如何填充 Mongoose 数组中的字段？

Question

我有一个这样的集合架构：

const PrescriptionSchema = new Schema({
    patientId:{type: mongoose.Schema.ObjectId, ref: 'User'},
    prescriptionName: String,
    prescriptionNote: String,
    prescriptionDate: Date,
    diseaseId: {type: mongoose.Schema.ObjectId, ref: 'Diseases'},
    drugs: [{
        drugcateId:{type: mongoose.Schema.ObjectId, ref: 'DrugCategory'},
        quantity: Number,
        howtouse: String
    }],
    is_deleted: {type: Boolean, default: false},
    createdBy: {type: mongoose.Schema.ObjectId, ref: 'User'}
}, {
        timestamps: true,
        collection: 'prescriptions'
    }
);
export default mongoose.model('prescriptions', PrescriptionSchema );

请注意，在这个集合中我有一组“药物”，这是我从 'DrugCategory' 获得的一组药物，在每种药物中我都有数量和使用方法..所以我把它分组(drugCateId, quantity, howtouse) 在药物数组中。当我找到处方时，我想将 drugCateId 填充到 drugs 数组中。我该怎么做？以下是我当前的代码：

async findOne(req, res){
        const { id } = req.params;
       await Prescriptions.
            findOne({ is_deleted: false, _id: id}).
             .populate(
               {
                 path: 'drugs',
                   populate: {
                     path: 'drugCateId',
                     model: 'DrugCategory'
                   }
               }).
            exec(function (err, data) {
              if (err) return handleError(err);
              res.send(data)
            });
      }

但这行不通。以下是我的结果：

{
    "is_deleted": false,
    "_id": "5f32768a06693a520806717d",
    "patientId": "5c80930d447df7735138693e",
    "prescriptionName": "Prescription for you",
    "prescriptionNote": "Please drink follow doctor",
    "prescriptionDate": "2020-07-08T00:00:00.000Z",
    "diseaseId": "5f22a6d600980c081ca9e14f",
    "drugs": [
        {
            "_id": "5f32768a06693a5208067181",
            "drugcateId": "5f23deca04e3150a48632229", // How can I populate this one?
            "quantity": 10,
            "howtouse": "drink 2 times after meal everyday"
        },
        {
            "_id": "5f32768a06693a5208067180",
            "drugcateId": "5f23deca04e3150a48632233", // How can I populate this one?
            "quantity": 10,
            "howtouse": "drink 2 times after meal everyday"
        },
        {
            "_id": "5f32768a06693a520806717f",
            "drugcateId": "5f23deca04e3150a48632234", // How can I populate this one?
            "quantity": 10,
            "howtouse": "drink 2 times after meal everyday"
        },
        {
            "_id": "5f32768a06693a520806717e",
            "drugcateId": "5f23deca04e3150a4863224a", // How can I populate this one?
            "quantity": 10,
            "howtouse": "drink 2 times after meal everyday"
        }
    ],
    "createdBy": "5d1cd947231ceb95b8838c1b",
    "createdAt": "2020-08-11T10:44:26.842Z",
    "updatedAt": "2020-08-11T10:44:26.842Z",
    "__v": 0
}

希望你理解我的问题，请看一看。谢谢

Answer 1

你看起来很接近，但一定要提供正确的路径：

.populate({
   path: 'drugcateId',
   model: 'DrugCategory'
})

将 drugCateId 更改为 drugcateId。

此外，您应该能够直接填充 DrugCategory。

Answer 2

您当前的版本与您的架构不匹配。它建议您同时填充 drugs 和 drugs.drugcateId。但是这里 drugs 是直接嵌入的，而不是对另一个集合中文档的引用，所以不可能 populate():

 .populate({
     path: 'drugs',  // this assumes drugs are objectIds: [{ type: ObjectId, ref: 'Drug' }]
     populate: {
       path: 'drugCateId',
       model: 'DrugCategory'
     }
   })

相反，您应该能够对数组使用 dot-notation：

.populate({ path: "drugs.drugcateId" })

或短

.populate("drugs.drugcateId")

Answer 3

感谢您的回复。我有一个错误，我的模型是“drugcate”，但在我的填充命令中是“drugCate”。我已经将我的模型更改为“drugCate”并且下面的查询有效。

populate({ path: 'drugs.drugCateId', 
   populate: {path: 'drugs.drugCateId'}
})

谢谢

如何填充 Mongoose 数组中的字段？

How to populate an field in array of Mongooese?

mongoose

mongodb

mongodb-query

mongoose-populate

mongoose-schema