JPA:外键注释 [英] JPA: foreign key annotation
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问题描述
我有两个数据库实体:Forum 和 Topic.
I've got two database entities: Forum and Topic.
Topic 有protected long forumId 数据成员，当然表示Topic 的论坛.
Topic has protected long forumId data member, which indicates of course the Topic's forum.
我的问题是该数据成员使用什么注释?
My question is what annotation to use for this data member?
推荐答案
由于论坛有很多主题，并且一个主题属于一个且唯一的论坛，您可能希望使用带有 @ManyToOne:
As Forum has many topics, and a topic belongs to one and only Forum, you probably want to go with a Forum type attribute annotated with @ManyToOne:
@ManyToOne
@JoinColumn(name = "forumId")
private Forum forum;
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