title: Mysql modify UNSIGNED attribute to specific column
body: <p>I have a issue adding <code>unsigned</code> attribute to existing column. </p>
  
  <pre><code>SET FOREIGN_KEY_CHECKS=0;
  ALTER TABLE cla_budget MODIFY COLUMN id UNSIGNED;
  SET FOREIGN_KEY_CHECKS=1;
  </code></pre>
  
  <p><strong>Error:</strong> <em>#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'UNSIGNED' at line 1.</em></p>
  
  <p>I´ve tried sql modify command alone, result is same error as above:</p>
  
  <pre><code>ALTER TABLE cla_budget MODIFY COLUMN id UNSIGNED;
  </code></pre>
  
  <p>Also tried: </p>
  
  <pre><code>1. ALTER TABLE `cla_budget` MODIFY COLUMN `id` UNSIGNED;
  2. ALTER TABLE `cla_budget` MODIFY COLUMN `id` unsigned;
  3. ALTER TABLE `cla_budget` MODIFY `id` unsigned;
  ...
  </code></pre>
  
  <p>I searched for sollution here, also in mysql manual. I ran queries in <strong>phpMyAdmin</strong>.</p>
  
  <p><strong>Database server:</strong></p>
  
  <ul>
  <li><p>Server version: 5.7.15-9-log - Percona Server (GPL), Release '9', Revision '9f0fd0a'</p></li>
  <li><p>Protocol version: 10</p></li>
  <li><p>Mysql 5.7</p></li>
  </ul>
  
  <p>What am I missing? Thanks.</p>