Question

我有一个表（SQL Server 2017），其中的数据按年和周的级别存储。

    +---------+-------------+---------+----------+-----+
    | year_id | week_number | good_id | store_id | qty |
    +---------+-------------+---------+----------+-----+
    | 2019    | 42          | 113466  | 41       | 7   |
    +---------+-------------+---------+----------+-----+

我需要得到一个类似的表，但是在日级别，每天的数量（数量）将平均分为7个部分。

+---------+-------------+---------+----------+-----+------------+
| year_id | week_number | good_id | store_id | qty | date_id    |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-14 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-15 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-16 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-17 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-18 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-19 |
+---------+-------------+---------+----------+-----+------------+
| 2019    | 42          | 113466  | 41       | 1   | 2019-10-20 |
+---------+-------------+---------+----------+-----+------------+

我找到了进入get a date from the year and week number的方法，但是如何一次获得7行呢？

Answer 1

您可以创建一个日历表，如图here所示并按如下所示连接原始表以获得所需的输出。

Select 
      CalendarDate
      , year_id
      , week_number
      , good_id
      , store_id
      , 1 as qty
from dbo.RunningNumbers
inner join ToBeGenerated on CalendarYear = year_id and week_number = CalendarWeek

这是现场db<>fiddle演示。

Answer 2

你去了。您需要将具有所有日期的表联接起来，然后将数量除以所需的值：


use tempdb

CREATE TABLE tbl1
(
   year_id INT, week_number INT, good_id INT, store_id INT, qty INT
)

INSERT INTO tbl1
VALUES (2019, 42, 113466, 41, 7)
GO
WITH sample AS(
   SELECT CAST('2019-10-01' AS DATE) as DT
   UNION ALL
   SELECT DATEADD(dd,1,dt)
    FROM sample
   WHERE DATEADD(dd,1,dt) < CAST('2019-12-31' AS DATE))

SELECT dt, YEAR(dt) AS [Year], DATEPART(WEEK,dt) AS Week
INTO wks
FROM sample

SELECT t.year_id, t.week_number, t.good_id, t.store_id, qty/7 AS [Qty], dt AS [Date]
  FROM tbl1 t
 INNER JOIN wks S on s.Week = t.week_number

从年和周的组合中提取一周中的7天作为日期？

2 个答案: