Question

根据包含CustomerID，Date和Daily Sales字段的表，我需要计算每个CustomerID，Date组合的前7天销售额。样本数据如下：

CustomerID  Date    Daily Sales
    1   10/18/16    $100
    1   10/17/16    $50
    1   9/1/16  $20
    1   8/5/16  $20
    1   7/1/16  $20
    1   6/15/16 $20
    1   1/1/16  $20
    2   10/18/16    $50
    2   10/17/16    $50
    2   10/16/16    $50
    2   10/15/16    $50
    2   10/14/16    $50

所需的输出如下：

CustomerID  Date    Daily Sales Last 7 Days Sales
1   10/18/16    $100    $150
1   10/17/16    $50 $50
1   9/1/16  $20 $20
1   8/5/16  $20 $20
1   7/1/16  $20 $20
1   6/15/16 $20 $20
1   1/1/16  $20 $20
2   10/18/16    $50 $250
2   10/17/16    $50 $200
2   10/16/16    $50 $150
2   10/15/16    $50 $100
2   10/14/16    $50 $50

以下是我正在使用的查询：

SELECT
t1.[CustomerID]
,CAST(t1.[Date] AS DATE) AS Date
,SUM(t1.[DailySales]) AS [DailySales]
,SUM(t2.[DailySales]) AS [Last7DaysSales]
FROM TABLE_NAME t1 LEFT OUTER JOIN TABLE_NAME t2 ON t1.[CustomerID] = t2.[CustomerID]
AND CAST(t2.[Date] AS DATE) BETWEEN DATEADD(DAY, -7, t1.[Date]) and t1.[Date]

GROUP BY t1.[CustomerID], CAST(t1.[Date] AS DATE)
ORDER BY t1.[CustomerID], CAST(t1.[Date] AS DATE) DESC;

为Last7DaysSales按预期返回值，但仅对当天的销售不正确。我确定我正在做一些愚蠢的事情导致这个问题......

Answer 1

SELECT SUM(Column) FROM TABLE_NAME WHERE date < (GETDATE()-7) AND CustomerId=1 - 为您提供客户ID = 1的每日销售额。

Answer 2

您可以构造基本查询以获取除Last7DaysSales值之外的所有内容，然后使用子查询计算它：

SELECT
t1.[CustomerID]
,CAST(t1.[Date] AS DATE) AS Date
,SUM(t1.[DailySales]) AS [DailySales]
,(select sum(t2.[DailySales]) 
  from TABLE_NAME t2 
  where t1.CustomerID = t2.CustomerID
  and cast(t2.[Date] as date) between dateadd(day, -7, cast(t1.[Date] as date)) and cast(t1.[Date] as date)
 ) as [Last7DaysSales]
FROM TABLE_NAME t1 LEFT OUTER JOIN TABLE_NAME t2 ON t1.[CustomerID] = t2.[CustomerID]
AND CAST(t2.[Date] AS DATE) BETWEEN DATEADD(DAY, -7, t1.[Date]) and t1.[Date]
GROUP BY t1.[CustomerID], CAST(t1.[Date] AS DATE)
ORDER BY t1.[CustomerID], CAST(t1.[Date] AS DATE) DESC;

请注意，窗口函数是一种更有效的方法，但这种方法可能更直观一些。

SQL - 前七天销售（每位客户，每个日期）

2 个答案: