Rails 4 Inner Join在同一张桌子上

Question

在Rails 4应用程序中，我有以下关联：

User has_many :bookings
Booking belongs_to :client, class_name: "User"

我正在尝试通过表格加入以获取预订和客户端：

User.joins("INNER JOIN bookings on users.id = bookings.user_id").joins("INNER JOIN users on bookings.client_id = users.id") 

返回：

PG::DuplicateAlias: ERROR:  table name "users" specified more than once

是否有解决方案来获取2个关联？

Answer 1

尝试

User.joins("INNER JOIN bookings on users.id = bookings.user_id").joins("INNER JOIN users AS bookings_user on bookings.client_id = bookings_user.id")

请注意users AS bookings_user