Return only one field from MongoDB query

Suppose my document looks like this

{
    "_id": 2,
    "Name": "Abcd",
    "Connected": [1,3]
}

Now, I want to retrieve the array [1,3] via the _id or Name. The purpose is to save this array into a JavaScript array.

Hence I tried using db.myCollection.find({"_id":2},{"Connected":1}) but it return a document again moreover with _id still there like this

{ "_id" : 2, "Connected" : [ 1, 3 ] }

How can I retrieve only that array?

>Solution :

You can optionally remove the ID from your result, by setting it to 0 in the projection:

db.myCollection.find({"_id":2},{"Connected":1, "_id":0})

The ID field is the only field that can be excluded in projections while other fields are included.

If you want to get the Connected field directly, you can use findOne:

db.myCollection.findOne({"_id":2}, {"Connected":1, "_id":0}).Connected