DATEADD MINUTES Between Range MSSQL - sql-server

Question

I am having some difficulty in trying to figure out something, lets say I have a date and time;
And I want to add 180 minutes to it so;
SELECT DATEADD(MINUTE,180,'2018-05-24 15:00')
This would give me answer of "2018-05-24 18:00" but I want to do it in a range so ADD the minutes if you are between 09:00 - 17:00 so something like this;
SELECT DATEADD(MINUTES,180,'2018-05-24 15:00') WHERE '2018-05-24 15:00' BETWEEN '2018-05-24 09:00' AND '2018-05-24 17:00'
So the answer to this would be "2018-05-25 10:00"

Answer 1

Was hard, but this should work for all your cases. This solution works for any amount of (positive) minutes and result will always be inside the parametrized hours, adding the corresponding amount of days.
DECLARE #RangeHourStart INT = 9
DECLARE #RangeHourEnd INT = 17
DECLARE #MinutesToAdd INT = 120
DECLARE #Date DATETIME = '2018-05-24 15:00'
SELECT
FinalDate = CASE
WHEN -- When final hour exceeds the range hour
DATEPART(HOUR, #Date) * 60 +
DATEPART(MINUTE, #Date) +
#MinutesToAdd % ((#RangeHourEnd - #RangeHourStart) * 60) > #RangeHourEnd * 60
THEN
DATEADD(HOUR, -1 * (#RangeHourStart - 1),
DATEADD(DAY, 1,
DATEADD(MINUTE, #MinutesToAdd % ((#RangeHourEnd - #RangeHourStart) * 60),
DATEADD(
DAY,
#MinutesToAdd / ((#RangeHourEnd - #RangeHourStart) * 60),
#Date))))
ELSE
DATEADD(MINUTE, #MinutesToAdd % ((#RangeHourEnd - #RangeHourStart) * 60),
DATEADD(
DAY,
#MinutesToAdd / ((#RangeHourEnd - #RangeHourStart) * 60),
#Date))
END
I made it so you don't need to hard-code any value.

Answer 2

This doesn't look particularly pretty, however...
USE Sandbox;
GO
CREATE TABLE Times (DateNTime datetime2(0));
INSERT INTO Times
VALUES ('20180520 10:00:00'),
('20180520 15:20:00'),
('20180521 09:32:00'),
('20180521 14:17:00'),
('20180522 16:54:00'),
('20180523 12:46:00'),
('20180524 15:32:00');
GO
SELECT *
FROM Times;
GO
SELECT T.DateNTime,
CASE WHEN CONVERT(time,T.DateNTime) <= '14:00' THEN DATEADD(MINUTE, 180,T.DateNTime)
ELSE DATEADD(MINUTE, 180 - DATEDIFF(MINUTE,T.DateNTime,DATEADD(HOUR,17,DATEADD(DAY, DATEDIFF(DAY, 0, T.DateNTime),0))), DATEADD(HOUR,9,DATEADD(DAY, DATEDIFF(DAY, 0, T.DateNTime) + 1,0))) END
FROM Times T;
GO
DROP TABLE Times;

Answer 3

you can try this:
DECLARE #input DATETIME='2018-05-24 15:00'
DECLARE #min INT=180
SELECT CASE WHEN DATEADD(MINUTE,#min,#input)>DATEADD(HOUR, 17,DateAdd(Day, Datediff(Day,0, #input), 0))
THEN DATEADD(MINUTE,
DATEDIFF(MINUTE,
DATEADD(HOUR, 17,
DATEADD(Day,
DATEDIFF(Day,0, #input),
0)
),
DATEADD(MINUTE,#min,#input)),
DATEADD(Hour,9,
DATEADD(Day,1,
DateAdd(Day,
Datediff(Day,0, #input),
0)
)
)
)
ELSE DATEADD(MINUTE,#min,#input)
END