oracle - Hibernate + oracle 序列 + 触发器

Question

我有一个由使用序列的触发器自动填充索引的表(Oracle 数据库)

CREATE TABLE A
(
  IDS                           NUMBER(10)      NOT NULL
)


CREATE OR REPLACE TRIGGER A_TRG
BEFORE INSERT
ON A REFERENCING NEW AS New OLD AS Old
FOR EACH ROW
BEGIN
  :new.IDS := A_SEQ.nextval;
END A_TRG;
/

我有一个匹配的 Java 类:

Class A {
   @Id
   @SequenceGenerator(name = "aSequence", sequenceName = "A_SEQ", allocationSize = 1)
   @GeneratedValue(generator = "aSequence", strategy = GenerationType.SEQUENCE)
   @Column(name = "IDS")
   Long id;

   ...
}

当我尝试像这样持久化 A 的实例时:

EntityTransaction transaction = entityManager.getTransaction();
transaction.begin();
A a = new A();
Long id = getHibernateTemplate().save(a);
transaction.commit();

我得到这个问题:

保存调用返回的代码中的 ID = “X”

数据库中的 ID = “X+1”

有没有办法设置 Hibernate 让数据库触发器创建 ID？

谢谢

Answer 1

回复发现于 HIbernate issue with Oracle Trigger for generating id from a sequence

我需要调整我的触发器以仅在没有给出 ID 的情况下运行:

CREATE OR REPLACE TRIGGER A_TRG
BEFORE INSERT
ON A REFERENCING NEW AS New OLD AS Old
FOR EACH ROW
WHEN (New.IDS is null) -- (1)
BEGIN
  :new.IDS := A_SEQ.nextval;
END A_TRG;
/

(1) 这一行允许 Hibernate 手动调用 A_SEQ.nextVal 来设置 ID，然后绕过触发器，否则 Hibernate 将无用地获取 nextval，因为触发器总是会再次调用 nextval 重置 ID