- From: Kingsley Idehen <kidehen@openlinksw.com>
- Date: Tue, 05 Apr 2011 16:17:39 -0400
- To: William Waites <ww@styx.org>
- CC: "public-lod@w3.org" <public-lod@w3.org>, Virtuoso Users <virtuoso-users@lists.sourceforge.net>, "semantic-web@w3.org" <semantic-web@w3.org>, lotico-list@googlegroups.com
On 4/5/11 3:42 PM, William Waites wrote: > So I don't have answers to your questions, but do have some > observations about the results, particularly the counts of > distinct predicates. > > The top one is rdf:type which makes sense. Below that we > have ones used in reification. Who knew there was actually > that much reified data out there? I wonder where this comes > from and what about the consensus that this is not a good > idea and should be deprecated? > > SELECT DISTINCT ?graph, COUNT(?s) AS ?count WHERE { > GRAPH ?graph { ?s > ?p<http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement> } > } ORDER BY DESC(?count) LIMIT 50 > > This query times out, but it would be interesting to know > the answer, who is the source of all of these reifications? Yes, that will timeout via the public SPARQL endpoint. We'll run it internally to get the numbers. > Next is rdfs:label, ok, fine. After that, a sizeable chunk > of data has to do with rows and columns in CSV tables that > comes from data.gov. No, that's RDF from RPI's (Jim Hendler's team) conversion of Data.Gov datasets. That accounts for about 6.4 Billion triples re. total contribution. > How is a mechanical transliteration > from CSV to RDF without any modelling useful? That's a question for the team at RPI :-) > It just makes > the data a couple of orders of magnitude bigger and a few > more orders of magnitude more cumbersome to deal with. Yes and No. As will all of these matter utility lies in the eyes and fingers of the data beholder. > I > mean, being able to refer to a specific spreadsheet cell is > useful but how does actually materialising all of them do > anything but take up disk space and slow down queries? See comments above :-) > Cheers, > -w -- Regards, Kingsley Idehen President& CEO OpenLink Software Web: http://www.openlinksw.com Weblog: http://www.openlinksw.com/blog/~kidehen Twitter/Identi.ca: kidehen -- Regards, Kingsley Idehen President& CEO OpenLink Software Web: http://www.openlinksw.com Weblog: http://www.openlinksw.com/blog/~kidehen Twitter/Identi.ca: kidehen
Received on Tuesday, 5 April 2011 20:18:02 UTC