >> I had suddenly got excited that RDF might actually be useable to represent something I wanted to represent, just like we tell other people :-) >> So it is all non-standard, as I suspected. >> Ah well, I'll go back to trying to work with XML stuff, instead of using my usual RDF tools :-( >> Very best >> Hugh >> >> On 21 Sep 2013, at 19:14, William Waites <ww@styx.org> >> wrote: >> >>> Hi Hugh, >>> >>> You can get results in RDF if you use CONSTRUCT -- which is basically >>> a special case of SELECT that returns 3-tuples and uses set semantics >>> (does not allow duplicates), but I imagine that you are aware of this. >>> >>> Returning RDF for SELECT where the result set consists in n-tuples >>> where n != 3 is difficult because there is no direct way to represent >>> it. >>> >>> Also problematic is that there *is* a concept of order in SPARQL query >>> results while there is not with RDF. >>> >>> Also the use of bag semantics allowing duplicates which also does not >>> really work with RDF. >>> >>> These, again, could be kludged with reification, but that is not very >>> elegant. >>> >>> So most SELECT results are not directly representable in RDF. >>> >>> Cheers, >>> -w >>> >> >> > > ------------------------------------------------------------------- > Jerven Bolleman Jerven.Bolleman@isb-sib.ch > SIB Swiss Institute of Bioinformatics Tel: +41 (0)22 379 58 85 > CMU, rue Michel Servet 1 Fax: +41 (0)22 379 58 58 > 1211 Geneve 4, > Switzerland www.isb-sib.ch - www.uniprot.org > Follow us at https://twitter.com/#!/uniprot > ------------------------------------------------------------------- > >
Received on Saturday, 21 September 2013 23:30:26 UTC