title: mysql convert_tz not working in where clause
body: <p>I have a <code>datetime</code> field and am trying to use <code>CONVERT_TZ</code> to look <code>BETWEEN</code> dates.  Here's an example just selecting:</p>
  
  <pre><code>SELECT (DATE_FORMAT(CONVERT_TZ(`created_at`,'+00:00','+05:00'), ' %Y-%m-%d')) FROM `pages`
  </code></pre>
  
  <p>This works fine and returns results.  However, when I try to use this in a <code>WHERE</code> clause that should return results:</p>
  
  <pre><code>SELECT 
      *
  FROM
      `pages`
  WHERE
      (DATE_FORMAT(CONVERT_TZ(`created_at`, '+00:00', '+05:00'),
              '%Y-%m-%d')) BETWEEN '2017-05-01' AND '2017-05-30'
  </code></pre>
  
  <p>This doesn't return anything.    But those between dates, there are many many records that should validate between those. </p>