详解MySQL如何实现数据批量更新

UPDATE t_sys_user SET `desc` = 'CaseWhen-0' WHERE id IN (1001,1002,1003);

<update id="updateForeach">

    <foreach collection="list" item="param" separator=";">

        UPDATE t_sys_user

        <set>

            <if test=" param.desc != null and param.desc != ''">

                `desc` = #{param.desc}

            </if>

        </set>

        WHERE id = #{param.id}

    </foreach>

</update>

<update id="updateBatchCaseWhen">

    UPDATE t_sys_user

    <set>

        <trim prefix="`DESC`= CASE id" suffix="END,">

            <foreach collection="list" item="param">

                <if test="param.id != null">

                    WHEN #{param.id} THEN #{param.desc}

                </if>

            </foreach>

        </trim>

<!--            <trim prefix="username = CASE id" suffix="END,">

            <foreach collection="list" item="param">

                <if test="param.username != null and param.username != ''">

                    WHEN #{param.} THEN #{param.username}

                </if>

            </foreach>

        </trim>  

-->

    </set>

    <where>

        id in

        <foreach collection="list" item="param" separator="," open="(" close=")">

            #{param.id}

        </foreach>

    </where>

</update>