这个“\u ifbk”约束在我的表中做什么?

users
id | name | email | ...

academic_records
id | scholar_id | gpa | ...

academic_records.scholar_id 是对的外键引用 users.id ,但我没有对那张桌子施加任何其他限制。错误如下所示:

Mysql::Error: Cannot add or update a child row: a foreign key constraint fails
 (`my_db`.`academic_records`, CONSTRAINT `academic_records_ibfk_1`
 FOREIGN KEY (`id`) REFERENCES `academic_records` (`id`) ON DELETE CASCADE): ...

CREATE TABLE `academic_records` (
  `gpa` varchar(10) DEFAULT NULL,
  ...
  PRIMARY KEY (`id`),
  KEY `index_academic_records_on_scholar_id` (`scholar_id`),
  CONSTRAINT `academic_records_ibfk_1` FOREIGN KEY (`id`)
    REFERENCES `academic_records` (`id`) ON DELETE CASCADE
) ENGINE=InnoDB AUTO_INCREMENT=177 DEFAULT CHARSET=utf8;

我不知道它是怎么到那里的,也不知道它是干什么的。为什么表会有一个从它自己的ID到它自己的外键?我可以取消限制吗?如果是,怎么做?我知道我为什么要从 用户id 到 学术记录.scholar\u id ,但事实上,这对我来说毫无意义。