Doubts on Mongodb query

Question

I was designing a classifieds web app with the MERN stack. The MongoSchema is as shown below

const UserSchema = new Schema({
    name: {
        type: String,
        required: true
    },
    email: {
        type: String,
        required: true
    },
    password: {
        type: String,
        required: true
    },
    books: [{
        title: { type: String },
        author: { type: String },
        desc: { type: String },
        price: { type: String },
        image: { data: Buffer, contentType: String }
    }],
    date: {
        type: Date,
        default: Date.now
    }
});

So all the other info except the books[] will be available after the initial sign-up, but what I want to do is to update the books array every time the user wishes to post a book for selling.

I'm planning to find the user by id, but I'm not quite sure how to add/append the info to the books array.

tunchunairarko · Accepted Answer · 2021-01-17 16:44:57Z

1

There are some answers to your question already in Stackoverflow. For example: Using Mongoose / MongoDB $addToSet functionality on array of objects

You can do something like this:

UserModel.js

const mongoose = require("mongoose");

const UserSchema = new Schema({
    name: {
        type: String,
        required: true
    },
    email: {
        type: String,
        required: true
    },
    password: {
        type: String,
        required: true
    },
    books: [{
        title: { type: String },
        author: { type: String },
        desc: { type: String },
        price: { type: String },
        image: { data: Buffer, contentType: String }
    }],
    date: {
        type: Date,
        default: Date.now
    }
});
module.exports = User = mongoose.model("user", userSchema);

After that, in your router file you can try something like this for the books array:

const res = await User.updateOne({ email: '[email protected]' }, {'$addToSet':{
'books':{
        title: "Gintama: The Final",
        author: "Sorachi",
        desc: "Final Arc",
        price: "44.99",
        image: "src"
    }}); //addToSet if you don't want any duplicates in your array.

OR

const res = await User.updateOne({ email: '[email protected]' }, {'$push':{
    'books':{
            title: "Gintama: The Final",
            author: "Sorachi",
            desc: "Final Arc",
            price: "44.99",
            image: "src"
        }}); //push if duplicates are okay in your array

edited Jan 17, 2021 at 16:44

answered Jan 17, 2021 at 14:21

tunchunairarko

1111 gold badge1 silver badge8 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Nimrod Over a year ago

Thanks, so addToSet was what I was missing.

tunchunairarko Over a year ago

Yes. In some cases where you might work with quantitative numerical array, you will need push operator.

Collectives™ on Stack Overflow

Doubts on Mongodb query

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related