如何对嵌套结构的Mongodb查询进行排序

我有一堵墙和几条关于墙的评论

{
    "Wall_id": "wall002",
    "user_id": "user002",
    "message_author": "AuthorB",
    "wall_message": "content:TRY",
    "posted_on": "24/8/15",
    "author_id": "A002",
    "path_to_files": ["home/path"],
    "wall_recepients":["user002","user003","user004","user005","user006"],
    "w_timestamp": 678,
    "Comments": [
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 700
       },
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 1000
       }
    ]
}

我需要一个查询，它可以对基于w_时间戳排序的墙元素进行排序，并对基于c_时间戳排序的每个墙的注释数组进行排序

我正在使用pymongo并尝试

searchUser = "user002"
result = post.find({"wall_recepients":{"$in":[searchUser]}}).sort([["post.w_timestamp",DESCENDING],["post.Comments.c_timestamp",DESCENDING]])

下降就是下降

提前谢谢！ 预期产出：

给定一个用户id，获取wall\u Recipients包含该用户id的所有墙项目，如

[

{
    "Wall_id": "wall002",
    "user_id": "user002",
    "message_author": "AuthorB",
    "wall_message": "content:TRY",
    "posted_on": "24/8/15",
    "author_id": "A002",
    "path_to_files": ["home/path"],
    "wall_recepients":["user002","user003","user004","user005","user006"],
    "w_timestamp": 678,
    "Comments": [
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 700
       },
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 1000
       }
    ]
},

{
    "Wall_id": "wall001",
    "user_id": "user002",
    "message_author": "AuthorB",
    "wall_message": "content:TRY",
    "posted_on": "24/8/15",
    "author_id": "A002",
    "path_to_files": ["home/path"],
    "wall_recepients":["user002","user003","user004","user005","user006"],
    "w_timestamp": 666,
    "Comments": [
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 124
       },
        {
            "comment_id": "cmt001",
            "Wall_id": "wall001",
            "user_id": "user001",
            "pathtofile": "[home/doc/file]",
            "comment": "try 2",
            "profile_pic": "home2/pic.jpg",
            "user_name": "user2",
            "c_timestamp": 246
       }
    ]
}


]

---

您的预期输出是什么？我只希望每个墙id按时间戳降序排序，并且在每个墙id中，我还希望注释按时间戳排序（ASC或DESC）。请使用您问题上的链接添加预期结果谢谢，我已添加预期输出，这有帮助吗？按评论排序是什么意思？是否要对

注释

数组进行排序？如果是，您为什么需要它？您的预期输出是什么？我只希望每个墙id按时间戳降序排序，并且在每个墙id中，我还希望注释按时间戳排序（ASC或DESC）。请使用您问题上的链接添加预期结果谢谢，我已添加预期输出，这有帮助吗？按评论排序是什么意思？是否要对

注释

数组进行排序？如果是，为什么需要？