设置无数据时traffic的数据为0

src/main/java/com/nis/web/dao/dashboard/NtcTotalReportDao.xml

@@ -32,7 +32,7 @@
   </select>
   <!-- 根据最近时间条获取带宽，进出口流量 -->
 	<select id="getNetFlowPortInfoNew" resultType="java.util.HashMap">
-		SELECT SUM(total_traffic.inoctets) AS inoctets , SUM(total_traffic.outoctets) AS outoctets FROM (
+		SELECT  COALESCE(SUM(total_traffic.inoctets),0) AS inoctets ,  COALESCE(SUM(total_traffic.outoctets),0) AS outoctets FROM (
 			SELECT sum(case direction when 1 then c2s_byte_len+s2c_byte_len else 0 end)  inoctets ,sum(case direction when 0 then c2s_byte_len+s2c_byte_len else 0 end) outoctets FROM traffic_trans_statistic
 			where stat_time =  (SELECT stat_time FROM traffic_trans_statistic WHERE entrance_id=1 and stat_time > DATE_SUB(now(), INTERVAL 15 MINUTE)  ORDER BY stat_time DESC LIMIT 0,1) and entrance_id=1
 			UNION ALL