assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:3259  oio:id           DOID:3259  xsd:string  
1          0           graph  DOID:3258  rdfs:subClassOf  DOID:3259  _IRI        
1          0           graph  DOID:4384  rdfs:subClassOf  DOID:3259  _IRI