assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:6606  rdfs:subClassOf  DOID:4471  _IRI        
1          0           graph  DOID:6605  rdfs:subClassOf  DOID:4471  _IRI        
1          0           graph  DOID:4471  oio:id           DOID:4471  xsd:string