Question

如果我有以下数据库记录

DATE        ITEMNAME

2014-02-10  A
2014-02-10  B
2014-02-10  C
2014-02-11  D
2014-02-11  E
2014-02-11  F
2014-02-11  G
2014-02-11  H
2014-02-12  I
2014-02-12  J
2014-02-12  K
2014-02-12  L
2014-02-13  M
2014-02-13  N

如何返回每天的累积库存余额，以便返回如下内容：

DATE        Total
2014-02-10  3
2014-02-11  8
2014-02-12  12
2014-02-13  14

Answer 1

这对你有用。它从您的表中获取不同的日期，然后计算每个日期之前或之前的条目数。

WITH
CTE_Dates AS (
    SELECT DISTINCT DATE
    FROM [TableName]
)
SELECT DATES.DATE,
       COUNT(*) AS Total
FROM CTE_Dates DATES
INNER JOIN [TableName] STOCKS
    ON DATES.DATE >= STOCKS.DATE
GROUP BY DATES.DATE

Answer 2

如果您有SQL 2012或SQL 2014，则可以尝试以下操作。这是SQL Fiddle。

 SELECT 
     [DATE], 
     SUM(COUNT(ITEMNAME)) OVER(ORDER BY [DATE] 
                               ROWS BETWEEN UNBOUNDED PRECEDING 
                               AND CURRENT ROW) AS StockCount
  FROM MyTable
  group by [DATE];

如何获取每一天的当前记录

2 个答案: