title: How to carry out a functionality change in the application without code changes and only database changes?
body: <p>I have been asked in an interview about this question of how to carry out a functionality change in the application without code changes and only database changes? For example</p>
  
  <p>The application is a student course registration where the condition is that the system administrator provides capability of applying to only a single course out of different courses.</p>
  
  <p>The application system should be supportable to the system administrator such that in the future the student can apply for multiple courses. </p>
  
  <p>The application should be flexible to the admin to directly change at the DB end without affecting the functionality and how to do it. </p>
  
  <p>I scratched my head but I did not got conclusion as I don't have deep knowledge about the DB.  </p>