assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:8602  oio:id           DOID:8602  xsd:string  
1          0           graph  DOID:8601  rdfs:subClassOf  DOID:8602  _IRI        
1          0           graph  DOID:9125  rdfs:subClassOf  DOID:8602  _IRI