Check Time Range Lapse in Other Time Range - sql

Question

I have a Time In and Time Out and there is a time range defined for Lunch Breakfast and Dinner. What i want is to Subtract these times from the attendance time (Time In And Time Out).
The sample data is
Attendance Table Data
EMPID 1095
TimeIN 2017-03-01 08:52:45.000
TimeOut 2017-03-01 19:59:18.000
The Mess Timings are
type StartTime EndTime
BreakFast 06:30:39 10:00:39
Dinner 19:00:39 21:00:39
Lunch 12:00:23 15:00:23
What i need is to subtract these mess timings from the actual attendance time to get actual employee duty time.
Thanks.

Answer 1

This approach utilises a numbers table to create a lookup table of all the seconds between your #TimeIn and #TimeOut values. This will work for periods covering multiple days, albeit with some severe caveats:
Breakfast, Lunch and Dinner are at the same time every day.
Your #TimeIn and #TimeOut period doesn't get so big it overflows the int value that contains the number of seconds.
In that case you will need to either just use minutes or find a different method
Your return value is less than 24 hours.
In that case, just don't return the difference as a time data type and handle it accordingly.
declare #TimeIn datetime = '2017-03-01 08:52:45.000'
,#TimeOut datetime = '2017-03-01 19:59:18.000'
,#BStart time = '06:30:39'
,#BEnd time = '10:00:39'
,#LStart time = '12:00:23'
,#LEnd time = '15:00:23'
,#DStart time = '19:00:39'
,#DEnd time = '21:00:39';
-- Create numbers table then use it to build a table os seconds between TimeIn and TimeOut
with n(n) as (select n from (values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) as n(n))
,s(s) as (select top (select datediff(s,#TimeIn,#TimeOut)+1) dateadd(s,row_number() over (order by (select 1))-1,#TimeIn) from n n1,n n2,n n3,n n4,n n5,n n6)
select cast(dateadd(s,count(1),0) as time) as s
from s
where s between #TimeIn and #TimeOut -- Return all seconds that aren't within Breakfast, Lunch or Dinner
and cast(s as time) not between #BStart and #BEnd
and cast(s as time) not between #LStart and #LEnd
and cast(s as time) not between #DStart and #DEnd
Which returns: 05:59:58.0000000

Answer 2

I have daily timings of mess in other table so i created a view and took all fields in front of daily attendance then using case statement to match the timings with Daily Attendance Time.
EmployeeID AttendanceDate ShiftID TimeIn TimeOut BreakOut BreakIn LeaveType TotalHours LeaveHours ATOThours DeductedHrs OTHours UserID AudtDate Reason SM SY OTDed DutyDed Mark Expr1 MARKL BreakFastStart BreakFastEnd LunchStart LunchEnd DinnerStart DinnerEnd
1095 2017-03-01 00:00:00.000 1 2017-03-01 08:52:45.000 2017-03-01 19:59:18.000 NULL NULL NULL 0 NULL 0 0 0 NULL NULL NULL 3 2017 NULL NULL NULL NULL NULL 2017-02-20 06:30:34.000 2017-02-20 09:30:34.000 2017-02-20 12:00:26.000 2017-02-20 15:00:26.000 2017-02-20 19:00:59.000 2017-02-20 21:00:59.000
For now it's good will check it's credibility with the passage of time.
Thanks For the support

Answer 3

You can also use the following script in the View OR in JOIN query of the tables. Note I got a different answer which I think is correct.
SELECT CONVERT(varchar, DATEADD(ss,
(DATEDIFF(ss,TimeIn, [TimeOut]) -
(
DATEDIFF(ss,[BreakFastStartTime], [BreakFastEndTime]) +
DATEDIFF(ss,[LunchStartTime], [LunchEndTime]) +
DATEDIFF(ss,[DinnerStartTime], [DinnerEndTime])
)
), 0), 108)
FROM [Attendance Data]
For your example, answer is 02:36:33