JPA：@PrimaryKeyJoinColumn（...）和@JoinColumn（...，insertable =？，updatable =？）相同？ [英] JPA: is @PrimaryKeyJoinColumn(...) the same as @JoinColumn(..., insertable = ?, updatable = ?)?

问题描述

你可以从JPA规范中得出，如果 @PrimaryKeyJoinColumn（...），它没有可插入和可更新的参数，则与

Can you derive from the JPA spec, if @PrimaryKeyJoinColumn(...), which doesn't have the insertable and updatable parameters, is the same as

@JoinColumn(..., insertable = false, updatable = false)

或

@JoinColumn（...，insertable = true，updatable = true）

用于常规（非继承）关联？他们应该可以互换吗？设置的可插入和可更新属性是什么？它们是否适合任何东西？注意，我只是针对两个（似乎）实现的只读属性...

when used on regular (non-inheritance) associations? Should they be interchangable? What are the insertable and updatable properties set to? Are they set to anything at all? Note, I'm only targeting the read-only attribute that both (seem to) implement...

我与EclipseLink和Hibernate的映射异常相当不一致。 ..

I'm getting rather inconsistent mapping exception with EclipseLink and Hibernate...

这是 @PrimaryKeyJoinColumn JavaEE 5 + 6 Javadoc：

Here's the @PrimaryKeyJoinColumn JavaEE 5 + 6 Javadoc:

PrimaryKeyJoinColumn（JavaEE 5） < br>
PrimaryKeyJoinColumn（JavaEE 6）

引用：

...它可能用于OneToOne映射，其中引用实体的主键用作引用实体的外键。

... and it may be used in a OneToOne mapping in which the primary key of the referencing entity is used as a foreign key to the referenced entity.

推荐答案

是的，两者是等价的。

请注意，在JPA 2.0中，您还可以添加 @Id 到 @OneToOne 映射并完全避免重复的基本id属性。

Note in JPA 2.0 you can also add an @Id to a @OneToOne mapping and avoid having the duplicate basic id attribute altogether.

参见

• 身份和排序>通过OneToOne和ManyToOne关系的主要密钥
  和


• OneToOne>目标外键，主要键入加入列，级联主键

• Identity and Sequencing > Primary Keys through OneToOne and ManyToOne Relationships and
• OneToOne > Target Foreign Keys, Primary Key Join Columns, Cascade Primary Keys

来自 WikiBooks Java Persistence 页面

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