TutorialREFExample5 List of all Posts PREFIX bibo: <http://purl.org/ontology/bibo/> PREFIX sioc: <http://rdfs.org/sioc/ns#> PREFIX foaf: <http://xmlns.com/foaf/0.1/> PREFIX tutorial: <http://demo.openlinksw.com/schemas/tutorial#> SELECT * WHERE { ?ps a tutorial:Post . ?ps a foaf:Document . ?ps a bibo:Article . optional{?ps bibo:author ?author}. optional{?ps tutorial:belongs_to_section ?belong}. optional{?ps bibo:url ?url}. } Sample Data (Live Query Results) Click *Here* for an Interactive-Web View of Virtuoso Tutorials. Click *Here* for a live SPARQL Query (via SPARQL Protocol) against a collection of Virtuoso Tutorials.