sparql

pig build pkg pgsparql;		# build rpm/deb

pig repo add pgsql -u   # add both repo and update cache

pig install pgsparql;		# install via package name, for the active PG version
pig install sparql;		# install by extension name, for the current active PG version

pig install sparql -v 18;   # install for PG 18
pig install sparql -v 17;   # install for PG 17
pig install sparql -v 16;   # install for PG 16
pig install sparql -v 15;   # install for PG 15
pig install sparql -v 14;   # install for PG 14

CREATE EXTENSION sparql CASCADE; -- requires plperl, plperlu

SELECT * FROM sparql.get_properties('dbpedia', 'http://dbpedia.org/resource/Johann_Sebastian_Bach');

SELECT * FROM sparql.get_references('dbpedia', 'http://dbpedia.org/resource/Johann_Sebastian_Bach');

SELECT sparql.compile_query(endpoint, identifier, sparql_query [, grouping]);

SELECT sparql.compile_query('dbpedia', 'ludwig_van', $$
  SELECT ?predicate, ?object
  WHERE {
    <http://dbpedia.org/resource/Ludwig_van_Beethoven> ?predicate ?object.
  }
$$, '{predicate}');

-- Now query via the created view
SELECT * FROM ludwig_van;