MyBatis中批量插入和批量更新的实现方法详解

create table user (
	id bigint auto_increment comment '记录唯一ID',
	user_code varchar(50) COLLATE utf8mb4_unicode_ci default '' not null comment '用户编码',
	user_name varchar(50) COLLATE utf8mb4_unicode_ci default '' not null comment '用户姓名',
	age int(12) default 18 null comment '年龄',
	salary int(12) default 0 null comment '工资',
	email varchar(100) default '' null comment '邮箱',
	primary key (id),
	unique key 'uk_user_code' (user_code)
) ENGINE=InnoDB auto_increment=1 CHARSET=utf8 COMMENT='用户信息表';

public class User {
	private Long id;
	private String userCode;
	private String userName;
	private Integer age;
	private String email;
	private Integer salary;
	//...getter/setter省略...
}

insert into user (user_code, user_name, age)
values 
('zhangsan','张三',18),('lisi','李四',20),
('wangwu','王五',30),('laoliu','老六',36)

update user set 
	email = 
	case
		when user_code = 'zhangsan' then 'zhangsan01@163.com'
		when user_code = 'lisi' then 'lisi03@163.com'
		when user_code = 'wangwu' then 'wangwu06@163.com'
	end,
	salary = 
	case
		when age < 21 and user_name like '李%' then salary+200
		when age > 21 and user_name like '王%' then salary+400
	end
where user_code in ('zhangsan','lisi','wangwu')

@Mapper
public interface UserMapper {
	/**批量插入用户数据*/
	int batchInsertUser(@Param("userList") List<User> userList)
	/**批量更新用户数据*/
	int batchUpdateUser(@Param("userList") List<User> userList)
}

<!-- 其它省略 -->
<!-- 批量插入数据 -->
<insert id="batchInsertUser" parameterType="java.util.List">
	insert into user (user_code, user_name, age)
	values 
	<foreach collection="userList" item="user" index="index" separator=",">
		(#{user.userCode},
		#{user.userName},
		#{user.age})
	</foreach>
</insert>
<!-- 批量更新数据 -->
<update id="batchUpdateUser">
	upate user 
	<trim prefix="set" suffixOverrides=",">
		<trim prefix="email = case" suffix="end,">
			<foreach collection="userList" item="user" index="index">
				when user_code = #{user.userCode} then #{user.email}
			</foreach>
		</trim>
		<trim prefix="salary = case" suffix="end,">
			<![CDATA[ when age < 21 and user_name like '李%' then salary+200 ]]>
			<![CDATA[ when age > 21 and user_name like '王%' then salary+400 ]]>
		</trim>	
	</trim>
	where user_code in (
		<foreach collection="userList" item="user" index="index" separator=",">
			#{user.userCode}
		</foreach>
	)
</update>

public interface UserServicve {
	/**批量数据插入*/
	int batchInsertUser(List<User> userList);
	/**批量数据更新*/
	int batchUpdateUser(List<User> userList);
}

public class UserServicveImpl implements UserServicve {
	@Autowired
	private UserMapper userMapper;
	/**批量数据插入*/
	@Overwrite
	public int batchInsertUser(List<User> userList) {
		if (CollectionUtil.isEmpty(userList)) {
			return 0;
		}
		return userMapper.batchInsertUser(userList);
	}
	/**批量数据插入*/
	@Overwrite
	public int batchUpdateUser(List<User> userList) {
		if (CollectionUtil.isEmpty(userList)) {
			return 0;
		}
		return userMapper.batchUpdateUser(userList);
	}
}