title: ERROR 1025 (HY000): Error on MODIFY column command
body: <p>I need to modify my primary key column. I want to change int to bigint. but there is an error. How can I change it? I don't want to delete keys..</p>
  
  <pre><code>ALTER TABLE items MODIFY COLUMN itemnumber bigint(12) unsigned NOT NULL AUTO_INCREMENT;
  </code></pre>
  
  <blockquote>
    <p>ERROR 1025 (HY000): Error on rename of './kohadata/#sql-3ae3_5cf5' to
    './kohadata/items' (errno: 150)</p>
  </blockquote>
  
  <p>My table;</p>
  
  <pre><code> CREATE TABLE `items` (
    `itemnumber` int(11) NOT NULL AUTO_INCREMENT,
    `biblionumber` int(11) NOT NULL DEFAULT '0',
  
      PRIMARY KEY (`itemnumber`),
  ) ENGINE=InnoDB AUTO_INCREMENT=2147483647 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci
  </code></pre>