Hi Mats,
What is the EC2 AMI instance type you are using and has the server been
configured to make maximum use of the resources (memory etc) as detailed in the
Virtuoso RDF Performance Tuning guide at:
http://virtuoso.openlinksw.com/dataspace/dav/wiki/Main/VirtRDFPerformanceTuning
This document also details now to check what indexes are in place, but the
defaults the restored MusicBrainz AMI is started with should suffice.
Should you still continue encountering performance problems, please provide the
explain output for the query(s) being run which will provide details of the
query execution plan as detailed at:
http://docs.openlinksw.com/virtuoso/fn_explain.html
Note the query will need to be prepended with the keyword "sparql" before
running the explain function such that it is directed to the SPARQL engine ...
Best Regards
Hugh Williams
Professional Services
OpenLink Software
Web: http://www.openlinksw.com
Support: http://support.openlinksw.com
Forums: http://boards.openlinksw.com/support
Twitter: http://twitter.com/OpenLink
On 15 May 2010, at 17:44, [email protected] wrote:
> Thanks Bob, that got rid of the error message at least :)
>
> I'm running my own instance of the MusicBrainz EC2 AMI because the endpoint
> on dbtune doesn't run on Virtuoso and I want to use bif:contains to use
> full-text search.
>
> I still haven't been able to get any data out though, when I try some queries
> they seem to go on forever. Do I need to set up some indexes?
>
> On Sat, May 15, 2010 at 5:33 PM, Bob Ferris <[email protected]> wrote:
> Hi Mats,
>
> I do not really know, which SPARQL endpoint you are querying, but for
> the case you tried http://dbtune.org/musicbrainz/sparql
>
> 1. you should change
> ?artist mo:creatorOf ?album
> to
> ?album foaf:maker ?artist
>
> 2. you should query with out the ";" at the end of your query.
>
> Good luck ;)
>
> Cheers,
>
> Bob
>
> Am 15.05.2010 16:59, schrieb [email protected]:
> > I'm trying to query a MusicBrainz EC2 AMI, but I'm getting an error. Can
> > anyone tell me what's wrong with this query?
> >
> > PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
> > PREFIX foaf: <http://xmlns.com/foaf/0.1/>
> > PREFIX mo: <http://purl.org/ontology/mo/>
> > PREFIX dc: <http://purl.org/dc/elements/1.1/>
> > SELECT ?artist_name ?album_title
> >
> > WHERE
> > {
> > ?artist rdf:type mo:SoloMusicArtist .
> > ?artist foaf:name ?artist_name .
> > ?artist mo:creatorOf ?album .
> >
> > ?album rdf:type mo:Record .
> > ?album dc:title ?album_title .
> >
> > FILTER bif:contains(?artist_name, "Paul") .
> > FILTER bif:contains(?album_title, "Press and Play") .
> > };
> >
> >
> >
> > ------------------------------------------------------------------------------
> >
> >
> >
> >
> > _______________________________________________
> > Virtuoso-users mailing list
> > [email protected]
> > https://lists.sourceforge.net/lists/listinfo/virtuoso-users
>
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