iSPARQL REST Mode Support

Virtuoso iSPARQL endpoint can be accessed via REST using http://host:port/isparql/view/ (e.g., OpenLink's Virtuoso Demo site iSPARQL endpoint, http://demo.openlinksw.com/isparql), with the following parameters:

  • format : specifies the request format (set by default to "application/rdf+xml").
  • defaultGraph : used as FROM, if not specified in query
  • query : the SPARQL query
  • named-graph-uri : used for named graphs, can be specified multiple times
  • maxrows : specifies limit on the results
  • sponge : specifies sponger cache behavior
  • endpoint : specifies sparql endpoint
  • file : .isparql, .ldr, and .rq resources

Example 1

Get 10 triples from demo Dataspace: 

SELECT * 
FROM <http://demo.openlinksw.com/dataspace>
WHERE {?s ?p ?o}
LIMIT 10
  1. Load this URL in your browser: 

    http://demo.openlinksw.com/isparql/view/?query=SELECT%20*%20%0AFROM%20%3Chttp%3A%2F%2Fdemo.openlinksw.com%2Fdataspace%3E%0AWHERE%20%7B%3Fs%20%3Fp%20%3Fo%7D%0ALIMIT%2010&endpoint=/sparql&maxrows=50&default-graph-uri=

  2. As a result, the triples found will be shown:



Example 2

Get 10 Weblog posts: 

prefix sioc: <http://rdfs.org/sioc/ns#> 
prefix sioct: <http://rdfs.org/sioc/types#>
prefix dct: <http://purl.org/dc/elements/1.1/>
prefix dcc: <http://purl.org/dc/terms/> 
SELECT DISTINCT ?forum_name, ?post, ?title ?cr ?url 
FROM <http://demo.openlinksw.com/dataspace>
WHERE    
  { 
    ?forum a sioct:Weblog .
    ?forum sioc:id ?forum_name .
    ?forum sioc:container_of ?post .
    OPTIONAL { ?post dct:title ?title } .
    OPTIONAL { ?post dcc:created ?cr } .
    OPTIONAL { ?post sioc:link ?url } .
  }
ORDER BY DESC (?cr)
LIMIT 10
  1. Load this URL in your browser: 

    http://demo.openlinksw.com/isparql/view/?query=prefix%20sioc%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Fns%23%3E%20%0Aprefix%20sioct%3A%20%3Chttp%3A%2F%2Frdfs.org%2Fsioc%2Ftypes%23%3E%0Aprefix%20dct%3A%20%3Chttp%3A%2F%2Fpurl.org%2Fdc%2Felements%2F1.1%2F%3E%0Aprefix%20dcc%3A%20%3Chttp%3A%2F%2Fpurl.org%2Fdc%2Fterms%2F%3E%20%0ASELECT%20DISTINCT%20%3Fforum_name%20%3Fpost%20%3Ftitle%20%3Fcr%20%3Furl%20%0AFROM%20%3Chttp%3A%2F%2Fdemo.openlinksw.com%2Fdataspace%3E%0AWHERE%20%20%20%20%0A%20%20%7B%20%0A%20%20%20%20%3Fforum%20a%20sioct%3AWeblog%20.%0A%20%20%20%20%3Fforum%20sioc%3Aid%20%3Fforum_name%20.%0A%20%20%20%20%3Fforum%20sioc%3Acontainer_of%20%3Fpost%20.%0A%20%20%20%20OPTIONAL%20%7B%20%3Fpost%20dct%3Atitle%20%3Ftitle%20%7D%20.%0A%20%20%20%20OPTIONAL%20%7B%20%3Fpost%20dcc%3Acreated%20%3Fcr%20%7D%20.%0A%20%20%20%20OPTIONAL%20%7B%20%3Fpost%20sioc%3Alink%20%3Furl%20%7D%20.%0A%20%20%7D%0AORDER%20BY%20DESC%20(%3Fcr)%0ALIMIT%2010&endpoint=/sparql&maxrows=50&default-graph-uri=

  2. As a result, the triples found will be shown:

See Also

Tagcloud

Category SPARQL Category RDF Category OpenSource Category OAT Category Documentation Category WebSite
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