Question

我有以下3种模式：“付款”，“程序”和“订阅”。

const paymentSchema = new Schema({
    toUser: {type:Schema.Types.ObjectId, ref: 'User'},
    subscription: {type:Schema.Types.ObjectId, ref: 'Subscription', default: null }
});

const subscriptionSchema = new Schema({
    user: {type:Schema.Types.ObjectId, ref: 'User'}, // user who is subscribed to program
    program: {type:Schema.Types.ObjectId, ref: 'Program'}
});

const Program = new Schema({
            title: { type: String, required: true, max: [50, 'Too long, max is 50 characters']},
            country: { type: String, required: true },
            //Some more properties...
            //...
            category: { type: String, required: true, lowercase: true },
);

我想获得所有已登录用户等于“ toUser”属性的付款，在付款内填充订阅，然后在预订内填充程序，最后按程序分组。听起来令人困惑，但管道可能是这样的

（获取付款给用户）=>（填充Payment.subscription）=>（填充Payment.subscription.program）=>（按Payment.subscription.program分组）

但是，我对如何使用汇总来实现这一点感到困惑，因为付款仅包含对“订阅”的引用，而“订阅”包含对“程序”的引用

我试图做这样的事情，每次都为相应的子文档查找两次

const groupedPayments = await Payment.aggregate([
        {$match: {$and: [{"toUser": user._id},{"booking": null}]}},
        {$lookup:
            {
                from: "subscription",
                localField: "subscription",
                foreignField: "id",
                as: "subscriptions"
            }
        },
        {$lookup:
            {
                from: "program",
                localField: "program",
                foreignField: "id",
                as: "program"
            }
        },
        {$group: {_id: "$subscription.program"}}
    ])

我想以类似于以下格式获取所有数据：

{ "_id" : { "program" : "Title 1"}, 
  "payments" : [
        { "payment_1": {//some data//},
        { "payment_2": {//some data//},
        { "payment_X": {//some data//}
    ]
},
{ "_id" : { "program" : "Title 2"}, 
  "payments" : [
        { "payment_1": {//some data//},
        { "payment_2": {//some data//},
        { "payment_X": {//some data//}
    ]
},
{ "_id" : { "program" : "Title 3"}, 
  "payments" : [
        { "payment_1": {//some data//},
        { "payment_2": {//some data//},
        { "payment_X": {//some data//}
    ]
},

如何在单个聚合查询中填充子文档中的子文档并按子文档分组？

0 个答案: