title: How to update only the hour from a DATETIME field in MySQL?
body: <p>I want to update a DateTime column where it will change the hours only without modifying anything else. I can't use to add an interval as the values all are different. There is many different dates too. So need to change the hour of exact desired date as where condition. </p>
  
  <p>Ex:</p>
  
  <pre><code>*************************************************
  **        Before       *|*         After       **
  ************************|************************
  ** 2017-07-24 19:06:15 *|* 2017-07-24 15:06:15 **
  ** 2017-07-24 17:12:23 *|* 2017-07-24 15:12:23 **
  ** 2017-07-24 23:00:03 *|* 2017-07-24 15:00:03 **
  ** 2017-07-24 20:33:56 *|* 2017-07-24 15:33:56 **
  ** 2017-07-24 18:19:31 *|* 2017-07-24 15:19:31 **
  ** 2017-07-24 16:43:47 *|* 2017-07-24 15:43:47 **
  *************************************************
  </code></pre>
  
  <p>Want to do it with MySQL query only without using any programming language. </p>