MybatisPlus物理删除、逻辑删除
- 物理删除：数据在物理层面删除了，文件中没有这条数据了
- 逻辑删除：修改了标记，文件中还是存在的
基于这几篇博客修改
物理删除
package com.xiang;
import com.baomidou.mybatisplus.annotation.TableField;
import com.xiang.mapper.UserMapper;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
/**
* Created by IntelliJ IDEA.
* User: xiang
* Date: 2021/10/23 1:44
*/
@SpringBootTest
public class PhysicalDeletion {
@Autowired
UserMapper userMapper;
/**
* 实现物理删除
*/
@Test
//通过id删除
void deleteById() {
int deleteById = userMapper.deleteById(1451572730934198273l);
if (deleteById > 0) {
System.out.println("删除成功");
} else {
System.out.println("删除失败");
}
}
@Test
//批量删除
void deleteBatchIds() {
int batchIds = userMapper.deleteBatchIds(Arrays.asList(603, 604));
if (batchIds > 0) {
System.out.println("删除成功");
} else {
System.out.println("删除失败");
}
}
@Test
//条件删除 条件与删除
void deleteByMap() {
HashMap<String, Object> map = new HashMap<>();
map.put("username", "向向");
map.put("age", 18);
int byMap = userMapper.deleteByMap(map);
if (byMap > 0) {
System.out.println("删除成功");
} else {
System.out.println("删除失败");
}
}
}
通过id删除
JDBC Connection [HikariProxyConnection@643552582 wrapping com.mysql.cj.jdbc.ConnectionImpl@1937eaff] will not be managed by Spring
==> Preparing: DELETE FROM user WHERE id=?
==> Parameters: 1451572730934198273(Long)
<== Updates: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@c2584d3]
删除成功
批量删除
JDBC Connection [HikariProxyConnection@2038185019 wrapping com.mysql.cj.jdbc.ConnectionImpl@4012d5bc] will not be managed by Spring
==> Preparing: DELETE FROM user WHERE id IN ( ? , ? )
==> Parameters: 603(Integer), 604(Integer)
<== Updates: 2
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@1caa9eb6]
删除成功
条件删除
JDBC Connection [HikariProxyConnection@1464031233 wrapping com.mysql.cj.jdbc.ConnectionImpl@2da66a44] will not be managed by Spring
==> Preparing: DELETE FROM user WHERE age = ? AND username = ?
==> Parameters: 18(Integer), 向向(String)
<== Updates: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@2e869098]
删除成功
删除前
删除后
逻辑删除
数据库中添加deleted字段
千万不要用delete关键字、不然你懂的...
user类中添加deleted属性
添加@TableLogic注解
package com.xiang.pojo;
import com.baomidou.mybatisplus.annotation.*;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.Date;
/**
* Created by IntelliJ IDEA.
* User: xiang
* Date: 2021/10/21 2:50
*/
/**
* `id` int NOT NULL AUTO_INCREMENT,
* `username` varchar(12) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
* `sex` varchar(2) CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci NULL DEFAULT NULL,
* `age` int NULL DEFAULT NULL,
* `birthday` date NULL DEFAULT NULL,
*/
@Data
@AllArgsConstructor
@NoArgsConstructor
public class User {
// @TableId(type = IdType.ID_WORKER) //数字类型的id使用，当类型为Long时默认使用，生成19位的Id值，
// @TableId(type = IdType.ID_WORKER_STR)//字符串类型的id使用，需要写明注解，生成19位的Id值
//同时需要设置数据库的字段id的类型为Bigint，因为int的长度只有11位
private Long id;
private String username;
private String sex;
private int age;
private Date birthday;
/***
* 使用mybatisPlus自动填充时间
*
* 第一：添加注解
* 第二：实现MetaObjectHandler接口
* 第三：重写inserFill和updateFill方法
* 第四：调用setFieldValByName方法
*/
@TableField(fill = FieldFill.INSERT)//进行添加操作时有值
private Date createTime;
@TableField(fill = FieldFill.INSERT_UPDATE)////进行添加和修改操作时有值
private Date updateTime;
/**
* 添加version属性，注意添加@Version注解
* 同时使用TableField设置初始值为1
*/
@TableField(fill = FieldFill.INSERT)
@Version
private int version;
//添加删除标记
@TableLogic
@TableField(fill = FieldFill.INSERT)//设置初始值
private int deleted;
}
设置逻辑删除的初始值的方式有两种
1、使用TableField注解
2、在数据库给字段设置默认初始值
注：使用TableField注解和在数据库设置初始值只能选择一种，不能同时存在
测试类
package com.xiang;
import com.xiang.mapper.UserMapper;
import com.xiang.pojo.User;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import java.util.List;
/**
* Created by IntelliJ IDEA.
