修改无人机平均值，最小值和最大值直接从list集合中取

ZhuDongming

2019-08-19 b2ea3adf3787f53487ad10faa116df0d586de652

 src/main/resources/mapper/DeviceMapper.xml

@@ -414,4 +414,8 @@
         </if>
      )
   </select>
	
   <select id="getLimitDataByDevice" resultType="String">
      SELECT limit_val FROM view_device_density WHERE mac = #{mac}
   </select>
</mapper>