java - Hibernate:在 HQL 中使用共享主键

Question

当我使用实体映射共享主键时，我遇到了 Hibernate 创建的 sql 问题。我正在使用 JPA 2.1 和 Hibernate 5.2.2

这是我的实体:

@Entity
@Column(name = "employee_table")
public class EmployeeEntity {

    @Id
    @Column(name = "id")
    @SequenceGenerator
    @GeneratedValue
    private Long id;

    @OneToOne(fetch = FetchType.LAZY)
    @PrimaryKeyJoinColumn
    private EmployeeDetailsEntity employeeDetailsEntity;
}

@Entity
@Table(name = "employee_details")
public class EmployeeDetailsEntity {

    @Id
    @Column(name = "id")
    private Long id;

    // additional attributes

}

我想选择所有有详细信息的员工:

select e from EmployeeEntity e where e.employeeDetailsEntity is not null;

Hibernate 生成的选择是:

select employeeen0_.id from employee_table employeeen0_ where employeeen0_.id is not null;

您能解释一下我做错了什么并帮助解决这个问题吗？

Answer 1

看起来您缺少 Employee -> EmployeeDetails 关系映射的“另一面”:

员工实体:

private EmployeeDetails employeeDetails;

    @OneToOne(mappedBy = "employee", fetch = FetchType.LAZY)
    public EmployeeDetails getEmployeeDetails() {
        return employeeDetails;
    }

EmployeeDetails 实体:

private Employee employee;

    @OneToOne(optional = false)
    @JoinColumn(name = "EMPLOYEE_ID")
    public Employee getEmployee() {
        return employee;
    }