title: Convert interval to minutes
body: <p>Let's suppose I have 2 intervals:</p>
  
  <pre><code>INTERVAL '0 00:30:00' DAY TO SECOND
  INTERVAL '0 04:00:00' DAY TO SECOND
  </code></pre>
  
  <p>What is the most elegant way to get amount of minutes in each interval. <code>30</code> and <code>240</code> accordingly.</p>
  
  <p>Yes, I know I can perform <code>EXTRACT(HOUR FROM interval) * 60 + EXTRACT(MINUTE FROM interval)</code>, but this looks terrible to me.</p>
  
  <p>Any better solutions?</p>