class Category < ActiveRecord::Base has_and_belongs_to_many :posts has_and_belongs_to_many :special_posts, :class_name => "Post" has_and_belongs_to_many :other_posts, :class_name => "Post" has_and_belongs_to_many :posts_with_authors_sorted_by_author_id, :class_name => "Post", :include => :authors, :order => "authors.id" has_and_belongs_to_many(:select_testing_posts, :class_name => 'Post', :foreign_key => 'category_id', :association_foreign_key => 'post_id', :select => 'posts.*, 1 as correctness_marker') has_and_belongs_to_many :post_with_conditions, :class_name => 'Post', :conditions => { :title => 'Yet Another Testing Title' } has_and_belongs_to_many :popular_grouped_posts, :class_name => "Post", :group => "posts.type", :having => "sum(comments.post_id) > 2", :include => :comments has_and_belongs_to_many :posts_gruoped_by_title, :class_name => "Post", :group => "title", :select => "title" def self.what_are_you 'a category...' end has_many :categorizations has_many :authors, :through => :categorizations, :select => 'authors.*, categorizations.post_id' end class SpecialCategory < Category def self.what_are_you 'a special category...' end end