title: Difference between two dates sqlite
body: <p>I'm trying to calculate the difference between two dates in <code>sqlite</code>.
  My times are at the format : <code>15h30</code></p>
  
  <p>When I try this : </p>
  
  <pre><code>select time(replace( FIRSTHOUR , 'h' , ':'))-time(replace (SECONDHOUR , 'h' , ':')) 
  from table
  </code></pre>
  
  <p>I just get the result in hour like <code>2</code> if my dates are <code>15h30</code> and <code>17h40</code></p>
  
  <p>How can I get the result in hour and minute like <code>2:10</code>? </p>