TSQL:按周对客户订单进行分组

Question

我有一张包含订单集合的表格.这些领域是:

• customerName (文本)
• DateOfOrder (约会时间).

我想显示每位客户每周的订单总数.我想安排在每周的星期五这样看起来像这样:

all dates follow mm/dd/yyyy

"bobs pizza", 3/5/2010, 10
"the phone co",3/5/2010,5
"bobs pizza", 3/12/2010, 3
"the phone co",3/12/2010,11

有人可以告诉我该怎么做？

谢谢

Answer 1

创建一个可以更容易分组的字段.

SELECT COUNT(OrderID), WeekStart
FROM 
(
 SELECT *, 
  dateadd(week, datediff(day,'20000107',yourDate) / 7, '20000107') AS WeekStart  
 FROM Orders
) o
GROUP BY WeekStart;

20000107是一个众所周知的星期五.