ClickHouse字段分组聚合、按照任意时间段粒度查询SQL

需求

• 基础数据入库，需要根据字段做一些聚合
• 现有路口过车数据，有各种车型，需要统计总流量和各个车型流量，要一起返回
• 现有过车数据，需要按照时间不同粒度，统计车流量，实现不同时间粒度求和，5分钟、10分钟、半小时、一个月、一年都行

解决

使用if和sum

• 主要是使用if，符合条件为1，不符合为0，再使用sum求和

select
	count(1) as "总流量",
	SUM(if(vehicle_type = 'PEDESTRIAN', 1, 0)) as "行人流量",
	SUM(if(vehicle_type = 'NON_MOTORIZED', 1, 0)) as "非机动车流量",
	SUM(if(vehicle_type = 'LIGHT_DUTY', 1, 0)) as "小型车流量",
	SUM(if(vehicle_type = 'MEDIAN_SIZED', 1, 0)) as "中型车流量",
	SUM(if(vehicle_type = 'OVERSIZE', 1, 0)) as "大车流量"
from
	passing_vehicle
where
	exist_time > 0
	and time_stamp > toDateTime('2022-06-30 11:00:00')
	and time_stamp < toDateTime('2022-06-30 15:00:00')
;

使用toStartOfInterval

select
	toStartOfInterval(time_stamp , INTERVAL 30 minute) as half_hour,
	count(1) as "总流量",
	SUM(if(vehicle_type = 'PEDESTRIAN', 1, 0)) as "行人流量",
	SUM(if(vehicle_type = 'NON_MOTORIZED', 1, 0)) as "非机动车流量",
	SUM(if(vehicle_type = 'LIGHT_DUTY', 1, 0)) as "小型车流量",
	SUM(if(vehicle_type = 'MEDIAN_SIZED', 1, 0)) as "中型车流量",
	SUM(if(vehicle_type = 'OVERSIZE', 1, 0)) as "大车流量"
from
	passing_vehicle
where
	exist_time > 0
	and time_stamp > toDateTime('2022-06-30 11:00:00')
	and time_stamp < toDateTime('2022-06-30 15:00:00')
group by
	half_hour,
order by
	half_hour;