设计表：一对多，一对一同时？ [英] Designing Tables: One to many and one to one at same time?

问题描述

我不确定我是否正确建模这种类型的关系，也许有人可以提供一些洞察这是否是健全的：

说我们具有典型的父子类型关系，其中每一个父母可以具有许多孩子，但是我们需要跟踪父母的单个（喘息）喜欢的孩子...

---

表父

- FavoriteChildID

---

表Child

- ParentID

所以链接交叉，其中一个是多对一，另一个是一对一。这是否被认为是好的设计？最好在子表中有一个列，在任何时候只有一行被标记为最喜欢的列？还有什么？

谢谢。

解决方案

附加表格如何？

 code>表最喜欢（
，parent_id 
，child_id 
，主键（parent_id）
）; 
  

这将有助于所有面向收藏的查询。

I'm not sure if I'm modeling this type of relationship correctly, perhaps someone could provide some insight into whether or not this is sound:

Say we have a typical parent-children type relationship where each one parent could have many children, but we need to keep track of the parent's single (gasp) favorite child...

---

Table Parent

- FavoriteChildID

and

---

Table Child

- ParentID

so the links criss-cross, where one is a many to one, and the other is one to one. is this considered good design? Would it be better to have a column in the child table where only one row could be flagged a favorite at any time? Something else?

Thanks.

解决方案

How about an additional table?

table favourite(
  ,parent_id
  ,child_id
  ,primary key(parent_id)
);

It would help if for all favourite-oriented queries.

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