MyBatis以集合方式批量新增（推荐）

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" );
    }
}

2、编写UserMapper接口

@Mapper
public interface UserMapper {
 
    Integer insertUsers(List<User> userList);
}

3、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>

4、输出结果

一万条数据总耗时：521ms

MyBatis-Plus提供的InsertBatchSomeColumn方法（推荐）

1、编写EasySqlInjector 自定义类

public class EasySqlInjector extends DefaultSqlInjector {
 
 
    @Override
    public List<AbstractMethod> getMethodList(Class<?> mapperClass, TableInfo tableInfo) {
        // 注意：此SQL注入器继承了DefaultSqlInjector(默认注入器)，调用了DefaultSqlInjector的getMethodList方法，保留了mybatis-plus的自带方法
        List<AbstractMethod> methodList = super.getMethodList(mapperClass, tableInfo);
        methodList.add(new InsertBatchSomeColumn(i -> i.getFieldFill() != FieldFill.UPDATE));
        return methodList;
    }
 
}

2、定义核心配置类注入此Bean

@Configuration
public class MybatisPlusConfig {
 
    @Bean
    public EasySqlInjector sqlInjector() {
        return new EasySqlInjector();
    }
}

3、编写UserService服务类

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.insertBatchSomeColumn(userList);
        long end = System.currentTimeMillis();
        System.out.println("一万条数据总耗时：" + (end-start) + "ms" );
    }
}

4、编写EasyBaseMapper接口

public interface EasyBaseMapper<T> extends BaseMapper<T> {
    /**
     * 批量插入 仅适用于mysql
     *
     * @param entityList 实体列表
     * @return 影响行数
     */
    Integer insertBatchSomeColumn(Collection<T> entityList);
}

5、编写UserMapper接口

@Mapper
public interface UserMapper<T> extends EasyBaseMapper<User> {
    
}

6、单元测试结果

一万条数据总耗时：575ms