* User: xiang
* Date: 2021/10/23 19:22
*/
@SpringBootTest
public class LogicalDeletion {
@Autowired
UserMapper userMapper;
/**
* 实现逻辑删除
*/
@Test
void insert() {
User user = new User();
user.setUsername("小不点儿");
user.setAge(19);
int insert = userMapper.insert(user);
if (insert > 0) {
System.out.println("添加成功");
} else {
System.out.println("添加失败");
}
List<User> list = userMapper.selectList(null);
for (User listUser : list) {
System.out.println(listUser);
}
}
@Test
//根据id删除
void deleteById() {
int deleteById = userMapper.deleteById(1451895657063972866l);
if (deleteById > 0) {
System.out.println("删除成功");
} else {
System.out.println("删除失败");
}
List<User> list = userMapper.selectList(null);
for (User user : list) {
System.out.println(user);
}
}
}
删除前
删除后
JDBC Connection [HikariProxyConnection@423095039 wrapping com.mysql.cj.jdbc.ConnectionImpl@7e0bc8a3] will not be managed by Spring
==> Preparing: UPDATE user SET deleted=1 WHERE id=? AND deleted=0
==> Parameters: 1451895657063972866(Long)
<== Updates: 1
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@6fa0450e]
删除成功
JDBC Connection [HikariProxyConnection@172711139 wrapping com.mysql.cj.jdbc.ConnectionImpl@5793b87] will not be managed by Spring
==> Preparing: SELECT id,username,sex,age,birthday,create_time,update_time,version,deleted FROM user WHERE deleted=0
==> Parameters:
<== Columns: id, username, sex, age, birthday, create_time, update_time, version, deleted
<== Row: 1, xiang, 男, 18, 2021-10-03, null, null, null, 0
<== Row: 559, 小向, 男, 18, 2021-10-04, null, null, null, 0
<== Row: 602, admin, 女, 18, 2021-10-20, null, null, null, 0
<== Row: 605, 小二, 女, 18, null, null, null, null, 0
<== Row: 607, 小四, 女, 21, null, null, null, null, 0
<== Row: 609, 小五, 女, 0, null, null, null, null, 0
<== Row: 1451097869404868609, 向某, 男, 0, null, null, null, null, 0
<== Row: 1451098975287668738, 周某, 男, 0, null, null, null, null, 0
<== Total: 8
Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@178f268a]
User(id=1, username=xiang, sex=男, age=18, birthday=Sun Oct 03 00:00:00 CST 2021, createTime=null, updateTime=null, version=0, deleted=0)
User(id=559, username=小向, sex=男, age=18, birthday=Mon Oct 04 00:00:00 CST 2021, createTime=null, updateTime=null, version=0, deleted=0)
User(id=602, username=admin, sex=女, age=18, birthday=Wed Oct 20 00:00:00 CST 2021, createTime=null, updateTime=null, version=0, deleted=0)
User(id=605, username=小二, sex=女, age=18, birthday=null, createTime=null, updateTime=null, version=0, deleted=0)
User(id=607, username=小四, sex=女, age=21, birthday=null, createTime=null, updateTime=null, version=0, deleted=0)
User(id=609, username=小五, sex=女, age=0, birthday=null, createTime=null, updateTime=null, version=0, deleted=0)
User(id=1451097869404868609, username=向某, sex=男, age=0, birthday=null, createTime=null, updateTime=null, version=0, deleted=0)
User(id=1451098975287668738, username=周某, sex=男, age=0, birthday=null, createTime=null, updateTime=null, version=0, deleted=0)