assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:8251  rdfs:subClassOf  DOID:3250  _IRI        
1          0           graph  DOID:7463  rdfs:subClassOf  DOID:3250  _IRI        
1          0           graph  DOID:3250  oio:id           DOID:3250  xsd:string