条件CASCADE操作的外键约束？ [英] Conditional CASCADE operation for foreign key constraint?

问题描述

我有父母和小孩表格其中小孩有一个FK指向父表的PK。当我删除父表中的某些内容时，我可以通过删除 ON DELETE CASCADE 。

I have parent and child table where child has a FK pointing to the PK of parent table. When I delete something in parent table I can have child records deleted as well by having ON DELETE CASCADE.

来删除子记录。 ，在我的父母表中我根本不删除记录。相反，我设置了列 state =passive。我想删除子表中的相关条目。

However, in my parent table I don't delete records at all. Instead I set the column state = "passive". I want to delete related entries in the child table.

我们是否有类似于conditional CASCADE Postgres的？或者是手动删除子元素表中的元素的解决方案？

Do we have something like a "conditional CASCADE" in Postgres? Or is the solution to manually delete entries in the child table?

推荐答案

你将不得不在一个触发器上执行这个操作ON UPDATE。在NEW.state =passive的地方，删除子行。

You would have to do this in a trigger that takes action ON UPDATE. Where the NEW.state = "passive", delete the child rows.

这篇关于条件CASCADE操作的外键约束？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！