assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:9297  oio:id           DOID:9297  xsd:string  
1          0           graph  DOID:8564  rdfs:subClassOf  DOID:9297  _IRI        
1          0           graph  DOID:8661  rdfs:subClassOf  DOID:9297  _IRI