Hibernate+Postgresql: PK not starting from 1 (PG sequence created from 1 starting)

Question

我有一个 table，主键是 SERIAL 类型。此主键受如下序列影响：

CREATE SEQUENCE swq
INCREMENT 1 MINVALUE 1 MAXVALUE 9223372036854775807
START 1 CACHE 1;

我的问题是：为什么主键在第一次执行 saveorUpdate() 方法后创建了第一条记录，但将 id 字段插入为零 (0) 而不是一个 (1)？

来自 OP 的评论：

@Entity @Table(name = "table", schema = "schem") 
public class tableBE implements java.io.Serializable 
{ 
  private int idmotiv; 

  @Id @Column(name = "_id", unique = true, nullable = false) 
  public int getIdmot() { return this.idmot; }
}

Answer 1

使用@GeneratedValue 和@SequenceGenerator 注解配置。下面是例子。

@Id
@GeneratedValue(generator="Hib_Seq")
@SequenceGenerator(name="Hib_Seq", sequenceName="swq")
private int idmotiv;

Hibernate+Postgresql: PK not starting from 1 (PG sequence created from 1 starting)

Hibernate+Postgresql: PK not starting from 1 (PG sequence created starting from 1)

database

postgresql

hibernate

sequence