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create table SHIFT_LOG_ENTRY (
SHIFT_LOG_DET_ID integer,
ENTRY_TIME timestamp
)
insert into SHIFT_LOG_ENTRY(SHIFT_LOG_DET_ID, ENTRY_TIME) values (1, timestamp'2019-09-19 16:13:00');
1 rows affected
insert into SHIFT_LOG_ENTRY(SHIFT_LOG_DET_ID, ENTRY_TIME) values (1, timestamp'2019-09-19 16:32:00');
1 rows affected
insert into SHIFT_LOG_ENTRY(SHIFT_LOG_DET_ID, ENTRY_TIME) values (1, timestamp'2019-09-19 16:45:00');
1 rows affected
select
SHIFT_LOG_DET_ID,
ENTRY_TIME,
datediff(minute from ENTRY_TIME to NEXT_ENTRY_TIME) as DURATION
from (
select
a.SHIFT_LOG_DET_ID,
a.ENTRY_TIME,
(select min(ENTRY_TIME)
from SHIFT_LOG_ENTRY
where SHIFT_LOG_DET_ID = a.SHIFT_LOG_DET_ID
and ENTRY_TIME > a.ENTRY_TIME) as NEXT_ENTRY_TIME
from SHIFT_LOG_ENTRY a
) b
| SHIFT_LOG_DET_ID | ENTRY_TIME | DURATION |
|---|---|---|
| 1 | 2019-09-19 16:13:00 | 19 |
| 1 | 2019-09-19 16:32:00 | 13 |
| 1 | 2019-09-19 16:45:00 | null |
select
SHIFT_LOG_DET_ID,
ENTRY_TIME,
datediff(minute from ENTRY_TIME to lead(ENTRY_TIME) over (partition by SHIFT_LOG_DET_ID order by ENTRY_TIME)) as DURATION
from SHIFT_LOG_ENTRY
| SHIFT_LOG_DET_ID | ENTRY_TIME | DURATION |
|---|---|---|
| 1 | 2019-09-19 16:13:00 | 19 |
| 1 | 2019-09-19 16:32:00 | 13 |
| 1 | 2019-09-19 16:45:00 | null |