gistfile1.rb

class Book < ActiveRecord::Base
  belongs_to :publisher
  belongs_to :author, :select => [:id, :name], :conditions => "name != 'jax'"
  belongs_to :another, :class_name => "SomeModel"

  has_many :revisions
  has_many :editors, :through => :revisions
  
  has_one :something

  validates_length_of :title, :within => 1..5
end