java - hibernate 。如何为字段组合添加唯一索引？

Question

我有以下 hibernate 映射:

@Entity
public class UserPattern {
    @Id
    @GeneratedValue
    Integer id;

    @ManyToOne
    @JoinColumn(name = "user_id")
    User user;

    @ManyToOne
    @JoinColumn(name = "patern_id")
    Pattern pattern;

    ...
}

hibernate 是否允许添加唯一索引，user 和 pattern 的组合是唯一的？

Answer 1

我认为它会起作用:

@Table(name="UserPattern", 
    uniqueConstraints=
        @UniqueConstraint(columnNames={"user_id", ""})

或

@Table(name="UserPattern",  uniqueConstraints={
   @UniqueConstraint(columnNames={"user_id", "patern_id"})
})