java - 如何连接同一张表中的多列？

Question

我有 2 个表“student”和“picklist”。
选择列表 - 使用它 作为州、国家、城市等列表的通用表。

这里是学生类:

@Entity
public class Student {
    @Id
    Long id;
    String firstName;
    String lastName;
    Long accountId;

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumns({@JoinColumn(name="country",referencedColumnName = "name"),
        @JoinColumn(name="accountId",referencedColumnName = "accountId")}
    )
    PickList country;

    @OneToOne(fetch=FetchType.EAGER)
    @JoinColumns({@JoinColumn(name="state",referencedColumnName = "name"),
        @JoinColumn(name="accountId",referencedColumnName = "accountId")}
    )
    PickList state;
}

这是选择列表:

@Entity
@Table(name = "picklist", uniqueConstraints = {
    @UniqueConstraint(columnNames = {"accountId", "name"})
})
public class PickList {
    @Id
    long id;

    long accountId;
    String name;
}

错误—— Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: column: accountid (should be mapped with insert="false"update="false")

Answer 1

信息很明确:您在映射中有一个重复的列。这意味着您将同一个数据库列映射了两次。

尝试这样做 @JoinColumn(name="accountId",referencedColumnName = "accountId", 可插入=假，可更新=假)