怎么使用SQL实现车流量的计算(SQL,开发技术)

卡口转换率

将数据导入hive，通过SparkSql编写sql,实现不同业务的数据计算实现，主要讲述车辆卡口转换率，卡口转化率：主要计算不同卡口下车辆之间的流向，求出之间的转换率。

1、查出每个地区下每个路段下的车流量

select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycarORDERby action_time)asn1FROM traffic.hive_flow_action

此结果做为表1，方便后面错位连接使用

2、通过错位连接获取每辆车的行车记录

通过表1的结果，与自身进行错位链接，并以车牌为分区，拼接经过卡口的过程

(select t1.car, t1.monitor_id, concat(t1.monitor_id, "->", t2.monitor_id)aswayfrom ( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t1leftjoin( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t2on t1.car=t2.car andt1.n1=t2.n1-1where t2.action_timeisnotnull)

获取到每辆车的一个行车记录，经过的卡口

3、获取行车过程中的车辆数

获取卡口1~卡口2，…等的车辆数有哪些,即拿上面的行车记录字段进行分区在进行统计

(select s1.way, COUNT(1)sumCarfrom --行车过程(select t1.car, t1.monitor_id, concat(t1.monitor_id, "->", t2.monitor_id)asway from ( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t1 leftjoin( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t2on t1.car=t2.car andt1.n1=t2.n1-1 where t2.action_timeisnotnull)s1groupbyway)

4、获取每个卡口的总车辆数

获取每个卡口最初的车辆数，方便后面拿行车轨迹车辆数/总车辆数，得出卡口之间的转换率

select monitor_id, COUNT(1)sumallfrom traffic.hive_flow_actiongroupby monitor_id

5、求出卡口之间的转换率

select s2.way, s2.sumCar/s3.sumallzhlfrom ( select s1.way, COUNT(1)sumCar from --行车过程( select t1.car, t1.monitor_id, concat(t1.monitor_id, "->", t2.monitor_id)asway from ( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t1 leftjoin( select car, monitor_id, action_time, ROW_NUMBER()OVER(PARTITIONbycar ORDERby action_time)asn1 FROM traffic.hive_flow_action)t2on t1.car=t2.car andt1.n1=t2.n1-1 where t2.action_timeisnotnull)s1 groupby way)s2leftjoin --每个卡口总车数( select monitor_id, COUNT(1)sumall from traffic.hive_flow_action groupby monitor_id)s3on split(s2.way, "->")[0]=s3.monitor_id