Mybatis批量操作sql写法

Bertha 。 2024-04-18 15:44 86阅读 0赞

### Mybatis批量操作sql写法 ###

*   *  foreach时，collection属性值的三种情况：
     *  批量Insert，参数为List

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## 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);

<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][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p4MTEwNTAz_size_16_color_FFFFFF_t_70]

<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>

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p4MTEwNTAz_size_16_color_FFFFFF_t_70]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/18/9213a474ebb2410c92de35dcf3ac6450.png