Utilizza una clausola ricorsiva di factoring sottoquery per generare ogni giorno entro i tuoi intervalli di tempo e quindi correlalo con i tuoi turni per limitare il tempo di ogni giorno in modo che rientri nelle ore di turno e quindi aggrega per ottenere il totale:
Impostazione Oracle 18 :
CREATE TABLE times ( start_date, End_Date ) AS
SELECT DATE '2017-02-21' + INTERVAL '07:52:32' HOUR TO SECOND,
DATE '2017-02-22' + INTERVAL '09:56:32' HOUR TO SECOND
FROM DUAL
UNION ALL
SELECT DATE '2017-02-21' + INTERVAL '09:52:32' HOUR TO SECOND,
DATE '2017-02-23' + INTERVAL '17:52:32' HOUR TO SECOND
FROM DUAL;
CREATE TABLE weekly_shifts ( shift_day, Start_Time, End_Time ) AS
SELECT 'MON', INTERVAL '09:00' HOUR TO MINUTE, INTERVAL '18:00' HOUR TO MINUTE FROM DUAL UNION ALL
SELECT 'TUE', INTERVAL '10:00' HOUR TO MINUTE, INTERVAL '19:00' HOUR TO MINUTE FROM DUAL UNION ALL
SELECT 'WED', INTERVAL '09:00' HOUR TO MINUTE, INTERVAL '18:00' HOUR TO MINUTE FROM DUAL UNION ALL
SELECT 'THU', INTERVAL '10:00' HOUR TO MINUTE, INTERVAL '19:00' HOUR TO MINUTE FROM DUAL UNION ALL
SELECT 'FRI', INTERVAL '09:00' HOUR TO MINUTE, INTERVAL '18:00' HOUR TO MINUTE FROM DUAL;
Query 1 :
WITH days ( id, start_date, day_start, day_end, end_date ) AS (
SELECT ROWNUM,
start_date,
start_date,
LEAST( TRUNC( start_date ) + INTERVAL '1' DAY, end_date ),
end_date
FROM times
UNION ALL
SELECT id,
start_date,
day_end,
LEAST( day_end + INTERVAL '1' DAY, end_date ),
end_date
FROM days
WHERE day_end < end_date
)
SELECT start_date,
end_date,
SUM( shift_end - shift_start ) AS days_worked_on_shift
FROM (
SELECT ID,
start_date,
end_date,
GREATEST( day_start, TRUNC( day_start ) + start_time ) AS shift_start,
LEAST( day_end, TRUNC( day_start ) + end_time ) AS shift_end
FROM days d
INNER JOIN
weekly_shifts w
ON ( TO_CHAR( d.day_start, 'DY' ) = w.shift_day )
)
GROUP BY id, start_date, end_date;
Risultato :
START_DATE END_DATE DAYS_WORKED_ON_SHIFT
------------------- ------------------- --------------------
2017-02-21 07:52:32 2017-02-22 09:56:32 0.414259259259259259
2017-02-21 09:52:32 2017-02-23 17:52:32 1.078148148148148148