一个表中同一列上的两个外键 [英] Two foreign keys on the same column from one table

问题描述

我有一个项目表，其中有一个image_id字段和一个newsimage_id字段.

i have a project table which has a image_id field and a newsimage_id field.

两者都链接到图像表.但是InnoDB不允许我为 两个字段都放在同一列(id).

Both are linked to the image table. But InnoDB doesn't allow me to set a foreign key for both fields to the same column (id).

有没有办法可以做到这一点? 我正在通过MAMP使用MySQL.

Is there a way I can do this or is it not possible? I'm using MySQL through MAMP.

提前谢谢！

推荐答案

这是我的操作方式(MySQL 5.0.45):

Here's how I did it (MySQL 5.0.45):

ALTER TABLE `job_dependency`
ADD FOREIGN KEY (`job`) REFERENCES `job` (`id`),
ADD FOREIGN KEY (`dependency`) REFERENCES `job` (`id`);

在这种情况下，ON DELETE CASCADE存在问题，请不要使用它.

There are problems with ON DELETE CASCADE in this situation, so don't use it.

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