Reputation: 307
I am creating a query that shows me the time elapsed between two dates, only taking into account only the one that is Monday through Friday from 08:00 to 17:00, for example:
For example, if a petition opens on day 1 at 6:30 p.m. and closes on day 2 at 8:45 p.m., the TMO is 45 minutes. If it closes on day 3 at 8:45, the TMO is 9 hours and 45 minutes.
Example 2: If a petition opens on Friday at 16:45 and closes on Tuesday at 8:30, the MTO would be: 15 minutes on Friday, nine hours on Monday and 30 minutes on Tuesday for an MTO = 9 hours 45 minutes
The query is performed on a single column of type date as I show below
I currently use a LAG function to make the query, but I can not create something functional, not even optimal to incorporate, I would greatly appreciate your help.
Upvotes: 0
Views: 131
Reputation:
In the solution below I will ignore the "lag" part of your problem, which you said you know how to use. I am only showing how to count "working hours" between any two date_times (they may be during or before or after work hours, and/or they can be on weekend days; the computation is the same in all cases).
Explaining the answer in words: For two given date-times, "start" and "end", calculate how many "work" hours elapsed from the beginning of the week (from Monday 00:00:00) till each of them. This is in fact a calculation for ONE date, not for TWO dates. Then: given "start" and "end", calculate this number of hours for each of them; subtract the "end" number of hours from the "start" number of hours. To the result, add x times 5 times 9, where x is the difference in weeks between Monday 00:00:00 of the two dates. (If they are in the same week, the difference will be 0.)
To truncate a date to the beginning of the day, we use TRUNC(dt)
. To truncate to the beginning of Monday, TRUNC(dt, 'iw')
.
To compute how many "work" hours are from the beginning of the date dt
until the actual time-of-day we can use the calculation
greatest(0, least(17/24, dt - trunc(dt)) - 8/24)
(the results will be in days; we calculate everything in days and then we can convert to hours). However, in the final formula we must check to see if the date is a Saturday or Sunday, in which case this should just be zero. Or, better, we can adjust the calculation a bit later, when we count from the beginning of Monday (we can use least( 5*9/24, ...)
).
Putting everything together:
with
inputs ( dt1, dt2 ) as (
select to_date('2017-09-25 11:30:00', 'yyyy-mm-dd hh24:mi:ss'),
to_date('2017-10-01 22:45:00', 'yyyy-mm-dd hh24:mi:ss')
from dual
)
-- End of SIMULATED input dates (for testing only).
select 24 *
( least(5 * (17 - 8) / 24, greatest(0, least(17/24, dt2 - trunc(dt2)) - 8/24)
+ (17 - 8) / 24 * (trunc(dt2) - trunc(dt2, 'iw')))
-
least(5 * (17 - 8) / 24, greatest(0, least(17/24, dt1 - trunc(dt1)) - 8/24)
+ (17 - 8) / 24 * (trunc(dt1) - trunc(dt1, 'iw')))
+ 5 * (17 - 8) / 24 * (trunc(dt2, 'iw') - trunc(dt1, 'iw')) / 7
)
as duration_in_hours
from inputs
;
DURATION_IN_HOURS
-----------------
41.500
Upvotes: 1