title: Adding time to mysql timestamp column, with condition
body: <p>I have 3 time-related columns in my table: </p>
  
  <pre><code>vreme_od (TIME), vreme_do(TIME), datum(CURRENT TIMESTAMP)
  </code></pre>
  
  <p><code>vreme_od</code> and <code>vreme_do</code> have <code>H:i:s</code> time values (the difference between <code>vreme_od</code> and <code>vreme_do</code> is 1 hour), <code>vreme_do</code> can be update from a script. </p>
  
  <p>The thing is, I have to come up with a catch that updates <code>vreme_do</code> till a certain time, let's say, 21:00. </p>
  
  <p>So, If you fire up the script at 20:53, for an example, <code>vreme_od</code> will have a value of "20:53:00", and <code>vreme_do</code> should have a value of "07:53:00" on the next day. </p>
  
  <p>Can some one help me with this, I'm stuck for days with it...</p>