删除猫鼬分页中的重复项

Question

如何通过此json中的“ user_id”属性删除重复的文档：

template<typename T>
struct IVector2 {
    T x, y;

    constexpr IVector2(T x, T y) : //constexpr constructor
        x(x), y(y) { }
};


static constexpr IVector2<int> floors(10,1);  // Initialized constexpr object. Now available at compile time

这是我的代码：

    {
    "searches": [
        {
            "_id": "5ed1fd3f22dfdd1c0b8129c7",
            "word": "hello",
            "user_id": "5ec95f3bbf0ae627713c0625",
            "updatedAt": "2020-05-30T06:29:19.803Z",
            "createdAt": "2020-05-30T06:29:19.803Z",
            "__v": 0
        },
        {
            "_id": "5ed1fd3e22dfdd1c0b8129c6",
            "word": "how",
            "user_id": "5ec95f3bbf0ae627713c0625",
            "updatedAt": "2020-05-30T06:29:18.180Z",
            "createdAt": "2020-05-30T06:29:18.180Z",
            "__v": 0
        },
        {
            "_id": "5ed1fd3622dfdd1c0b8129c4",
            "word": "house",
            "user_id": "5ec95f3bbf0ae627713c0625",
            "updatedAt": "2020-05-30T06:29:10.062Z",
            "createdAt": "2020-05-30T06:29:10.062Z",
            "__v": 0
        },
        {
            "_id": "5ed1fd3c22dfdd1c0b8129c5",
            "word": "hungry",
            "user_id": "9yc95ftyyf0ae627713c5555",
            "updatedAt": "2020-05-30T06:29:10.062Z",
            "createdAt": "2020-05-30T06:29:10.062Z",
            "__v": 0
        }
    ],
    "total": 4,
    "limit": 5,
    "page": 1,
    "pages": 1
}

我要删除重复的文档。有人可以帮忙吗？