MongoDB python嵌套对象

Question

There is such a structure

PLAYER_DEFAULT = {
"_id": Inc(PlayersDB),
"mail": "test@gmail.com",
"password": "123456",
"token": uuid4().hex,
"username": "applet",
"user_info":
    {
        "show_name" : "Hero",
        "rate_us": 20000,
        "rating": 300,
        "gcg": "",
        "ration":0,
        "items":
            [
                {"id":1, "item_type":"socket",      "name":"aEveA", "data":{"level":1, "stat":"AVA"}},
                {"id":2, "item_type":"socket",      "name":"aEveA", "data":{"level":4, "stat":"AVA"}},
                {"id":3, "item_type":"socket",      "name":"Hestos", "data":{"level":9, "stat":"Hest"}},
                {"id":4, "item_type":"user", "name":"AAACZX",   "data":{"expr":1000}},
                {"id":5, "item_type":"user", "name":"AAAAZZZCX",   "data":        {"expr":1000}}
               ]
        } 
}

I am writing in Python 3.5, PyMongo.

1. I need delete one or more objects in ["user_info"]["items"]
2. I need update one or more objects in ["user_info"]["items"]
3. I need get value by value, example PLAYER_DEFAULT.find({}, {"item_type","user"})
4. How to operate with embedded objects? -> example PLAYER_DEFAULT.find({"0.user_info.items.id":1}) < - how remove \\ update 1 element in items?

Answer 1

1. To delete one or more objects in ["user_info"]["items"] : Use $pull operator. Example : db.collection_name.update({},{'$pull': {'user_info.items': {'id': 'id of the item'}}})

2. To update one or more objects in ["user_info"]["items"] : Example : db.collection_name.update({'user_info.items.id':'id to change'},{'$set':{'user_info.items.$.'field to change'':'new field value'}})

for third and fourth query, use mongo projection('$') operator.That will do your job.