How to find the number of remaining days in a month based off a week number?

Question

I have a week number, like 32, and I need get the number of days left in the month starting from this week. How can I do in SQL Server?

I need to get the month of this weekNumber. Then i need to know the for Week number 32 remaining days of the respective month. — user3510330, Aug 09 '17 at 08:41
Possible duplicate of [Get dates from a week number in T-SQL](https://stackoverflow.com/questions/607817/get-dates-from-a-week-number-in-t-sql) — GSerg, Aug 09 '17 at 08:44
You should update your question, with what you really need, and some example output. Unless a specific week only has 1 day, the days left in the month is non-deterministic. — Peter Abolins, Aug 09 '17 at 08:46

score 0 · Answer 1 · answered Aug 09 '17 at 08:41

0

Try DATEPART ( datepart , date ) and datepart can be weekday, day, month or something like that..

Visit this https://technet.microsoft.com/en-us/library/ms174420(v=sql.105).aspx

answered Aug 09 '17 at 08:41

flowers1234

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score 0 · Answer 2 · answered Aug 09 '17 at 13:49

First, you need to find the first day of the week number in question. In order to do this, we need to know what year you want as well. In the example below, I use the current year. Once this is done, then we can use DATEDIFF() to find the days left, from the start of the week number you passed in, to the end of the month.

DECLARE @WeekNo int= 32
DECLARE @Year int=datepart(year,getdate())

SELECT 
    FirstDayOfWeek =  DATEADD(wk,@WeekNo-1,DATEADD(yy,@Year-1900,0))
    ,LastDayOfMonth = DATEADD(d, -1, DATEADD(m, DATEDIFF(m, 0, DATEADD(wk,@WeekNo-1,DATEADD(yy,@Year-1900,0))) + 1, 0))
    ,DaysLeftInMonth = DATEDIFF(day,DATEADD(wk,@WeekNo-1,DATEADD(yy,@Year-1900,0)),DATEADD(d, -1, DATEADD(m, DATEDIFF(m, 0, DATEADD(wk,@WeekNo-1,DATEADD(yy,@Year-1900,0))) + 1, 0)))

How to find the number of remaining days in a month based off a week number?

2 Answers2