查找/或实现正确的mongoDb方法以查找和更新子文档[duplicate]时遇到困难

Question

我正在尝试根据子文档的Id和父文档的Id更新子文档中的特定字段。我是新手，所以我可能误会了mongoDb文档，但据我所知，findOneAndUpdate应该可以工作。我还尝试了just update、updateOne以及FindByIdandUpdate。我尝试的任何操作都没有成功更新我的对象。

{
    "_id": {
        "$oid": "5c97cf50cc81525a75eb6c19"
    },
    "email": "[e-mail]",
    "password": "$2b$10$6ixbu2Ka.Zj0eE5kF21MLO6CiMblgu4D6IHiC7Ta52o.cZFMNw1Mm",
    "__v": 0,
    "savedBeers": [
        {
            "id": 2,
            "comment": null,
            "rating": 0
        },
        {
            "id": 4,
            "comment": null,
            "rating": 0
        }
    ]
}

前端：

function addRating(beerId, ratingValue){
    let userId= localStorage.userId
    console.log(beerId, userId, ratingValue);
    $.ajax({
        type: "PUT",
        url: `/user/${userId}/${beerId}/${ratingValue}`,
        success: addRatingSuccess,
        error: addRatingError
    });
    function addRatingSuccess(response) {
        console.log("added", response);
    }
    function addRatingError() {
        console.log("error");    
    }
}

后端UserController.js：

 addRating:(req,res)=>{
            console.log(req.params);
            req.params.beerId = parseInt(req.params.beerId)
            req.params.ratingValue = parseInt(req.params.ratingValue)
            db.User.findOneAndUpdate(
                 {_id: ObjectId(req.params.userId), "savedBeers.id": req.params.beerId },
                { $set: { 'savedBeers.$.rating' : req.params.ratingValue } },
                {new:true})
                .exec(function (err, doc){
                    if (err){
                        console.log(err);
                        res.json({
                            "error": err
                        })
                    } else {
                        console.log(doc);
                        res.json({
                            doc
                        })
                    }
                }) 
        }

这是我在前端得到的回应：

added 
{doc: {…}}
doc:
email: "[e-mail]"
savedBeers: Array(2)
0: {id: 2, comment: null, rating: 0}
1: {id: 4, comment: null, rating: 0}
length: 2
__proto__: Array(0)
__v: 0
_id: "5c97cf50cc81525a75eb6c19"
__proto__: Object
__proto__: Object

{ userId: '5c97cf50cc81525a75eb6c19', beerId: 4, ratingValue: 3 }
{ savedBeers:
   [ { id: 2, comment: null, rating: 0 },
     { id: 4, comment: null, rating: 0 } ],
  _id: 5c97cf50cc81525a75eb6c19,
  email: '[e-mail]',
  __v: 0 }

Answer 1

在“{$SET：{”Saved Beers.$“：Req.Params.RatingValue}”中的“SavedBeers.$”后面似乎缺少了“.Rating”

因此该行应为“{$SET：{”Saved Beers.$.Rating“：Req.Params.RatingValue}”