Question

我需要在Department和Person之间创建一对多的hibernate关系（一个部门有很多人）。

问题在于我想保持时间有效性。如果没有ORM（休眠），很容易在指定日期选择特定部门的人员：

select * from Person where department_id = ? and ? between validFrom and validTill

如何使用JPA hibernate实现？

class Department {
  Long id;
  String code; 
  String name;
  @OneToMany(fetch = FetchType.LAZY, mappedBy = "departmentId")
  @OnDelete(action = OnDeleteAction.CASCADE)
  private Set<Person> persons = new HashSet<Person>();
}

class Person {
  Long id;
  String name;
  String surname;
  Date validFrom;
  Date validTill;
}

如果部门时间有效，如何做到这一点？

select P.* from Person P, Deparment d 
where d.code = ? and 
p.department_id = d.department_id and 
? between d.validFrom and d.validTill and 
? between p.validFrom and p.validTill

所有具有相同deparment.code的记录都是一个部门。

Answer 1

您在JPA中执行此操作的方式与使用SQL执行此操作相同。只需将其作为JPQL查询而不是SQL查询：

select p from Person p
inner join p.department d
where d.code = :departmentCode
and :today between d.validFrom and d.validTill 
and :today between p.validFrom and p.validTill

JPA（休眠）关系OneToMany与日期

1 个答案: