PermissionModel::undefine PHP 메소드

    public function undefine($Names)
    {
        $Names = (array) $Names;
        $St = $this->Database->Structure();
        $St->table('Permission');
        foreach ($Names as $Name) {
            if ($St->columnExists($Name)) {
                $St->DropColumn($Name);
            }
        }
        $St->reset();
    }