JPA：外键注解 [英] JPA: foreign key annotation
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问题描述
我有两个数据库实体：论坛和主题。
I've got two database entities: Forum and Topic.
主题的保护长forumId 数据成员，这表明当然的主题的论坛。
Topic has protected long forumId data member, which indicates of course the Topic's forum.
我的问题是用什么注解这个数据成员？
My question is what annotation to use for this data member?
推荐答案
作为论坛有很多话题和主题属于独一无二的论坛，你可能想要去与<一个注解一个论坛类型属性href=\"http://docs.oracle.com/javaee/6/api/javax/persistence/ManyToOne.html\"><$c$c>@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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