Sql Server - Comparing time only in 24 hour format? - sql

Question

I want to compare time with a time-range and if that particular time lies with-in that time-range, then it should return a record.
For example, Table 'A' has :
+-----------+------+-------------+-----------+
| User_Code | Name | Shift_Start | Shift_End |
+-----------+------+-------------+-----------+
| 1 | ABC | 04:01:00 | 11:00:00 |
| 2 | DEF | 11:01:00 | 20:00:00 |
| 3 | XYZ | 20:01:00 | 04:00:00 |
+-----------+------+-------------+-----------+
Now I want to check whose shift was it at this specific datetime : 2016-09-26 02:51:59. The SQL query should return the User_Code = 3. Shift_Start and Shift_End are of type time.
I have tried converting 2016-09-26 02:51:59 to time and then comparing with shift_start and shift_end using between and using logical operator but I am unable to get the desired result.
This has got me baffled. Its been an hour since I have tried coming up with a solution but I am unable to do so. Tried googling but got nothing there too. Any help will be appreciated. Using SQL Server 2012.

Answer 1

You need a more complicated where condition, because the shift times can be in either order.
So:
where ((shift_start < shift_end) and
cast(#datetime as time) between shift_start and shift_end)
) or
((shift_start > shift_end) and
cast(#datetime as time) not between shift_end and shift_start)
)

Answer 2

declare #t table(
User_Code int,
Name varchar(20),
Shift_Start time,
Shift_End time
);
insert #t(User_Code,Name,Shift_Start,Shift_End)
values
(1,'ABC','04:01:00','11:00:00')
,(2,'DEF','11:01:00','20:00:00')
,(3,'XYZ','20:01:00','04:00:00');
Try
declare #d datetime = '2016-09-26 02:51:59';
select *
from #t
cross apply ( -- intermediate vars: rounded param
select dt = cast(cast(#d as date) as datetime)
) r
where #d between dateadd(d, case when Shift_Start<Shift_End then 0 else -1 end, dt) + cast(Shift_start as datetime)
and dt+cast(Shift_end as datetime);

Answer 3

Approach from the other angle and add the date part of your search criteria to the Shift Start and End Times:
Note the case statement, this handles the situation where the shift end crosses midnight.
DECLARE #dateTime DATETIME = '2016-09-26 02:51:59'
-- Remove the time portion of above
DECLARE #datePortion DATETIME = DATEADD(dd, 0, DATEDIFF(dd, 0, #dateTime))
SELECT * FROM TableA
WHERE #dateTime BETWEEN #datePortion + cast(Shift_Start as datetime)
AND CASE WHEN ShiftEnd < ShiftStart
THEN DATEADD(day, 1, #datePortion)
ELSE #datePortion
END + cast(Shift_End as datetime)