Best way to implement Categories and Subcategories with flexible depth in Rails?

Question

I have a Category and Subcategory models in my project. I would like to have many sub-levels in a flexible way. I thought making a self referential "parent" foreign key but I'm not quite sure how to do it. Any ideas? Thanks!

Cat1
    Sub1
        SubSub1
        SubSub2
    Sub2
Cat2
    Sub1
Cat3
    Sub1
    Sub2
        SubSub1

Answer 1

Try the acts_as_tree plug-in

Answer 2

Awesome_nested_set is the best solution, imo, for these types of structures in rails. http://github.com/collectiveidea/awesome_nested_set