Mybatis批量操作sql写法

Mybatis批量操作sql写法

在使用foreach时,collection属性值的三种情况:

如果传入的参数类型为List时,collection的默认属性值为list,同样可以使用@Param注解自定义keyName;

  • 如果传入的参数类型为array时,collection的默认属性值为array,同样可以使用@Param注解自定义keyName;
  • 如果传入的参数类型为Map时,collection的属性值可为三种情况:

    1.遍历map.keys;
    2.遍历map.values;
    3.遍历map.entrySet()

批量Insert,参数为List<Object>

mysql的批量新增sql的写法示例,先看一下mapper的写法;

    void batchSaveUser(List<SysUser> userList);

接下来看sql如何写:

   <insert id="batchSaveUser">
       insert into sys_user (ding_user_id, username, nickname, password, email, 
       mobile, avatar, creator_id, create_time, updator_id, update_time, is_delete)
       values
       <foreach collection="list" item="user" separator=",">
           (
           #{user.dingUserId}, #{user.username}, #{user.nickname}, #{user.password}, #{user.email},
           #{user.mobile}, #{user.avatar}, #{user.creatorId}, now(), #{user.updatorId}, now(), 0
           )
       </foreach>
   </insert>

批量Insert,参数为Map<Long, List<Long>>

void batchSaveGroupAndUser(@Param("map") Map<Long, List<Long>> groupUserMap);

接下来看sql如何写:

	<insert id="batchSaveGroupAndUser" parameterType="java.util.Map">
        insert into sys_group_member (group_id, user_id, creator_id, create_time)
        values
        <foreach collection="map.keys" item="groupId" separator=",">
            <foreach collection="map[groupId]" item="userId" separator=",">
                (
                #{groupId}, #{userId}, 'admin', now()
                )
            </foreach>
        </foreach>
    </insert>

批量Insert,参数为Map<String, String>

	void batchInsert(@Param("map") Map<String, String> map);
	<insert id="batchInsert" parameterType="java.util.Map">
        insert into brand_info (code, `name`, is_delete, create_time)
        values
        <foreach collection="map.entrySet()" index="key" item="value" open="(" close=")" separator=",">
            #{key}, #{value}, 0, now()
        </foreach>
    </insert>

如果是只需要遍历key,写法则是collection=“map.keys”

	<insert id="batchSave" parameterType="java.util.Map">
        insert into brand_info (code, is_delete, create_time)
        values
        <foreach collection="map.keys" item="key" open="(" close=")" separator=",">
            #{key}, 0, now()
        </foreach>
    </insert>

同理,如果是只需要遍历value,写法则是collection=“map.values”

	<insert id="batchSave" parameterType="java.util.Map">
        insert into brand_info (code, is_delete, create_time)
        values
        <foreach collection="map.values" item="value" open="(" close=")" separator=",">
            #{value}, 0, now()
        </foreach>
    </insert>

批量Update,参数为List<Object>

**注意:**在执行批量Update的时候,数据库的url配置需要添加一项参数:&allowMultiQueries=true

如果没有这个配置参数的话,执行下面的更新语句会报错:在这里插入图片描述

正确的sql写法如下:

	<update id="batchUpdateCorporation" parameterType="java.util.List">
        <foreach collection="list" item="item" index="index" separator=";">
            update sys_corporation set
            <if test="item.name != null and item.name !=''">
                `name` = #{item.name},
            </if>
            <if test="item.code != null and item.code !=''">
                code = #{item.code},
            </if>
            <if test="item.parentCode != null and item.parentCode !=''">
                parent_code = #{item.parentCode},
            </if>
            updater = 'system',
            update_time = now()
            where id = #{item.id}
        </foreach>
    </update>