Question

我有一个简单的Customers（customerID）表和一个Orders表（orderID，orderdate）

我需要获得两周前收到订单的所有客户的清单，以及他们在该周之前所有订单的数量。

SELECT c.id_customer
FROM customer AS c
JOIN order AS o ON o.customerID = c.customerID
WHERE o.delivery_date = DATEADD(Day,-14,GETDATE())

但我不知道如何在那个周之前获得订单数量。

Answer 1

您可以使用<=获取行并使用having子句检查在给定日期是否确实存在一行：

select c.id_customer, count(*) as order_count
from customer as c
join orders as o on o.customerID = c.customerID
where o.delivery_date <= DATEADD(Day, - 14, GETDATE())
group by c.id_customer
having count(case when o.delivery_date = DATEADD(Day, -14, GETDATE()) then 1 end) > 0;

另请注意，我将表名order更改为orders，因为order是SQL保留关键字，使用关键字作为表/列标识符通常是个坏主意。

Answer 2

SELECT c.customerID,o.orderID, count(o.delivery_date)
FROM customer AS c
JOIN order AS o ON o.customerID = c.customerID
WHERE o.delivery_date = DATEADD(Day,-14,GETDATE())
group by c.customerID,o.orderID

Answer 3

尝试使用其他样本数据

 Declare @DaysAgo int=14 --para to be pass in proc
    declare @To Datetime=DATEADD(second,-1,cast((DATEADD(Day, - (@DaysAgo-1), cast(GETDATE() as date)) ) as DATETIME))
   declare @From Datetime=cast((DATEADD(Day, - @DaysAgo, cast(GETDATE() as date)) ) as DATETIME)


    select c.id_customer, count(*) as order_count
    from customer as c
    join orders as o on o.customerID = c.customerID
    where o.delivery_date >= @From AND 
    o.delivery_date <= @To
    group by c.id_customer

SQL Server：订单日期和订单之前

3 个答案: