On 5 Mar 2011, at 15:23, Michael Hausenblas wrote: > >> I'm no SPARQL or voiD guru, but I think you need a bit more wrapping in the >> scovo stuff, so more like: > ROTFL, reading that Hugh claims to be *not* a VoID guru ;) Tee hee. Very kind, but > Note that SCOVO modelling of stats in VoID has been deprecated and simplified > [1].
sort of proves my assertion :-) And perhaps this little interchange proves the assertion in [1] "Statistics would be verbose, and querying them with SPARQL was difficult." I was looking at our voiD docs. Seems we have not updated them, and they still do scovo. Better make sure the boys get to work :-) > >> Fancy the challenge, it is the weekend?! :-) > > Indeed! Cheers > > Cheers, > Michael > [1] http://www.w3.org/TR/void/#statistics > -- > Dr. Michael Hausenblas, Research Fellow > LiDRC - Linked Data Research Centre > DERI - Digital Enterprise Research Institute > NUIG - National University of Ireland, Galway > Ireland, Europe > Tel. +353 91 495730 > http://linkeddata.deri.ie/ > http://sw-app.org/about.html > > On 5 Mar 2011, at 15:14, Hugh Glaser wrote: > >> Hi, >> On 5 Mar 2011, at 14:22, Andrea Splendiani wrote: >> >>> Hi, >>> >>> I think it depends on the store, I've tried some (from the endpoint list) >>> and some returns a answer pretty quickly. Some doesn't and some doesn't >>> support count. >>> However, one could have this information only for the stores that answers >>> the count query, no need to try all time. >> I am happy for a store implementor or owner to disagree, but I find it very >> unlikely that the owner of a store with a decent chunk of data (> 1M >> triples, say) would be happy for someone to keep issuing such a query, even >> if they did decide to give enough resources to execute it. >> I would quickly blacklist such a site. >>> >>> VoID: >>> is this a good query: >>> select * where {?s <http://rdfs.org/ns/void#numberOfTriples> ?o } >> >> I'm no SPARQL or voiD guru, but I think you need a bit more wrapping in the >> scovo stuff, so more like: >> >> SELECT DISTINCT ?endpoint ?uri ?triples ?uris WHERE >> { ?ds a void:Dataset . >> ?ds void:sparqlEndpoint ?uri . >> ?ds rdfs:label ?endpoint . >> ?ds void:statItem [ scovo:dimension void:numberOfTriples ; >> rdf:value ?triples ] . >> } >> >> Try it at >> http://kwijibo.talis.com/voiD/ >> or >> http://void.rkbexplorer.com/ >> >> I guess Pierre-Yves might like to enhance his page by querying a voiD store >> to also give basic stats. >> Or someone might like to do a store reporter that uses (a) voiD endpoint(s) >> plus Pierre-Yves's data (he has a SPARQL endpoint), to do so. >> And maybe the CKAN endpoint would have extra useful data as well. >> A real Semantic Web application that queried more than one SPARQL endpoint - >> now that would be a novelty! >> Fancy the challenge, it is the weekend?! :-) >> >> ciao >> Hugh >> >>> >>> it doesn't seem viable if so. >>> >>> ciao, >>> Andrea >>> >>> >>> Il giorno 05/mar/2011, alle ore 13.49, Hugh Glaser ha scritto: >>> >>>> NIce idea, but,... :-) >>>> >>>> SELECT (count(*) as ?c) WHERE {?s ?p ?o} >>>> >>>> is a pretty anti-social thing to do to a store. >>>> At best, a store of any size will spend a while thinking, and then quite >>>> rightly decide they have burnt enough resources, and return some sort of >>>> error. >>>> >>>> For a properly maintained site, of course, the VoiD description will give >>>> lots of similar information. >>>> Best >>>> Hugh >>>> >>>> On 5 Mar 2011, at 13:06, Andrea Splendiani wrote: >>>> >>>>> Hi, very nice! >>>>> I have a small suggestion: >>>>> >>>>> why don't you ask "count(*) where {?s ?p ?o}" to the endpoint ? >>>>> Or ask for the number of graphs ? >>>>> Both information, number of triples and number of graphs, if logged and >>>>> compared over time, can give a practical view of the liveliness of the >>>>> content of the endpoint. >>>>> >>>>> best, >>>>> Andrea Splendiani >>>>> >>>>> >>>>> Il giorno 28/feb/2011, alle ore 18.55, Pierre-Yves Vandenbussche ha >>>>> scritto: >>>>> >>>>>> Hello all, >>>>>> >>>>>> you have already encountered problems of SPARQL endpoint accessibility ? >>>>>> you feel frustrated they are never available when you need them? >>>>>> you develop an application using these services but wonder if it is >>>>>> reliable? >>>>>> >>>>>> Here is a tool [1] that allows you to know public SPARQL endpoints >>>>>> availability and monitor them in the last hours/days. >>>>>> Stay informed of a particular (or all) endpoint status changes through >>>>>> RSS feeds. >>>>>> All availability information generated by this tool is accessible >>>>>> through a SPARQL endpoint. >>>>>> >>>>>> This tool fetches public SPARQL endpoints from CKAN open data. From >>>>>> this list, it runs tests every hour for availability. >>>>>> >>>>>> [1] http://labs.mondeca.com/sparqlEndpointsStatus/index.html >>>>>> [2] http://ckan.net/ >>>>>> >>>>>> Pierre-Yves Vandenbussche. >>>>> >>>>> Andrea Splendiani >>>>> Senior Bioinformatics Scientist >>>>> Centre for Mathematical and Computational Biology >>>>> +44(0)1582 763133 ext 2004 >>>>> andrea.splendi...@bbsrc.ac.uk >>>>> >>>>> >>>>> >>>> >>>> -- >>>> Hugh Glaser, >>>> Intelligence, Agents, Multimedia >>>> School of Electronics and Computer Science, >>>> University of Southampton, >>>> Southampton SO17 1BJ >>>> Work: +44 23 8059 3670, Fax: +44 23 8059 3045 >>>> Mobile: +44 78 9422 3822, Home: +44 23 8061 5652 >>>> http://www.ecs.soton.ac.uk/~hg/ >>>> >>>> >>> >>> Andrea Splendiani >>> Senior Bioinformatics Scientist >>> Centre for Mathematical and Computational Biology >>> +44(0)1582 763133 ext 2004 >>> andrea.splendi...@bbsrc.ac.uk >>> >>> >>> >> >> -- >> Hugh Glaser, >> Intelligence, Agents, Multimedia >> School of Electronics and Computer Science, >> University of Southampton, >> Southampton SO17 1BJ >> Work: +44 23 8059 3670, Fax: +44 23 8059 3045 >> Mobile: +44 78 9422 3822, Home: +44 23 8061 5652 >> http://www.ecs.soton.ac.uk/~hg/ >> >> >> > -- Hugh Glaser, Intelligence, Agents, Multimedia School of Electronics and Computer Science, University of Southampton, Southampton SO17 1BJ Work: +44 23 8059 3670, Fax: +44 23 8059 3045 Mobile: +44 78 9422 3822, Home: +44 23 8061 5652 http://www.ecs.soton.ac.uk/~hg/
