计算连续 30 天数据的平均值

Question

我正在寻找可以提供过去 30 天和持续到最后 30 天数据的查询。

例如 - 如果今天是 6/30 den，我应该能够在 5/30 和 4/30 之前提取数据。我已经尝试了下面的代码，但它只提供了过去 30 天的数据

SELECT Avg(Sub.Ticket) AS Average2
FROM (SELECT Fulldate, COUNT(Ticket_Number) AS Ticket
      FROM RawData
      GROUP BY Fulldate
     )  AS sub
WHERE ((([RawData].[FullDate])>=#6/30/2016#-30-30));

Answer 1

如果你想要 1 行 2 列的结果：

SELECT 
  AVG(sub.TicketLast30) AS AverageLast30,
  AVG(sub.TicketPrev30) AS AveragePrev30
FROM (
  SELECT Fulldate, 
    COUNT(IIF(Fulldate BETWEEN (DATE()-30) AND DATE(), Ticket_Number, 0) AS TicketLast30,
    COUNT(IIF(Fulldate BETWEEN (DATE()-60) AND (DATE()-30), Ticket_Number, 0) AS TicketPrev30
  FROM RawData
  WHERE Fulldate BETWEEN (DATE()-60) AND DATE()
  GROUP BY Fulldate
) AS sub

如果您希望结果为 2 行 1 列：

SELECT 
  AVG(sub.Ticket) AS Average30
FROM (
  SELECT Fulldate, 
    COUNT(Ticket_Number) AS Ticket
  FROM RawData
  WHERE Fulldate BETWEEN (DATE()-60) AND (DATE()-30)
  GROUP BY Fulldate
) AS sub
UNION ALL
SELECT 
  AVG(sub.Ticket) AS Average30
FROM (
  SELECT Fulldate, 
    COUNT(Ticket_Number) AS Ticket
  FROM RawData
  WHERE Fulldate BETWEEN (DATE()-30) AND DATE()
  GROUP BY Fulldate
 ) AS sub