java - 是否可以指示hibernate在执行插入时不要设置空值？

Question

我有实体:

@Entity
@Table(name = "message")
public class Message {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "id")
    private Integer id;

    @Column(name = "email")
    private String email;

    @Column(name = "subject")
    private String subject;

    @Column(name = "content")
    private String content;

    @Column(name = "html")
    private String html;

    @Column(name = "status")
    private Integer status;

    @Column(name = "creation_date")
    private Date creationDate;

    @Column(name = "send_date")
    private Date sendDate;

    //GET, SET
}

表 message 对列 creation_date 的定义如下:

creation_date timestamp without time zone NOT NULL DEFAULT now()\

作为结论，当我没有为 creation_date 设置特定值时，hibernate 将生成如下所示的查询:

insert into partner.message (content, creation_date, email, html, send_date, status, subject) 
values ('text', null, 'text', 'text', null, '1', 'text')

是否有可能避免生成那些 null 值？

顺便说一句，我正在使用 PostgreSQL。它与 PostgreSQL-dialect 有关系吗？

Answer 1

您应该将列 creationDate 设置为不可空:

@Column(name = "creation_date", nullable = false)
private Date creationDate;

IIRC，如果插入为空，Hibernate 应该抛出异常。这样您就必须确保它始终处于设置状态。

另一种选择是为创建日期设置默认值:

@Column(name = "creation_date", nullable = false)
private Date creationDate = new Date(); //Or set it in the constructor