title: Asp.net database migration, what's the Down method for?
body: <p>When I add-migration, Up and Down method are generated.</p>
  
  <p>and I know when I update database (update-database), it runs the Up method.</p>
  
  <p>How about Down method? </p>
  
  <p>when it will run, is it for rollback? and, how can I run it?</p>