assertion  retraction  graph  subject    predicate        object     datatype    annotation
1          0           graph  DOID:1733  rdfs:subClassOf  DOID:2113  _IRI        
1          0           graph  DOID:2113  oio:id           DOID:2113  xsd:string  
1          0           graph  DOID:9965  rdfs:subClassOf  DOID:2113  _IRI