title: Perform queries/tasks on specific users
body: <p>I got a user system, with session for both their username and ID. I also got a field in my users table named <code>user_locked</code> which determines if the user's account is locked or not (if it's locked; they can't log in).</p>
  
  <p>Recently I added a feature on my site where it allows me to lock users easily by one click, and I then got the idea: <strong>is it possible to force that specific user to get logged out (make his/her session/cookies get destroyed) while leaving everyone elses unharmed?</strong></p>
  
  <p>Is it possible? If it is, how would I do?</p>
  
  <p>Thanks.</p>