assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:2825  oio:id           DOID:2825  xsd:string  
1          0           graph  DOID:1352  rdfs:subClassOf  DOID:2825  _IRI        
1          0           graph  DOID:2163  rdfs:subClassOf  DOID:2825  _IRI