How can i add a autoincrement to a column with a doctrinemigration?

I'am writing a migration in Doctrine and开发者_如何转开发 i have to add a autoincrement to a column, but i don't find any information to do so via the changeColumn-method.

$options = array('auto_increment' => true);
$this->changeColumn('table_name', 'column_name', 'integer', $options);

$options = array('auto_increment' => true);