title: MySQL `timestamp` to be updated even with same column value
body: <p>I am using timestamp columns to one of my table, and using the auto update functionality. Here is my table schema:</p>
  
  <pre><code>mysql&gt; desc user_rides;
  +------------+--------------+------+-----+-------------------+-----------------------------+
  | Field      | Type         | Null | Key | Default           | Extra                       |
  +------------+--------------+------+-----+-------------------+-----------------------------+
  | id         | int(11)      | NO   | PRI | NULL              | auto_increment              |
  | user_id    | int(11)      | NO   | MUL | NULL              |                             
  | ride_cnt   | int(11)      | YES  |     | NULL              |                             |
  | created_at | timestamp    | NO   |     | CURRENT_TIMESTAMP |                             |
  | updated_at | timestamp    | NO   |     | CURRENT_TIMESTAMP | on update CURRENT_TIMESTAMP |
  +------------+--------------+------+-----+-------------------+-----------------------------+
  5 rows in set (0.02 sec)
  </code></pre>
  
  <p>What I'm expecting is that, </p>
  
  <blockquote>
    <ul>
    <li><code>created_at</code> column to be initialize with the time, the row gets created and</li>
    <li><code>updated_at</code> column to be same as <code>created_at</code> and also updated when any of the columns(basically <code>ride_cnt</code>) get updated.</li>
    </ul>
  </blockquote>
  
  <p>This works great.<br><br>
  But what I am also expecting is that the <code>updated_at</code> to be updated even if <code>ride_cnt</code> has the same value. So that I can keep a track of when was the last time the row's value fetched and can be ignored for further run.</p>
  
  <p>For example:</p>
  
  <p>The rows with <code>ride_cnt</code> = 0 to be updated with the latest time we ran the update. So that the rows can be ignored for quite sometime to be reinitialize.</p>
  
  <p>Is there any way we can achieve this without passing in timestamp manually?</p>
  
  <p>Edit:</p>
  
  <p>Here what's happening,</p>
  
  <pre><code>mysql&gt; insert into user_ride set user_id=7445, user_ride=0;
  Query OK, 1 row affected (0.01 sec)
  
  mysql&gt; insert into user_ride set user_id=7009, user_ride=2;
  Query OK, 1 row affected (0.00 sec)
  
  mysql&gt; select * from user_ride;
  +----+---------+-----------+---------------------+---------------------+
  | id | user_id | user_ride | created_at          | updated_at          |
  +----+---------+-----------+---------------------+---------------------+
  |  1 |    7445 |         0 | 2017-06-13 10:44:05 | 2017-06-13 10:44:05 |
  |  2 |    7009 |         2 | 2017-06-13 10:44:18 | 2017-06-13 10:44:18 |
  +----+---------+-----------+---------------------+---------------------+
  2 rows in set (0.00 sec)
  
  mysql&gt; update user_ride set user_ride=0 where id=1;
  Query OK, 0 rows affected (0.01 sec)
  Rows matched: 1  Changed: 0  Warnings: 0
  
  mysql&gt; select * from user_ride;
  +----+---------+-----------+---------------------+---------------------+
  | id | user_id | user_ride | created_at          | updated_at          |
  +----+---------+-----------+---------------------+---------------------+
  |  1 |    7445 |         0 | 2017-06-13 10:44:05 | 2017-06-13 10:44:05 |
  |  2 |    7009 |         2 | 2017-06-13 10:44:18 | 2017-06-13 10:44:18 |
  +----+---------+-----------+---------------------+---------------------+
  2 rows in set (0.00 sec)
  
  mysql&gt; update user_ride set user_ride=1 where id=1;
  Query OK, 1 row affected (0.01 sec)
  Rows matched: 1  Changed: 1  Warnings: 0
  
  mysql&gt; select * from user_ride;
  +----+---------+-----------+---------------------+---------------------+
  | id | user_id | user_ride | created_at          | updated_at          |
  +----+---------+-----------+---------------------+---------------------+
  |  1 |    7445 |         1 | 2017-06-13 10:44:05 | 2017-06-13 10:45:26 |
  |  2 |    7009 |         2 | 2017-06-13 10:44:18 | 2017-06-13 10:44:18 |
  +----+---------+-----------+---------------------+---------------------+
  2 rows in set (0.00 sec)
  </code></pre>