MongoDB: How to get distinct list of sub-document field values?

Question

Let\'s say I have the following documents in collection:

{
   \"family\": \"Smith\",
   \"children\": [
        {
            \"child_name\": \"John\"
               


        

Answer 1

You can just do:

db.collection.distinct("children.child_name");

In your case it returns:

[ "John", "Anna", "Kevin" ]