time range between 2 dates - sql

Question

I have following script
with first_step as
(
SELECT
1 as MY_TYPE,
2373 as my_id
,to_date('15.02.23 17:00' , 'dd.mm.yyyy HH24:MI') AS time_from
,to_date('17.02.23 12:00' , 'dd.mm.yyyy HH24:MI')AS time_till
from dual
union all
SELECT
1 as MY_TYPE,
2373 as my_id
,to_date('16.02.23 14:00' , 'dd.mm.yyyy HH24:MI') AS time_from
,to_date('16.02.23 15:00' , 'dd.mm.yyyy HH24:MI')AS time_till
from dual
union all
SELECT
0 as MY_TYPE,
2373 as my_id
,to_date('14.02.23 22:00' , 'dd.mm.yyyy HH24:MI') AS time_from
,to_date('16.02.23 18:00' , 'dd.mm.yyyy HH24:MI')AS time_till
from dual
),
second_step as
(
select
MY_TYPE,
my_id,
to_date(to_char(time_from +(column_value-1), 'dd.mm.yyyy'),'dd.mm.yyyy') AS my_date,
case when trunc(time_from) < to_date(to_char(time_from +(column_value-1), 'dd.mm.yyyy'),'dd.mm.yyyy') then '00:00' else to_char(time_from,'HH24:MI') end time_from,
case when trunc(time_till) > to_date(to_char(time_from +(column_value-1), 'dd.mm.yyyy'),'dd.mm.yyyy') then '23:59' else replace(to_char(time_till,'HH24:MI'),'00:00','23:59') end time_till
from first_step
CROSS JOIN TABLE ( CAST(MULTISET(
SELECT
level
from
dual
CONNECT BY time_from + level-1 <= time_till
) AS sys.odcinumberlist) ) n
)
select * from second_step
order by
my_date,time_from, time_till
that is what I get
But I need that
So, we have entries which are on the same day, but also entries lasting multiple days. The single day entries should stay as they are, but the multiple days should be stretched.Currently my multiple days entries are not represented correctly. What is wrong with my script?

Answer 1

You can use a recursive query:
with first_step (my_type, my_id, time_from, time_till) as (
SELECT 1,
2373,
to_date('15.02.2023 17:00', 'dd.mm.yyyy HH24:MI'),
to_date('17.02.2023 12:00', 'dd.mm.yyyy HH24:MI')
from dual
union all
SELECT 1,
2373,
to_date('16.02.2023 14:00', 'dd.mm.yyyy HH24:MI'),
to_date('16.02.2023 15:00', 'dd.mm.yyyy HH24:MI')
from dual
union all
SELECT 0,
2373,
to_date('14.02.2023 22:00', 'dd.mm.yyyy HH24:MI'),
to_date('16.02.2023 18:00', 'dd.mm.yyyy HH24:MI')
from dual
),
days (my_type, my_id, time_from, day_end, time_till) AS (
SELECT my_type,
my_id,
time_from,
TRUNC(time_from) + INTERVAL '23:59:59' HOUR TO SECOND,
time_till
FROM first_step
UNION ALL
SELECT my_type,
my_id,
day_end + INTERVAL '1' SECOND,
day_end + INTERVAL '1' DAY,
time_till
FROM days
WHERE day_end < time_till
)
SELECT my_type,
my_id,
time_from,
LEAST(day_end, time_till) AS time_till
FROM days
ORDER BY my_id, time_from, time_till;
Or a hierarchical query:
with first_step (my_type, my_id, time_from, time_till) as (
SELECT 1,
2373,
to_date('15.02.2023 17:00', 'dd.mm.yyyy HH24:MI'),
to_date('17.02.2023 12:00', 'dd.mm.yyyy HH24:MI')
from dual
union all
SELECT 1,
2373,
to_date('16.02.2023 14:00', 'dd.mm.yyyy HH24:MI'),
to_date('16.02.2023 15:00', 'dd.mm.yyyy HH24:MI')
from dual
union all
SELECT 0,
2373,
to_date('14.02.2023 22:00', 'dd.mm.yyyy HH24:MI'),
to_date('16.02.2023 18:00', 'dd.mm.yyyy HH24:MI')
from dual
)
SELECT my_type,
my_id,
GREATEST(time_from, day_start) AS time_from,
LEAST(time_till, day_end) AS time_till
FROM first_step f
CROSS JOIN LATERAL (
SELECT TRUNC(f.time_from) + LEVEL - INTERVAL '1' DAY AS day_start,
TRUNC(f.time_from) + LEVEL - INTERVAL '1' SECOND AS day_end
FROM dual
CONNECT BY TRUNC(f.time_from) + LEVEL - 1 < f.time_till
)
ORDER BY my_id, time_from, time_till
Which both output:
MY_TYPE
MY_ID
TIME_FROM
TIME_TILL
0
2373
2023-02-14 22:00:00
2023-02-14 23:59:59
0
2373
2023-02-15 00:00:00
2023-02-15 23:59:59
1
2373
2023-02-15 17:00:00
2023-02-15 23:59:59
0
2373
2023-02-16 00:00:00
2023-02-16 18:00:00
1
2373
2023-02-16 00:00:00
2023-02-16 23:59:59
1
2373
2023-02-16 14:00:00
2023-02-16 15:00:00
1
2373
2023-02-17 00:00:00
2023-02-17 12:00:00
Note: to_date('16.02.23 14:00', 'dd.mm.yyyy HH24:MI') will give you the year 0023 and not 2023. If you want 2023 then use a 4-digit year or the format model RR or YY.
fiddle