has_many通過與基於關係表的條件的關係（Rails 2.3.5）

Question

我有一個如下關係。

companies_employee.rb 
belongs_to :employee 
belongs_to :company 
validates_presence_of :role 

employee.rb 
has_many :companies_employees 
has_many :companies, :through => :companies_employees 

company.rb 
has_many :companies_employees 
has_many :managers, :through => :companies_employees, :source => :employee, conditions => {:role => "Manager"} 
has_many :owners, :through => :companies_employees, :source => :employee, :conditions => {:role => "Owner"} 

我的問題是，當它檢查的條件，它試圖找到在員工表中的角色列，但角色列是companies_employees表。 有沒有辦法讓它在這個表中使用這些條件？

Answer 1

嘗試這樣：

has_many :managers, :through => :companies_employees, :source => :employee, conditions => ["employees.role = 'Manager"] 
has_many :owners, :through => :companies_employees, :source => :employee, conditions => ["employees.role = 'Owner"]