休眠查询得到child

Question

我想获取所有 child 用户。我有两列 parent 和 child

在parenttable--

id  pname  pid(fk of parent)

1   A
2   B      1
3   C      2

在childtable---

id  cname  cid(fk of child)  pid(fk of parent)

1    AA                       1
2    BA     1                 2
3    BC     2                 2
4    CA     3                 3
5    CC     4                 3

如果parent一个-- 获取全部 child

if parent B-- 获得 BA、BB、CA、CC

if parent C-- 获取 CA,CC

我得到了答案，但它不是单一查询.. 任何休眠单一查询都可以做到这一点

更新......

public class Parent implements PersistEntity{

    @Id
    @Column(name = "parent_id")
    @SequenceGenerator(name="OH",sequenceName="OH", allocationSize=1)
    @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="OH")
    private Long parentid;

    @Column(name = "parent_name")
    private String parentName;

    @ManyToOne
    @JoinColumn(name = "fk_parent_id")
    private Parent  fkparentId;
}

public class Child implements PersistEntity{

    @Id
    @Column(name = "child_id")
    @SequenceGenerator(name="OP",sequenceName="OP",allocationSize=1)
    @GeneratedValue(strategy=GenerationType.SEQUENCE, generator="OP")
    private Long childId;

    @Column(name = "child_name")
    private String childName;

    @ManyToOne
    @JoinColumn(name = "fk_child_id")
    private Child fkchildId;

    @ManyToOne
    @JoinColumn(name = "fk_office_hierarchy_parent")
    private Parent fkparentId;
}

Answer 1

我在 jpa 中使用递归查询解决了

休眠查询得到child

Hibernate query to get child

hibernate

criteria

spring-boot