insert id into type array mongodb-CodePudding

My mongodb collection login is structured as so:

email: "[email protected]"
password: "password"
full_name: "John Doe"
list_of_docs_bought: Array
   0: "g81h8"
   1: "fursr"

now, in my code, what I want to do is insert a new id into the list_of_docs_bought array. My code is as follows:

let collection = database.collection('login')
let doc = collection.updateOne({ email: req.session.username }, {$set: { list_of_docs_bought: '2xx729' }})

however, this isn't going to work because I need to essentially insert a new id into there, not update it. But if I use .insert(), I am not sure if that is going to work because it will insert a totally new record instead of just into the array. Can anyone offer some help?

CodePudding user response：

You can use upsert which does exactly what you need.

Explanation below is taken from the official docs.

Creates a new document if no documents match the filter. For more details see upsert behavior.

Updates a single document that matches the filter.

So you would need to change your code to that:

let doc = collection.updateOne({ email: req.session.username }, {$push: { list_of_docs_bought: '2xx729' }}, { upsert: true })

Edit: You need to use the $push operator in order to add an element in an array. The $set operator will just overwrite it.