• 描述不同触发器类型的区别• 描述数据库触发器和它们的用途• 创建数据库触发器• 描述数据库触发器的点火(firing ) 规则• 删除触发器-•　Describe the difference between different types of triggers •　describe the use of database triggers and their triggers •　•　describe the database to create the database trigger ignition (firing) rules •　Delete trigger