一、创建数据库标准
1.表的必备三个字段：id、gmt_create、gmt_modified
2.gmt_create是创建时间，gmt_modified是更新时间
3.然而创建时间和更新时间的默认设置不要让数据库来设置、统一用Mybatis-plus的Handler管理
二、数据库表结构
CREATE TABLE `ums_member` ( `id` bigint(20) NOT NULL, `username` varchar(64) DEFAULT NULL, `password` varchar(64) DEFAULT NULL, `icon` varchar(500) DEFAULT NULL, `email` varchar(100) DEFAULT NULL, `nick_name` varchar(200) DEFAULT NULL, `note` varchar(500) DEFAULT NULL, `gmt_create` datetime DEFAULT NULL, `gmt_modified` datetime DEFAULT NULL, `login_time` datetime DEFAULT NULL, `status` int(255) DEFAULT NULL, PRIMARY KEY (`id`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8;
三、使用步骤
1.实体类
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@Data
@AllArgsConstructor
@NoArgsConstructor
@TableName(value = "ums_member")
public class UmsMember implements Serializable {
@TableId(value = "id", type = IdType.NONE)
private Long id;
@TableField(value = "username")
private String username;
@TableField(value = "password")
private String password;
@TableField(value = "icon")
private String icon;
@TableField(value = "email")
private String email;
@TableField(value = "nick_name")
private String nickName;
@TableField(value = "note")
private String note;
@TableField(value = "gmt_create",fill = FieldFill.INSERT)
private Date gmt_create;
@TableField(value = "gmt_modified",fill = FieldFill.INSERT_UPDATE)
private Date gmt_modified;
@TableField(value = "login_time")
private Date loginTime;
@TableField(value = "status")
private Integer status;
private static final long serialVersionUID = 1L;
}
2.实体类操作数据库时间工具类
/**
* @author ：Mr.ZJW
* @date ：Created 2022/3/2 10:08
* @description：数据库自动插入时间工具类
*/
@Component
public class MyHandler implements MetaObjectHandler {
public void insertFill(MetaObject metaObject) {
System.out.println("添加插入时间");
this.setFieldValByName("gmt_create",new Date(),metaObject);
this.setFieldValByName("gmt_modified",new Date(),metaObject);
}
public void updateFill(MetaObject metaObject) {
System.out.println("更新插入时间");
this.setFieldValByName("gmt_modified",new Date(),metaObject);
}
}
3.测试
@SpringBootTest
@RunWith(SpringRunner.class)
public class UmsMeberTest {
@Autowired
private UmsMemberMapper umsMemberMapper;
@Test
public void test01(){
UmsMember umsMember = new UmsMember();
umsMember.setUsername("jowell");
umsMember.setStatus(0);
umsMember.setPassword("jowell");
umsMember.setNote("not");
umsMember.setNickName("cike");
umsMember.setEmail("2280252534@qq.com");
umsMemberMapper.insert(umsMember);
}操作成功:
