Pymong中存在Check字段

Question

我有这样的收藏：

{ 
  "_id":"1321464"
  "Sex":"Male"
  "Age":"20" 
  "City":"Toronto" #Maybe this field are not present.
}

我想找到我所有的文件与字段“城市”不存在。 我试着：

collection.find({"sex":"Male"},{"City":{"$exists": False}},{'Age': 1, '_id':0})

我有一条错误信息：

File "/usr/local/lib/python2.7/dist-packages/pymongo/collection.py", line 1239, in find
    return Cursor(self, *args, **kwargs)
  File "/usr/local/lib/python2.7/dist-packages/pymongo/cursor.py", line 125, in __init__
    raise TypeError("skip must be an instance of int")
TypeError: skip must be an instance of int

Answer 1

向find方法传递三个参数。我想你只想通过一个过滤器和一个投影。试试这个：

collection.find({"sex":"Male", "City":{"$exists": False}},{'Age': 1, '_id':0})