Push to array in Mongodb-CodePudding

How do I push to the inner arrays in MongoDB?

[
    { emoji1: ['user19', 'user20', 'user21']},
    { emoji5: ['user12', 'user13', 'user14']},
    { emoji9: ['user29', 'user30', 'user34']}
]

I tried:

await Post
    .updateOne({ _id: postID }, { 
        $push: {
            [`reactions[0].emoji1`]: 'random user'
    }
})

...where Post is my Mongoose Schema and "reactions" is the array above. I think I am doing something wrong in $push.

The result should be:

[
    { emoji1: ['user19', 'user20', 'user21', 'random user']},
    { emoji5: ['user12', 'user13', 'user14']},
    { emoji9: ['user29', 'user30', 'user34']}
]

Thanks in advance!

CodePudding user response：

You can use this query:

db.collection.update({
  id: 1,
  "reactions.emoji1": {
    "$exists": true
  }
},
{
  "$push": {
    "reactions.$.emoji1": "random user"
  }
})

Example here