JPA：@OrderColumn和实体的可见状态？ [英] JPA: @OrderColumn and visible state of an entity?

问题描述

这是后续问题：

是JPA支持的@ManyToMany（mappedBy = ...）+ @OrderColumn？

我指的是 @OrderColumn Java文档：

http://docs.oracle.com/javaee/6/api/javax/persistence/OrderColumn.html

文本与JPA 2规范在 11.1.39 OrderColumn Annotation 中写入的内容相同。

订单栏作为实体状态的一部分不可见部分的含义是什么意思准确地？这里有很多解释的余地​​。

这是否意味着订单栏不能是定义的任何FK和/或PK的一部分？或者只有不在FK（PK允许）？一个实体的状态包含什么？ AFAIK JPA规范没有定义这个。

谢谢 解决方案

订单栏不是实体类（es）中的字段，因此它不可见（如此）。

This is a followup question to:

Is @ManyToMany(mappedBy = ... ) + @OrderColumn supported by the JPA?

I'm referring to the @OrderColumn Java docs:

http://docs.oracle.com/javaee/6/api/javax/persistence/OrderColumn.html

The text there is the same as what the JPA 2 spec writes in section 11.1.39 OrderColumn Annotation.

What does the part "the order column is not visible as part of the state of the entity" mean exactly? There's a lot of room for interpretation on that.

Does that mean the order column must not be part of any FKs and/or PKs defined? Or only not in FKs (PK allowed)? What does the state of an entity comprise? AFAIK the JPA spec doesn't define that.

Thanks

解决方案

The order column is not a field in the Entity class(es), so it isn't visible (as such).

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