如何在@ElementCollection上指定主键 [英] How to specify a Primary Key on @ElementCollection

问题描述

因此，如果某些表缺少主键，则innodb的行为可能会导致问题.

So, there is that behavior with innodb that can cause problem if some tables lack of primary key.

因此，对于Hibernate，我正在寻找一个键来指定@ElementCollection表上的主键，并使用Set作为基础数据结构.

So with Hibernate, I am looking for a key to specifies a primary key on a @ElementCollection table with a Set as the underling data structure.

我找到了一种在地图上拥有主键的方法，但这有点奇怪，因为我不需要地图.

I found a way to have a primary key with a map, but it is kind of weird because I do not need a map.

我也找到了与@Embeddable相关的答案，但是我不需要那种复杂性.我在实体中使用Set或Set作为数据结构.

I also found an answer related to @Embeddable, but I do not need that kind of complexities. I am using a Set or Set as the data structure in my entities.

有什么想法要实现吗?

推荐答案

如果使用Set并将元素Column设置为非null，则hibernate将使用join列和element列作为主键.

If you use a Set and make the element Column be not null, then hibernate will make a primary key with the join column and element column.

示例:

@Column(name = "STRINGS", nullable = false)
@ElementCollection
private Set<String> strings;

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