com.mongodb.MongoCommandException: Command failed with error 48 (NamespaceExists): 'target namespace exists' on server %mongohostport%. The full response is {"ok": 0.0, "errmsg": "target namespace exists", "code": 48, "codeName": "NamespaceExists"}
[ { "_id": <ObjectID>, "a": 1 } ]
[ { "_id": <ObjectID>, "a": 2 } ]