我需要帮助每个月计算所采取的电流值一米基础的消费使用滞后()来进行计算
我有以下表格:
地址(邮编INT,街VARCHAR)
仪表(MeterID INT,InstallationDate日期,邮编INT)
阅读(ReadNo INT,ReadDate日期,ReadValue INT,MeterID INT,ReaderID INT)
我试过如下:
Select ReadDate,
ReadValue AS CurrentValue,
lag(readvalue, 1, 0) OVER (ORDER BY READVALUE) AS PreviousValue,
readvalue - lag(readvalue, 1, 0) OVER (ORDER BY READVALUE) AS Consumption
From Reading R,
Meter M,
Address A
Where R.MeterID = M.MeterID
AND A.PostCode = M.PostCode AND A.PostCode = '1005'
Order By ReadDate;
问题发生时,该地址的仪表是由一个新的仪表替换,谁能帮助我吗?
嗨吉姆,介意为我审查ERD?我怀疑它是否能起到作用。非常感谢你的帮助。 – FirstTimer