节点查找不返回聚合数据

Question

我的 Node 应用程序中有 2 个约会和客户集合，我想显示约会以及与约会相关的用户。我已经设置如下但我没有得到用户作为输出。

var userSchema = new mongoose.Schema({
 firstname: String,
 surname: String,
 email: String,
});

var appointmentSchema = new mongoose.Schema({
 userID: String,
 type: Number,
 time: Date
});

我的查找查询是这样的：-

Appointment.aggregate([
    {
        $match: {"type": 1}  
    },
    {
        $lookup:{
            from: "users",
            localField: "userID",
            foreignField: "_id",
            as: "appointmentUser"
        } 
    }
], function(err,foundAppointmentUser) {
        if(err){
            console.log(err);
        } else {
            console.log(foundAppointmentUser);
        }
    });

mongo中的数据来了，预约数据：-

{
    "_id": {
        "$oid": "5bcc8eac7ac5980bfa365183"
    },
    "userID": "5bb4d1945480e60771ccde5a",
    "type": 1,
    "time": {
        "$date": "2018-10-22T10:00:00.000Z"
    },
    "__v": 0
}

用户数据：

{
    "_id": {
        "$oid": "5bb4d1945480e60771ccde5a"
    },
    "firstname": "Stu",
    "surname": "Test 999",
    "email": "stu@stu.com",
    "created": {
        "$date": "2018-10-03T14:26:28.815Z"
    },
    "__v": 0
}

这是结果：-

[ { _id: 5bcc8eac7ac5980bfa365183,
    userID: '5bb4d1945480e60771ccde5a',
    type: 1,
    time: 2018-10-22T10:00:00.000Z,
    __v: 0,
    appointmentUser: [] } ]

这是检索此类数据的最佳方式吗？另外，为什么我没有收到 appointmentUser 数组下的用户数据？提前致谢。

Answer 1

如下更改架构：仅供参考，Populate

var appointmentSchema = new mongoose.Schema({
 userID: {
   type: Schema.Types.ObjectId,
   ref: 'user'
 },
 type: Number,
 time: Date
});

参考 ID (UserId) 的类型应为 ObjectId 而不是 String。

节点查找不返回聚合数据

Node Lookup not returning aggregated data

lookup

aggregate

mongodb

node.js