How can i update the product quantity in cart?

Question

My cart schema

var CartSchema = new mongoose.Schema({
    product: {
        type: mongoose.Schema.Types.ObjectId,
        ref: 'Product'
    },
    totalQty: {
        type: Number,
        default: 0
    },
    totalPrice: {
        type: Number,
        default: 0
    },
    user:{
        type: mongoose.Schema.Types.ObjectId,
        ref: 'User'
    },
    items : Array,
    orderedQty: Number
});

After inserting one record I have got the response

{
    "totalQty": 1,
    "totalPrice": 6500,
    "items": [
        {
            "qty": 1,
            "item": {
                "_id": "5b28d30888afb703508409bb",
                "name": "LENOVO VIBE K5",
                "price": 6500,
                "quantity": 15,
                "imagePath": "https://in.bmscdn.com/showcaseimage/eventimage/hereditary-17-06-2018-10-06-45-907.jpg",
                "description": "This is showcase image from bms",
                "__v": 0
            },
            "price": 6500
        }
    ],
    "_id": "5b2a3da1f4fd65265c8ab477",
    "user": "5b27898931169e074c2dc228",
    "__v": 0
}

I want to update the "qty" inside the items[] array. How can I write the update query?

score 1 · Accepted Answer · answered Jun 20 '18 at 12:46

1

Use the $inc operator:

db.cart.update(
    {_id: ObjectId('5b2a3da1f4fd65265c8ab477'), 'items.item._id': ObjectId('5b28d30888afb703508409bb')},
    {$inc: {"items.$.qty": value}} // Pass your increase value here
)

answered Jun 20 '18 at 12:46

Mạnh Quyết Nguyễn

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Hey @Mạnh Quyết Nguyễn thanks for quick reply but i just confirm that can i access elements of items array using items.item._id? – Sagar Pednekar Jun 20 '18 at 12:53
1

Yes, remember to wrap the nested property inside `'nested.property'`. Find the item you want to increase and use `$inc` to increase the property of that array element – Mạnh Quyết Nguyễn Jun 20 '18 at 12:57
Hey @Mạnh Quyết Nguyễn I have modified my update request like this Cart.update( {_id: '5b2a56656d83d4194cfde63d', 'items.item._id': '5b28d30888afb703508409bb'}, {$inc: {"items.$.qty": 1}},(err,data)=>{ if(err) console.error(err); res.send(data); } // Pass your increase value here ) but in response nothing is getting updated { "n": 0, "nModified": 0, "ok": 1 } – Sagar Pednekar Jun 20 '18 at 13:32
Your IDs are not `ObjectId`? – Mạnh Quyết Nguyễn Jun 20 '18 at 13:34
Yes they are ObjectID – Sagar Pednekar Jun 20 '18 at 13:36
1

I mean, if your IDs are `ObjectId` then you must wrap your id in `ObjectId('5b2a56656d83d4194cfde63d')` like I did – Mạnh Quyết Nguyễn Jun 20 '18 at 13:37
Let us [continue this discussion in chat](https://chat.stackoverflow.com/rooms/173477/discussion-between-sagar-pednekar-and-mnh-quyt-nguyn). – Sagar Pednekar Jun 20 '18 at 13:39
Well I tried that but I am getting "ReferenceError: ObjectId is not defined" – Sagar Pednekar Jun 20 '18 at 13:42

How can i update the product quantity in cart?

1 Answers1