title: Set INTERVAL as variable in mysql ADDDATE
body: <p>I have this line in mysql:</p>
  
  <pre><code>SELECT &lt;columns&gt;
  FROM table
  WHERE TIME_TO_SEC(TIMEDIFF(NOW(), ADDDATE(DATE_OF_REG, INTERVAL 1 HOUR))) / 3600 &gt;= 24
  </code></pre>
  
  <p>I also have a TIMEZONE column which stores the time difference from the server as a number.
  How can I add this number somehow in the ADDDATE function?
  E.g. ADDDATE(DATE_OF_REG, INTERVAL, TIMEZONE) or something...</p>