title: Dynamically populate dropdown list without reloading page
body: <p>I've a table named <code>course</code>. 
  which contains fields</p>
  
  <pre><code>COURSEID, COURSENAME
  </code></pre>
  
  <p>Another Table named <code>STUDENTS</code>. which contains </p>
  
  <pre><code>STCODE, STNAME, COURSEID
  </code></pre>
  
  <p>I've a preloaded Dropdown List of Courses. I'd like to populate the second Dropdown List with the students who are in the selected <code>course</code> from the first dropdown list without reloading the page.</p>