首先,對於提供燃料的變化爲每輛車每一天的查詢,你可以使用下面的SQL:
SELECT trip_range.dt
, trip_range.vehicle_id
, st.fuel_content as start_fuel_content
, en.fuel_content as end_fuel_content
, en.fuel_content - st.fuel_content as fuel_change
FROM (
SELECT tp.vehicle_id, DATE(tp.creation_time) dt
, MIN(tp.creation_time) start_time
, MAX(tp.creation_time) end_time
FROM trip_parameters tp
GROUP BY tp.vehicle_id, DATE(tp.creation_time)
) as trip_range
JOIN trip_parameters st
ON st.vehicle_id = trip_range.vehicle_id
AND st.creation_time = trip_range.start_time
JOIN trip_parameters en
ON en.vehicle_id = trip_range.vehicle_id
AND en.creation_time = trip_range.end_time
WHERE trip_range.dt BETWEEN '2012-11-08' AND '2012-11-09'
如果你想在燃料在所有的車輛每天的累計變動額在範圍內,以下SQL應該工作:
SELECT dt, SUM(fuel_change) as fuel_change
FROM (
SELECT trip_range.dt
, en.fuel_content - st.fuel_content as fuel_change
FROM (
SELECT tp.vehicle_id, DATE(tp.creation_time) dt
, MIN(tp.creation_time) start_time
, MAX(tp.creation_time) end_time
FROM trip_parameters tp
GROUP BY tp.vehicle_id, DATE(tp.creation_time)
) as trip_range
JOIN trip_parameters st
ON st.vehicle_id = trip_range.vehicle_id
AND st.creation_time = trip_range.start_time
JOIN trip_parameters en
ON en.vehicle_id = trip_range.vehicle_id
AND en.creation_time = trip_range.end_time
WHERE trip_range.dt BETWEEN '2012-11-08' AND '2012-11-09'
) change_by_vehicle
GROUP BY 1
希望這有助於!
約翰。
舉個例子一些數據,它 –
請嘗試自己的東西,並告訴我們當前的代碼,電流輸出和您的預期輸出..這將幫助我們找到解決方案 – Konza