Can a MongoDB collection have inside it another collection?

Question

I need to store a recursive tree structure. A linked list.
So all the objects are the same. Each has a pointer to a parent object and each has an array of child objects.

Answer 1

You cant store collections in collections. But you can store ids that reference objects in other collections. You would have to resolve the id to the document or element and then if that element stores more ids you would need to resolve those on and on. Documents are meant to be rich and duplicate data but in the docs they do explain that instead of embedding you can just use ids