1
我有一個應用程序,我們只是從2.1.0升級到2.3.10。升級之後,以前工作的關聯擴展會導致失敗。這裏是關於模型的擴展代碼:關聯擴展不再適用於Rails 2.3.10
Class Classroom
has_many :registrations
has_many :students, :through => :registrations, :uniq => true do
def in_group(a_group)
if a_driver
scoped(:conditions => ['registrations.group_id = ?', a_group])
else
in_no_group
end
end
def in_no_group
scoped(:conditions => 'registrations.group_id is null')
end
end
end
這是我的實際問題的簡化模型,但基本上我曾經是能夠做到
classroom.students.in_group(honor_students)
此不再起作用,用下面的輸出:
classroom.students.in_group(honor_students)
ActiveRecord::StatementInvalid: Mysql::Error: Unknown column 'registrations.group_id' in 'where clause': SELECT * FROM `students` WHERE (registrations.group_id = 1234)
當我剛剛搶學生名單中,SQL具有所有預期聯接語法有多數民衆贊成由以上版本丟失:
SELECT DISTINCT `students`.* FROM `students` INNER JOIN `registrations` ON `students`.id = `registrations`.student_id WHERE ((`registrations`.classroom_id = 9876))
爲什麼關聯擴展缺少所有的連接SQL?