MongoDB, I want to update all arrays inside nested array

Question

I want to add "3" to all "seenBy" array which is inside "Conversation" array.

{
  _id : 1,
  name : "name",
  email : "email",
  conversation : [
      {
        message : "Hai",
        seenBy : [1,2]
      },
      {
        message : "Hai",
        seenBy : [1,2]
      },
      {
        message : "Hai",
        seenBy : [1,2]
      }
  ]
}

Expected result :

{
  name : "name",
  email : "email",
  conversation : [
      {
        message : "Hai",
        seenBy : [1,2,3]
      },
      {
        message : "Hai",
        seenBy : [1,2,3]
      },
      {
        message : "Hai",
        seenBy : [1,2,3]
      }
  ]
}

My code :

DB.Users.update({_id : 1}, {$addToSet : {"conversation.$[].seenBy" : 3}}, {}, function(err, result){
console.log(err);
console.log(result)
})

I get this error :

MongoError: cannot use the part (conversation of conversation.$[].seenBy) to traverse the element

Thanks in advance.

Rahul Raj · Accepted Answer · 2018-04-06 14:04:24Z

1

You're not specifying _id field in the data set u mentioned:

{
  name : "name",
  email : "email",
  conversation : [
  {
    message : "Hai",
    seenBy : [1,2]
  },
  {
    message : "Hai",
    seenBy : [1,2]
  },
  {
    message : "Hai",
    seenBy : [1,2]
  }
 ]
}

So, MongoDB add an ObjectID automatically, so you need to specify that. _id:1 will work if u have the specified _id in the DB. I'm getting proper output using your above query:

So, the issue is with your mongoose code and not with the Mongo query.

answered Apr 6, 2018 at 14:04

Rahul Raj

3,4698 gold badges42 silver badges67 bronze badges

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

4 Comments

ŞükSefHam Over a year ago

thomas get truw answer and run away:D

thomas Over a year ago

Sorry. Check my "Update" query. I am using "_id" to update the document.

thomas Over a year ago

Not funny :P @ŞükranEken

thomas Over a year ago

I am using mongoose and i don't know why its throwing error. @Rahul Raj

Muhammad Usman · Accepted Answer · 2018-04-06 14:11:58Z

0

This is the way you can access nested array in document and push in it

Something like

db.Users.update(
{},
{ "$push": {"conversation.$[].seenBy": 3}}
)

Note. This will add 3 to all of your documents. You can add any filter based on your requirements

answered Apr 6, 2018 at 14:11

Muhammad Usman

10.1k26 silver badges41 bronze badges

Collectives™ on Stack Overflow

MongoDB, I want to update all arrays inside nested array

2 Answers 2

4 Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

4 Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related