mysql - 我想编写以下查询 Rails 方式

Question

select DISTINCT firstname 
  from users u 
    inner join  members m 
      on m.user_id = u.id 
    inner join  member_roles m1 
      on m1.member_id = m.id 
    inner join roles r
      on r.id = m1.role_id  
  where r.name  = 'Project Coordinator'

这给出了完美的结果

我尝试以上面的方式编写查询rails喜欢

s = MemberRole.joins(:role).where("roles.name" => "Project Coordinator")

@u = User.select("users.firstname").includes(:members => s )

但似乎没有任何帮助？提前致谢

Answer 1

User.select("users.firstname").includes(:members => [{:member_roles => :role}]).where("roles.name" => "Project Coordinator")