I have 3 columns, employee_id, start_time and end_time i want to make bucks of 1 hours to show me how many employees were working in each hour. For example, employee A worked from 12pm to 3pm and employee B worked from 2pm to 4pm so, at 12m (1 employee was working) 1pm (1 employee) 2pm (2 employees were working) 3pm (2employees) and 4pm (1epmloyees), how can i make this in SQL? Let me show you a picture of the start and end time columns.
Sample input would be:
Expected outcome would be something like
I want to create a bucket in order to know how many people were working in each hour of the day.
SELECT
Employee_id,
TIME(shift_start_at,timezone) AS shift_start,
TIME(shift_end_at,timezone) AS shift_end,
FROM
`employee_shifts` AS shifts
WHERE
DATE(shifts.shift_start_at_local) >= "2022-05-01"
GROUP BY
1,
2,
3
CodePudding user response:
Assuming you are on mysql version 8 or above generate all the buckets , left join to shifts to infill times in start-endtime ranges , filter out those that are not applicable then count eg:-
DROP TABLE IF EXISTS t;
create table t (id int, startts datetime, endts datetime);
insert into t values
(1,'2022-06-19 08:30:00','2022-06-19 10:00:00'),
(2,'2022-06-19 08:30:00','2022-06-19 08:45:00'),
(3,'2022-06-19 07:00:00','2022-06-19 07:59:00');
with cte as
(select 7 as bucket union select 8 union select 9 union select 10 union select 11),
cte1 as
(select bucket,t.*,
floor(hour(startts)) starthour, floor(hour(endts)) endhour
from cte
left join t on cte.bucket between floor(hour(startts)) and floor(hour(endts))
)
select bucket,count(id) nof from cte1 group by bucket
;
-------- -----
| bucket | nof |
-------- -----
| 7 | 1 |
| 8 | 2 |
| 9 | 1 |
| 10 | 1 |
| 11 | 0 |
-------- -----
5 rows in set (0.001 sec)
CodePudding user response:
Just use a subquery for each column mentioning the required timestamp in between, also make sure your start_time and end_time columns are timestamp types. For more information, please share the table structure, sample data, and expected output
CodePudding user response:
If I understood well, this would be
SELECT HOUR, (SELECT COUNT(*)
FROM employee
WHERE start_time <= HOUR
AND end_time >= HOUR) AS working
FROM schedule HOUR
Where schedule is a table with employee schedules.