title: How to determine if an employee is a manager?
body: <p>Using the table EMP, where MANAGER represents the employee's manager:</p>
  
  <pre><code>EMPLOYEE   MANAGER
  1          NULL
  2          1
  3          1
  4          2
  5          2
  </code></pre>
  
  <p>How can I make a query that determines if an employee is a manager?</p>
  
  <pre><code>EMPLOYEE   STATUS
  1          IS MANAGER
  2          IS MANAGER
  3          IS NOT MANAGER
  4          IS NOT MANAGER
  5          IS NOT MANAGER
  </code></pre>
  
  <p>Is it possible to do this without a subquery?</p>