使用 mongo db 查询用户的推荐

Question

I want to create a referral system with nodejs and mongoose, and I need help with the mongodb queries

the user object:

    {

    email: String,
    referredBy: ObjectId,
    points: Int,
    _id: ObjectId
    
    }

First query: each time that a user wins points I want to add points to his main referral, and then to that user referral and the same with that user, this system has 3 level of referrals

Second query: get all referred users that a user referred to (this would be easy it was just one level (doing

this.user.find({referredBy: userId}))

)

but I need to get all 3 levels, first all user that user referred to and the same with those users and the same with these users

also with this second query would it be possible to add some field to each level?

like all referred users of first level to have a 'level': 'first' so i could later distinguish them

Answer 1

First question:

Process each user in a loop in your application. Retrieve parent user, update parent, retrieve parent's parent, etc.

Second question:

Use $lookup and $unwind to join users onto themselves as many times as is necessary.