2 Replies Latest reply on Aug 3, 2016 8:01 PM by alwu-Oracle

    Fuseki Jena Adapter and spatial queries

    9fcf2b34-1d1f-4d59-82c3-aff6ac3e9f88
    9fcf2b34-1d1f-4d59-82c3-aff6ac3e9f88 Jul 8, 2016 12:56 PM

      I'm trying to setup a SPARQL endpoint using fuseki (the one bundled with the last Jena Adapter) and oracle 12c.

       

      If I try  a very simple spatial query on fuseki like:

       

      prefix ogc:<http://www.opengis.net/ont/geosparql#>

      prefix ogcf: <http://www.opengis.net/def/geosparql/function/>

      select ?s (ogcf:distance("POINT(11.2513 43.7770)"^^ogc:wktLiteral, "POINT(11.2512 43.7771)"^^ogc:wktLiteral,<http://xmlns.oracle.com/rdf/geo/uom/KM>) as ?dist) WHERE {

      ?s a ?t

      } limit 1

       

      that is simply calculating the distance among two points

      as result for the ?dist column nothing is produced.

       

      In the output of fuseki it is written

      WARN URI <http://www.opengis.net/def/geosparql/function/distance> has no registered function factory

       

      while if I try to do the same thing using SEM_MATCH

       

      SELECT s,dist FROM TABLE(SEM_MATCH(

      'select ?s (ogcf:distance("POINT(11.2513 43.7770)"^^ogc:wktLiteral, "POINT(11.2512 43.7771)"^^ogc:wktLiteral,<http://xmlns.oracle.com/rdf/geo/uom/KM>) as ?dist) where { ?s a ?t } limit 1',

      SEM_models('KM4C'),

      null,null,null));

       

      I get a result for dist!

       

      Any advice?

       

       

      Thanks,

      Pierfrancesco