Question

我必须在Postgresql中的表中添加列 position 。我希望列自动增加。我创建序列并将列添加到表中：

CREATE SEQUENCE position_sequence START 1 MINVALUE 1 MAXVALUE 2147483647;
ALTER TABLE stage
ADD COLUMN position integer default nextval('position_sequence');

比起我在我的对象类中添加了适当的字段。 POJO看起来像这样：

@Entity
@Table(name = "stg")
public class Stg {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
    @SequenceGenerator(name = "sequenceGenerator")
    private Long id;

    @NotNull
    @Size(max = 20)
    @Column(name = "name", length = 20, nullable = false)
    private String name;

    @Column(name = "from_date")
    private ZonedDateTime fromDate;

    @Column(name = "to_date")
    private ZonedDateTime toDate;

    @SequenceGenerator(name = "position_sequence", sequenceName = "position_sequence",allocationSize = 1)
@GeneratedValue(strategy=GenerationType.SEQUENCE,generator="position_sequence") 
    private Integer position;

它与 id 一起正常工作，但是当我创建新对象 Stg 时，会将空值放在位置中，而不是使用顺序。

控制台输出

Hibernate: insert into stg (name, position, id) values (?, ?, ?)

Hibernate将空值而不是posrgresql的使用序列

0 个答案: