Question

假设我有一个包含以下列的表：

数量，INTEGER
SaleDate，DATETIME

我现在想看到这个结果：

Sold in the last 7 days | Sold in last 14 days
-----------------------------------------------------
10                      | 20

我可以使用where子句在之间使用，但是如何在7天和14天内获得售出的数量？

Answer 1

在WHERE子句中过滤以获取第0天到第14天。然后分别在第0天到第7天汇总。

SELECT
   ...,
   SUM(CASE WHEN SaleDate >= DATEADD(day, -7, GETDATE()) THEN 1 ELSE 0 END) AS 7days,
   COUNT(*) AS 14days
FROM
   MyTable
WHERE
   SaleDate >= DATEADD(day, -14, GETDATE())
GROUP BY
   ...

Answer 2

select sum(Qty), datediff(w, getdate(), SaleDate) as Period
from table
group by  datediff(ww, getdate(), SaleDate)

Answer 3

在MS T-SQL 2003中测试

declare @whatever table(
    qty int,
    saledate datetime
)
insert into @whatever select 1, getdate()
insert into @whatever select 2, dateadd(dd, -1, getdate())
insert into @whatever select 2, dateadd(dd, -2, getdate())
insert into @whatever select 1, dateadd(dd, -3, getdate())
insert into @whatever select 1, dateadd(dd, -4, getdate())
insert into @whatever select 1, dateadd(dd, -5, getdate())
insert into @whatever select 1, dateadd(dd, -6, getdate())
insert into @whatever select 1, dateadd(dd, -7, getdate())
insert into @whatever select 1, dateadd(dd, -8, getdate())
insert into @whatever select 1, dateadd(dd, -9, getdate())
insert into @whatever select 2, dateadd(dd, -10, getdate())
insert into @whatever select 2, dateadd(dd, -11, getdate())

insert into @whatever select 1, dateadd(dd, -15, getdate())
insert into @whatever select 2, dateadd(dd, -16, getdate())

select
        qty,
        sum(
            case
                when datediff(dd, saledate, getdate()) between 0 and 7 then 1
                else 0
            end
        ) as [Sold in last 7 days],
        sum(
            case
                when datediff(dd, saledate, getdate()) between 0 and 14 then 1
                else 0
            end
        ) as [Sold in last 14 days]
    from
        @whatever
    group by
        qty
;

如何使用SQL来执行具有不同日期的组？

3 个答案: