How many players participated in the 2004-05 FC Barcelona season?
SELECT DISTINCT COUNT(?uri) WHERE { <http://dbpedia.org/resource/2004–05_FC_Barcelona_season> <http://dbpedia.org/property/name> ?uri  . ?uri <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dbpedia.org/ontology/SoccerPlayer>}
2004–05_FC_Barcelona_season