Question

我需要获取一年中一周的开始日期和结束日期。

这是我的输入内容

YEAR = 2019 WEEK = 32

结果将是：05/08/2019和11/08/2019。

我尝试过：

select (dateadd(week,32-(1),dateadd(week,datediff(week,(-1),dateadd(year,datediff(year,(0),getdate()),(0))),(0))))
select (dateadd(week,32+datediff(week,(0),dateadd(year,datediff(year,(0),getdate()),(0))),(-1)))

但没有年份输入，因此仅适用于当前年份我需要将此函数放入计算字段中，以创建表

Answer 1

一个可能的选择是以下语句：

DECLARE @year int = 2019
DECLARE @week int = 32
DECLARE @date date

SELECT @date = DATEADD(week, (@week - 1), DATEFROMPARTS(@year, 1, 1))
SELECT
   @date AS CurrentDay,
   DATEADD(day, - DATEPART(weekday, @date) + 1, @date) AS StartOfTheWeek,
   DATEADD(day, 7 - DATEPART(weekday, @date), @date) AS EndOfTheWeek

结果：

CurrentDay  StartOfTheWeek  EndOfTheWeek
2019-08-06  2019-08-05      2019-08-11

如果要定义具有计算列的表：

CREATE TABLE Data (
    [Year] int,
    [Week] int,
    [Start_Date] AS DATEADD (
        day, 
        - DATEPART(weekday, DATEADD(week, ([Week] - 1), DATEFROMPARTS([Year], 1, 1))) + 1, 
        DATEADD(week, ([Week] - 1), DATEFROMPARTS([Year], 1, 1))
    ),
    [End_Date] AS DATEADD (
        day, 
        7 - DATEPART(weekday, DATEADD(week, ([Week] - 1), DATEFROMPARTS([Year], 1, 1))),
        DATEADD(week, ([Week] - 1), DATEFROMPARTS([Year], 1, 1))
    )
)

INSERT INTO Data ([Year], [Week])
VALUES (2019, 32)

Answer 2

这可以通过STR_TO_DATE：http://www.java2s.com/Tutorial/MySQL/0280__Date-Time-Functions/Toconvertayearweektoadatethenyoushouldalsospecifytheweekday.htm

实现

SQL Server从星期数和年份中检索星期开始日期和星期结束日期

2 个答案: