Mongodb Mongoose基于另一个字段动态引用进行填充

我有两位老师

const TeacherSchema = mongoose.Schema(
  {
    name:String
    _id: ObjectId
})

学生

const StudentSchema = mongoose.Schema(
  {
    name:String
    _id: ObjectId
})

我有注释模式

const CommentSchema = mongoose.Schema(
  {
    description: String,
    user_type:String  // Student or Teacher
    user_id: ObjectId
})

---

如何基于

user\u type

填充

CommentSchema

，例如

如果user\u type===Teacher

user\u id是from

TeacherSchema

在这种情况下，您可以使用populatewith。例如：

const CommentSchema = mongoose.Schema({
  description: String,
  user_type: String  // Student or Teacher
  user_id: {
    type: Schema.Types.ObjectId,
    refPath: 'user_type'
  }
})