具有单表继承STI和has_and_belongs_to_manyHABTM关联的Bug

问题描述

| 使用Rails 3.0.7，并具有以下4个模型：

class User < ActiveRecord::Base
end

class Administrator < User
  has_and_belongs_to_many :clients
end

class Client < ActiveRecord::Base
  has_and_belongs_to_many :administrators
  has_and_belongs_to_many :meetings
end

class Meeting < ActiveRecord::Base
  has_and_belongs_to_many :clients

  def self.foo
    self.joins(:clients => :administrators)
  end
end

致电：

Meeting.foo.to_sql

产生：

SELECT meetings.*
FROM meetings
INNER JOIN clients_meetings ON clients_meetings.event_id = meetings.id
INNER JOIN clients ON clients.id = clients_meetings.child_id
INNER JOIN clients_administrators ON clients_administrators.child_id = clients.id
INNER JOIN users ON users.type = \'Administrator\'

但似乎好像错过了\“ clients_administrators \”和\“ users \”之间的最终联接关系。我认为sql的最后一行应显示为：

INNER JOIN users ON users.id = clients_administrators.user_id
WHERE users.type = \'Administrator\'

这是错误吗？还是我误会了什么？ 谢谢     

解决方法

        这似乎是一个错误，但已在Rails 3.1中解决。