When I used roqet to perform a SPARQL query, I get this error:
roqet: Error - - The namespace prefix in "sbd:Dataset" was not declared.
roqet: Error - URI file:///home/egonw/var/Projects/umlab/sbd-data-landscape-data/aop/aopwiki-datasets.ttl:2 - Failed to convert qname sbd:Dataset to URI
roqet: Error - URI file:///home/egonw/var/Projects/umlab/sbd-data-landscape-data/aop/aopwiki-datasets.ttl:2 - syntax error, unexpected $end
roqet: Query execution failed
When I used
roqet
to perform a SPARQL query, I get this error: