jpa hibernate@oneToone@JoinColumn referencedColumnName被忽略

Question

在对一个与另一个有一对一关系的实体执行jpql查询时，我遇到了一个意外的行为。关键的一点是，关系是从根实体的主键到目标实体的一个字段，而目标实体不是ID。

// root entity
@Entity
@Table(name = "PERSON")

public class Person {

    @Id
    @Column(name = "PERSON_ID")
    private long id;

    private String name;

    @OneToOne(optional = false)
    @JoinColumn(name = "PERSON_ID", referencedColumnName = "PERSON_ID", insertable = false, updatable = false, unique = true)
    private Address mainAddress;
    ...
}
// referenced entity
@Entity
@Table(name = "ADDRESS")
public class Address {

    @Id
    @Column(name = "ADDRESS_ID")
    private long id;

    @Column(name = "PERSON_ID")
    private long personId;
    ...
}

select p from Person p left join fetch p.mainAddress

SELECT ... FROM PERSON p LEFT OUTER JOIN ADDRESS a ON p.PERSON_ID = a.ADDRESS_ID

SELECT ... FROM PERSON p LEFT OUTER JOIN ADDRESS a ON p.PERSON_ID = a.PERSON_ID

Answer 1

如果按原样映射@onetoone，外键将位于Person表中，即。Person表（如果您没有在@JoinColumn注释中指定person_id)应该有一个FK列'address_id'。

按照您希望生成的SQL的样子，您似乎希望FK在address表中，即address有一个FK列Person_ID。您可以通过以下方法来完成：

@Entity
@Table(name = "PERSON")

public class Person {

    @Id
    @Column(name = "PERSON_ID")
    private long id;

    private String name;

    @OneToOne(mappedBy = "person")
    private Address mainAddress;

}


@Entity
@Table(name = "ADDRESS")
public class Address {

    @Id
    @Column(name = "ADDRESS_ID")
    private long id;

    @OneToOne(optional = false)
    @JoinColumn(name = "PERSON_ID", insertable = false, updatable = false, unique = true)
    private Person person;

}