Question

let itemSchema = new Schema({
  description: String,
  evaluations: [
    {
      evaluation: {
        type: Schema.Types.ObjectId,
        ref: 'evaluation',
        required: true,
        index: true
      },
      selection: {
        type: Schema.Types.ObjectId,
        ref: '????', // How do i reference to 'selection' field here?
        required: true,
        index: true
      }
    }
  ]

let evaluationSchema = new Schema({
  name: {type: String, required: true},
  selections: [
    {
      name: {type: String, required: true }, 
      value: { type: Number, min: 0, max: 15 },
    }
  ],
});

是否可以对selections数组中的项目进行引用？该语法如何编写？在文档中找不到。

Answer 1

请先为两个模式都指定模型的集合名称，然后在引用中输入EvaluationSchema的集合名称，

另一个您不能引用字段，您只能引用模式（引用字段可以使用$ project在mongodb聚合中完成）

let itemSchema = mongoose.Schema({
  description: String,
  evaluations: [
    {
      evaluation: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Eval',
        required: true,
        index: true
      },
      selection: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Eval', // How do i reference to 'selection' field here?
        required: true,
        index: true
      }
    }
  ]
});

mongoose.model("Item", itemSchema);

let evaluationSchema = mongoose.Schema({
  name: {type: String, required: true},
  selections: [
    {
      name: {type: String, required: true }, 
      value: { type: Number, min: 0, max: 15 },
    }
  ],
});
 mongoose.model("Eval", evaluationSchema);

猫鼬，引用数组中的项

1 个答案: