Question

我正在尝试计算在2009年6月1日之前90天和2009年6月1日之后90天销售的商品，并在下面进行查询。它显示了一些错误。请有人亲切地为我做好准备吗???

SELECT
location,                       
SUM((CASE WHEN t.order_date DATEADD (DAY, -90, '6/1/2009') THEN t.Item ELSE NULL END) as Prior_Items,
SUM(CASE WHEN t.order_date DATEADD (DAY, 89,  '6/1/2009') THEN t.Item ELSE NULL END) as Post_Items
ELSE NULL
END)
FROM mytable t
where date = '6/1/2009'
group by location

Answer 1

你的WHEN条件没有正确形成。

CASE WHEN t.order_date DATEADD (DAY, -90, '6/1/2009') THEN t.Item ELSE NULL END
          ^^^^^^^^^^^^^^^^^^^^

很可能你想要的东西是：

CASE WHEN t.order_date>=DATEADD (DAY, -90, '6/1/2009') THEN t.Item ELSE NULL END
                      ^^

Answer 2

我认为你想要这样的东西。

DECLARE @d DATETIME

SET @d = '20090106'


SELECT
location,                       
SUM(CASE WHEN t.order_date < @d and  t.order_date > DATEADD (DAY, -90, @d) THEN t.Item END) as Prior_Items,
SUM(CASE WHEN t.order_date >=@d AND  t.order_date <  DATEADD (DAY, 89,   @d) THEN t.Item END) as Post_Items
FROM mytable t
where t.order_date BETWEEN  DATEADD (DAY, -90, @d) AND DATEADD (DAY, 89,   @d)
group by location

计算日期范围

2 个答案: