在 Phalcon 中扩展模型

如何在Phalcon MVC模型之间建立子父关系？

这是我想到的数据库模式：

explain show;
+---------+--------------+------+-----+---------+-------+
| Field   | Type         | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| id      | int(11)      | NO   | PRI | NULL    |       |
| length  | int(11)      | NO   |     | NULL    |       |
| title   | varchar(100) | NO   |     | NULL    |       |
+---------+--------------+------+-----+---------+-------+
explain show_episode;
+---------+--------------+------+-----+---------+-------+
| Field   | Type         | Null | Key | Default | Extra |
+---------+--------------+------+-----+---------+-------+
| show_id | int(11)      | NO   | PRI | NULL    |       |
| season  | int(11)      | NO   |     | NULL    |       |
| episode | int(11)      | NO   |     | NULL    |       |
+---------+--------------+------+-----+---------+-------+

show_episode中的每个元素也存在于show表中，但是有些显示记录仅存在于show中。

这个想法是有两个Phalcon模型类：

class Show extends Phalcon'Mvc'Model
{
  public $id;
  public $length;
  public $title;
}
class ShowEpisode extends Show 
{
  public $season;
  public $episode;
}

我需要如何配置这些模型才能像这样检索和保存剧集记录：

// retrieve
$episode = ShowEpisode::findFirst(array("id"=>333));
echo $episode->season;
echo $episode->title;
// save
$episode->title = "New Title";
$episode->season = 3;
$episode->save();