node.js - 如何在 mongodb Node.js 中使用字符串字段填充 _id 字段？

Question

我有两个集合用户和评论。在用户中有字段:

const user = mongoose.Schema({
    _id                 :("In the form of ObjectID"), 
                      //ObjectId("5a19086e0664e832842f2c24")
    user_name                   :{type: String},
    password                    : {type: String}
});

以及评论收集:

const comments = mongoose.Schema({
    user_id                     :{type: String},
                //"5a19086e0664e832842f2c24" this is user's _id
    comment                    : {type: String}
});

现在我想知道如何用评论集合中字符串类型的用户_id 填充这2 个集合。提前谢谢您

Answer 1

我认为您已经可以使用 String 来填充 ObjectId，如下所示:

const user = mongoose.Schema({
    user_name                   : {type: String},
    password                    : {type: String}
}); // users._id will natively be an ObjectId 

const comments = mongoose.Schema({
    user_id                    : {type: String, ref:'users'}, // user_id has to be referenced with your "users" model
    comment                    : {type: String}
});

Comment.find({}).populate('user_id').exec();

希望有帮助。