\set VERBOSITY terse --------------------------------- Wikidata (Blazegraph) --------------------------------- CREATE SERVER wikidata FOREIGN DATA WRAPPER rdf_fdw OPTIONS (endpoint 'https://query.wikidata.org/sparql', connect_retry '0'); -- IRI description SELECT subject, predicate, object FROM sparql.describe('wikidata', 'DESCRIBE ') ORDER BY object::text COLLATE "C"; -- graph pattern description SELECT subject, predicate, object FROM sparql.describe('wikidata',' PREFIX wdt: PREFIX wd: DESCRIBE ?s WHERE { ?s wdt:P734 wd:Q59853; wdt:P19 wd:Q84 ; schema:description ?d FILTER(STR(?d) = "British astronomer") }') WHERE predicate = '' AND object = '"Harold Spencer Jones"@en' ORDER BY object::text COLLATE "C"; SELECT subject, predicate, object FROM sparql.describe('wikidata', 'DESCRIBE ', false) WHERE predicate IN ('','') ORDER BY object::text COLLATE "C"; SELECT subject, predicate, object FROM sparql.describe('wikidata', 'DESCRIBE ', true) WHERE predicate IN ('','') ORDER BY object::text COLLATE "C"; SELECT subject, predicate, object FROM sparql.describe( query =>'describe wd:Q471896', server => 'wikidata', base_uri => 'http://test.base.uri/', raw_literal => false) WHERE predicate = '' ORDER BY object::text COLLATE "C"; -- empty server SELECT * FROM sparql.describe('', 'DESCRIBE '); -- empty DESCRIBE pattern SELECT * FROM sparql.describe('wikidata', ''); -- empty SERVER and DESCRIBE pattern SELECT * FROM sparql.describe('', ''); -- NULL DESCRIBE pattern SELECT * FROM sparql.describe('wikidata', NULL); -- NULL SERVER SELECT * FROM sparql.describe(NULL, 'DESCRIBE '); -- NULL SERVER and DESCRIBE pattern SELECT * FROM sparql.describe(NULL, NULL); -- invalid SERVER SELECT * FROM sparql.describe('invalid', 'DESCRIBE '); SELECT * FROM sparql.describe(' ', 'DESCRIBE '); -- invalid DESCRIBE pattern SELECT * FROM sparql.describe('wikidata', 'invalid'); SELECT * FROM sparql.describe('wikidata', ' '); SELECT * FROM sparql.describe('wikidata', 'DESCRIBE http://www.wikidata.org/entity/Q61308849'); -- missing < > -- DESCRIBE pattern with a blank node SELECT * FROM sparql.describe('wikidata', '_:bnode1'); SELECT * FROM sparql.describe('wikidata', 'DESCRIBE _:bnode1'); -- malformed entity IRI SELECT * FROM sparql.describe('wikidata', 'DESCRIBE '); -- SELECT query SELECT * FROM sparql.describe('wikidata', 'SELECT ?s ?p ?o WHERE {?s ?p ?o}'); DROP SERVER wikidata; ----------------------------------- Virtuoso (DBpedia) ----------------------------------- CREATE SERVER dbpedia FOREIGN DATA WRAPPER rdf_fdw OPTIONS (endpoint 'https://dbpedia.org/sparql'); -- IRI description SELECT subject, predicate, object FROM sparql.describe('dbpedia','dEsCrIBe ') ORDER BY subject::text, object::text COLLATE "C"; DROP SERVER dbpedia;