Doing

_db.GetCollection<TEntity>(typeof(TEntity).Name).AsQueryable().Count()

results in

Command aggregate failed: not authorized on DB to execute command { aggregate: "Customer", pipeline: [ { $sort:

{ lastname: 1, companyShortTitle: 1 }

}, { $group: { _id: 1, __result:

{ $sum: 1 }

} } ], cursor: {} }.

The user that uses the conncection has dbAdmin, dbOwner and readWrite roles.