参考：
https://blog.csdn.net/qq_45525848/article/details/137725872
前提：使用for循环+insert单条插入1W条用时26348ms
四、MyBatis以集合方式批量新增
1、编写UserService服务类
@Service
public class UserService {
@Resource
private UserMapper userMapper;
public void InsertUsers(){
long start = System.currentTimeMillis();
List<User> userList = new ArrayList<>();
User user;
for(int i = 0 ;i < 10000; i++) {
user = new User();
user.setUsername("name" + i);
user.setPassword("password" + i);
userList.add(user);
}
userMapper.insertUsers(userList);
long end = System.currentTimeMillis();
System.out.println("一万条数据总耗时：" + (end-start) + "ms" );
}
}
3、编写UserMapper接口
@Mapper
public interface UserMapper {
Integer insertUsers(List<User> userList);
}
4、编写UserMapper.xml文件
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.ithuang.demo.mapper.UserMapper">
<insert id="insertUsers">
INSERT INTO user (username, password)
VALUES
<foreach collection ="userList" item="user" separator =",">
(#{user.username}, #{user.password})
</foreach>
</insert>
</mapper>
以下完整且规范的写法，注：如果需要MySQL支持批量操作需要在yml的url配置中新增allowMultiQueries=true，支持以;分隔批量执行SQL。
例如：
spring:
datasource:
url: jdbc:mysql://localhost:3306/test?allowMultiQueries=true&useSSL=false
username:
password:
完整代码：
<insert id="insertUserBatch">
<foreach collection ="list" item="item" separator =";">
INSERT INTO user
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="item.id != null and item.id != ''">id,</if>
<if test="item.username != null and item.username != ''">username,</if>
<if test="item.password != null and item.password != ''">password,</if>
<if test="item.sex != null and item.sex != ''">sex,</if>
<if test="item.age != null">age,</if>
<if test="item.address != null and item.address != ''">address,</if>
<if test="item.createTime != null">create_time,</if>
</trim>
VALUES
<trim prefix="(" suffix=")" suffixOverrides=",">
<if test="item.id != null and item.id != ''">#{item.id},</if>
<if test="item.username != null and item.username != ''">#{item.username},</if>
<if test="item.password != null and item.password != ''">#{item.password},</if>
<if test="item.sex != null and item.sex != ''">#{item.sex},</if>
<if test="item.age != null">#{item.age},</if>
<if test="item.address != null and item.address != ''">#{item.address},</if>
<if test="item.createTime != null">#{item.createTime},</if>
</trim>
</foreach>
</insert>
5、输出结果
一万条数据总耗时：521ms