我有以下两个模型：School和User,以及它们之间的HABTM关系,带有连接表.
在此连接表中,引用User表的外键不是user_id,而是student_id.
class School < ActiveRecord::Base has_and_belongs_to_many :students,:class_name => "User",:join_table => "schools_students",:foreign_key => "student_id" end class User < ActiveRecord::Base has_and_belongs_to_many :studying_schools,:class_name => "School",:foreign_key => "school_id" end
我想在我的用户和学校设备中创建一个学校和一个用户,但在User中定义的foreign_key似乎是个问题.
fixtures / users.yml：
user1: name: Student studying_schools: school1
fixtures / schools.yml：
school1: name: School 1 active: true students: user1
加载上面的灯具会返回ActiveRecord异常：
ActiveRecord :: StatementInvalid：MysqL :: Error：’字段列表’中的未知列’user_id’：INSERT INTO schools_students(student_id,user_id)VALUES(6562055,14302562)
我究竟做错了什么 ？
解决方法
我刚刚发现它：我在habtm定义中缺少association_foreign_key.
正确的定义方法是：
class School < ActiveRecord::Base has_and_belongs_to_many :students,:association_foreign_key => "student_id" # :foreign_key is the default school_id end class User < ActiveRecord::Base has_and_belongs_to_many :studying_schools,:foreign_key => "student_id" # :association_foreign_key is the default school_id end