public static function find_last($class_name, $options = array())
{
if ($options['order']) {
$options['order'] = SqlBuilder::reverse_sql_order($options['order']);
} else {
$options['order'] = '`' . self::get_table_name($class_name) . '`.`' . call_user_func(array($class_name, 'primary_key')) . '` DESC';
}
return self::find_first($class_name, $options);
}