mongodb: array contains and array don't contains

How do I check if list1 contains A and list2 开发者_如何学Pythondon't contains A? both list1 and list2 are array (list2 can be empty or not set)

I tried query:

{
  'list1':'A', 
  'list2':{ '$ne':'A'}
}

but I'm getting results with list1 contains A and list2 contains A. if I remove 'list2':{ '$ne':'A'} ...results is the same, likes list2 part don't metter

strange ...am I doing something wrong?

---

I was updating it wrong. Should be this:

db.test.update({ _id: X }, {'$push': {"a2": 'A'}});

Or this:

db.test.update({ _id: X }, {'$set': {"a2": ['A']}});

the document looks like this:

{ "_id" : ObjectId("4dbacb40696b6ede04c5ef97"), "a1" : [ "A" ], "a2" :
{ "0" : "A" } }

Where it's correct that {"0": "A"} is not equal to A