I am trying to run the sparql query against northwind tutorial database and i get this error: How do i correct this error?
000012: com.complexible.stardog.plan.eval.ExecutionException: com.complexible.common.rdf.query.parser.sparql.ast.VisitorException: QName 'foaf:title' uses an undefined prefix
I am running the following query:
SELECT
?label
?lastName
?firstName
?title
WHERE {
?emp a :Employee ;
rdfs:label ?label ;
foaf:title ?title ;
foaf:lastName ?lastName ;
foaf:firstName ?firstName .
}
Thank you in advance for your help