class Comment < ActiveRecord::Base belongs_to :post def self.what_are_you 'a comment...' end def self.search_by_type(q) self.find(:all, :conditions => ["#{QUOTED_TYPE} = ?", q]) end end class SpecialComment < Comment def self.what_are_you 'a special comment...' end end class VerySpecialComment < Comment def self.what_are_you 'a very special comment...' end end