如何填充其他集合中的文档。具体案例

Question

如何从涉及 2 个集合的查询中获取数据：客户和地址

我需要获取所有客户的所有地址，查询客户集合。

使用 mongoose 这些是 2 个模式：

地址客户：

var Customer = require('./customer');

var Schema = mongoose.Schema;

var addressSchema = Schema({
    address: {
        type: String,
        required: false,
        unique: false
    },
    customer: {
        type: Schema.Types.ObjectId,
        ref: 'Customer'
    }
}, {
    timestamps: true
});

module.exports = mongoose.model('Addresscustomer', addressSchema, 'addressescustomers');

客户：

var Addresscustomer = require ('./addresscustomer');

var Schema = mongoose.Schema;

var customerSchema = Schema({
    name: {
        type: String,
        required: false,
        unique: false
    },
    address: {
        type: Array,
        ref: 'Addresscustomer'
    }
}, {
    timestamps: true
});

module.exports = mongoose.model('Customer', customerSchema, 'customers');

我需要对客户执行查询，我做的是：

Customer.find({}, function (err, customers) {
            Addresscustomer.populate(customers, { path: "address" }, function (err, customers) {
                console.log('Customers: '+ customers);
            });
        });

或者：

var query = Customer.find({}).populate('address');
query.exec(function (err, customers) {
        console.log('Customers: '+ customers);
    });

但是customers集合中的key address没有填写。你能告诉我如何正确设置模式和查询以获得正确的数据吗？

Answer 1

您也可以在数组字段上使用 $lookup to populate address reference. Since Mongo 3.4 $lookup works。

db.customers.aggregate([
    { "$lookup": {
       "from": "addressescustomers",
       "localField": "address",
       "foreignField": "_id",
       "as": "addr"
    }}
])

如何填充其他集合中的文档。具体案例

How to populate documents from other collection. Specific case

mongoose

mongodb

mongoose-populate