pvin / photoblog

This example tells about db relationship between gallery-photo-comment. The association is similar to the Gallery/Photo relationship with one addition: A comment belongs to a single photo, a photo can have many comments, and a gallery has many comments through its photos.(one gallery has many photos, one photo has many comments, gallery has many comments through photos)(http://www.andrewdenhertog.com/ruby-on-rails/creating-model-associations-in-rails/)