title: What should I do to make a Polymorphic Relationships in RoR?
body: <p>I have a user table, and have a role column, that identify their role. Now, I want to add a "Student" table, that have the student's student number, and I also want to add a "Teacher", to store the teacher's salary. </p>
  
  <p>Both the Student and Teacher are the subclass of User. Now, I added a role column already in the User table, "T" = Teacher, and "S" = Student. Now, I want to add "Student" and "Teacher" in  the database. What should I do? Generate scaffold  or migration only? Also, it is necessary to modify my models? or I just need to modify the controller only??</p>
  
  <p>Thank you.</p>