Re: Finding SPARQL endpoints

Hello Hugh,

On Tue, Oct 01, 2013 at 04:29:50PM +0000, Hugh Glaser wrote:
> Did you know about http://labs.mondeca.com/sparqlEndpointsStatus/ ?
> If so, can you give us some idea of the different sets or whatever please - I think they have 480 endpoints.
> Maybe you could helpfully collaborate with Pierre-Yves to get a more comprehensive list between you?

I see that http://labs.mondeca.com/endpoint/ends is not in my list and will
rerun my query with that additional endpoint. This should add those 480 
endpoints to the list - if not already there.

Unfortunately, my query does not work any more after an update of Fuseki.
I will have to check if the bug is in the new version or in the old version
and in my SPARQL query.

> I notice that quite a few of the (RKB) endpoints are listed as "no", when they are in fact up, and have been all the time.

Can you give an example ?

My measurement method is sending this via federation:

 select ?p where { { ?s ?p ?o } UNION { GRAPH ?g1 { ?s ?p ?o } } } limit 1

It will not work if the endpoint requires authentication or redirects to a new
endpoint URL. The named graph part of the query also seems to be unsupported
by some endpoints. For example, http://citeseer.rkbexplorer.com/sparql/ will
give me this error message: 

 SQL error in 'CREATE /* TMP */ TABLE uit (bm integer NOT NULL) 

Should I remove the named graph part ? How many endpoints are there in the 
wild containing useful information in named graphs ?

Regards,

Michael Brunnbauer

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