<update id="updateBatchById" parameterType="java.util.List">
    update table
    <trim prefix="set" suffixOverrides=",">
      <trim prefix=" `price` = case " suffix=" end, ">
        <foreach collection="list" item="item">
          <if test="item.price != null">
            when `id` = #{item.id} then #{item.price}
          </if>
        </foreach>
      </trim>
      <trim prefix=" `update_time` = case " suffix=" end, ">
        <foreach collection="list" item="item">
          <if test="item.updateTime != null">
            when `id` = #{item.id} then #{item.updateTime}
          </if>
        </foreach>
      </trim>
    </trim>
    where id in
    <foreach collection="list" item="item" open="(" close=")" separator=",">
      #{item.id}
    </foreach>
</update>

上面就是批量更新的sql语句，修改为自己的表和字段就可以使用了！！！