The following python code causes a segmentation fault:

>>> from bson import ObjectId
>>> from pymongo import MongoClient
>>> client = MongoClient(host='myhost', tz_aware=True)
>>> data = client['dbname']['data']
>>> data.find_one(

{'_id': ObjectId('5127a845c6e8fc660bcbf2f3')}

)
Segmentation fault

This issue seems to be caused by a corrupted document (querying for other documents does not cause any problems), to be precise a DBRef field seems to be broken. The Mongo shell is able to query for this document and displays:

> db.data.find({_id: ObjectId('5127a845c6e8fc660bcbf2f3')},

{parentId: 1}

)

{ "_id" : ObjectId("5127a845c6e8fc660bcbf2f3"), "parentId" : DBRef("data", undefined) }

Is there any way to display the internal structur and its values of the field parentId, i.e. to display the document without converting it to a DBRef object?