tsql: How to retrieve the last date of each month between given date range

Question

I have two date for example 08/08/2013 and 11/11/2013 and I need last date of each month starting from August to November in a table so that i can iterate over the table to

Answer 1

I've created a table variable, filled it with all days between @startDate and @endDate and searched for max date in the month.

declare @tmpTable table (dates date)
declare @startDate date = '08/08/2013'
declare @endDate date = '11/11/2013'

while @startDate <= @endDate
begin
    insert into @tmpTable (dates) values (@startDate)
    set @startDate = DATEADD(DAY, 1, @startDate)
end

select max(dates) as [Last day] from @tmpTable as o
group by datepart(YEAR, dates), datepart(MONTH, dates)

Results:

Last day
2013-08-31
2013-09-30
2013-10-31
2013-11-11

To also get last day of November this can be used before loop:

set @endDate = DATEADD(day, -1, DATEADD(month, DATEDIFF(month, 0, @endDate) + 1, 0))

Answer 2

You can use a recursive CTE to do this, note the MAXRECURSION OPTION prevents an infinite loop:

DECLARE @StartDate DATE = '2013-08-08'
DECLARE @EndDate DATE = '2013-11-11'

;WITH dateCTE
AS
(
    SELECT CAST(DATEADD(M, 1,DATEADD(d, DAY(@StartDate) * -1, @StartDate)) AS DATE) EndOFMonth
    UNION ALL 
    SELECT CAST(DATEADD(M, 2,DATEADD(d, DAY(EndOFMonth) * -1, EndOFMonth)) AS DATE) 
    FROM dateCTE
    WHERE EndOFMonth < DATEADD(d, DAY(@EndDate) * -1, @EndDate)

)
SELECT *
FROM dateCTE
OPTION (MAXRECURSION 30);

This returns

EndOFMonth
----------
2013-08-31
2013-09-30
2013-10-31

Answer 3

Although the question is about the last day which @bummi has already answered.

But here is the solution for the first date which might be helpful for someone.

Get the first dates of all the months in-between the @FromDate and @ToDate.

DECLARE @FromDate DATETIME = '2019-08-13'
DECLARE @ToDate DATETIME = '2019-11-25'

;WITH CTE
AS 
(
    SELECT DATEADD(DAY, -(DAY(@FromDate) - 1), @FromDate) AS FirstDateOfMonth

    UNION ALL

    SELECT DATEADD(MONTH, 1, FirstDateOfMonth)
    FROM CTE
    WHERE FirstDateOfMonth < DATEADD(DAY, -(DAY(@ToDate) - 1), @ToDate)
)
SELECT * FROM CTE

Here is the result

--Result
2019-08-01 00:00:00.000
2019-09-01 00:00:00.000
2019-10-01 00:00:00.000
2019-11-01 00:00:00.000