title: Four (4) Sub Queries
body: <p>Is there any possible way to do this kind of sub query:</p>
  
  <pre><code>DELETE (INSERT (SELECT (INSERT)))
  </code></pre>
  
  <p>I know how to: <code>INSERT (SELECT)</code>:</p>
  
  <pre><code>INSERT INTO r (u_id,role) 
      VALUES ((SELECT u_id FROM USER WHERE email="mumair1992@gmail.com"),'Agent');
  </code></pre>
  
  <p>My problem is:<br>
  User is present in request table when he verifies his account, system must have to:</p>
  
  <ol>
  <li>Create user in user table  </li>
  <li>Create user role in role table  </li>
  <li>Delete user from request table</li>
  </ol>