ActiveRecord::Associations::ClassMethods

Ruby on Rails 4.1.16 Module ActiveRecord::Associations::ClassMethods activerecord/lib/active_record/associations.rb Associations are a set of macro-like class methods for tying objects together through foreign keys. They express relationships like “Project has one Project Manager” or “Project belongs to a Portfolio”. Each macro adds a number of methods to the class which are specialized according

[sessan]

ポリモーフィック関連は、joinsが使われなければpreloadできるらしい。