Hibernate继承，在两个不同的表中重复ID

Question

@Entity
@Table(name = "parent");
@Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
    public class Parent {

    @Id
    @SequenceGenerator(name = "ME_SEQ", sequenceName = "ME_SEQ", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "ME_SEQ")
    @Column(name = "PARENT_ID", columnDefinition = "NUMBER(38,0)", nullable = false, unique = true)
    private Long id;
}

还有一个子实体（单独的表），它具有指向父ID的PK和FK 。

@Entity
@Table(name = "child")
public class Child extends Parent {

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

即使有两个分开的表，我也会从Hibernate中得到一个错误：

  

org.hibernate.mapping.UnionSubclass无法转换为   org.hibernate.mapping.RootClass

即使子类与父类的表不同，子类中是否也没有ID？