example migration

m121114_001614_printmethod.php

<?php
class m121114_001614_printmethod extends DbMigration
{
    public function up()
    {
	$this->qs("ALTER TABLE `print_method` ADD COLUMN `default_printer_id`  int(11) NOT NULL AFTER `printer_type`");
        Yii::app()->cache->flush();
    }
}