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1.5.74.How can I Determine the data usage across a Virtuoso instance? Home 1.5.76.How to split a urlencoded ";-" separated list of urls in a SPARQL query?

1.5.75.How to discover the capabilities of a SPARQL endpoint to enhancing SPARQL-FED usage from Virtuoso instances?

What?

How to discover the capabilities of a SPARQL endpoint en route to enhancing SPARQL-FED usage from Virtuoso instances.

Why?

There are features supported in Virtuoso SPARQL that aren't supported by other SPARQL engines. There are also a lot of Virtuoso instances behind bubbles in the LOD cloud. Net effect, a Virtuoso instance operator is faced with varied behavior when attempting to use SPARQL-FED functionality.

How?

Run this command to load metadata (or lack thereof) from an external SPARQL endpoint:

SPARQL LOAD SERVICE <{sparql-endpoint-iri> DATA
Example

  1. Run:

    Query result:
ANY
 Load service <http://lod.openlinksw.com/sparql> data -- done.
 Trying to query <http://lod.openlinksw.com/sparql> as SPARQL web service endpoint, POST mode...

  2. Check the retrieved data:

    SPARQL
SELECT *
  FROM virtrdf:
 WHERE
     {
       <http://lod.openlinksw.com/sparql> ?p ?o
     }
 LIMIT 10

Query result:
p                                                                o
ANY                                                              ANY
http://www.openlinksw.com/schemas/virtrdf#isEndpointOfService      http://lod.openlinksw.com/sparql-sd
http://www.openlinksw.com/schemas/virtrdf#dialect                000037ff
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1.5.74.How can I Determine the data usage across a Virtuoso instance? Home 1.5.76.How to split a urlencoded ";-" separated list of urls in a SPARQL query?