Oracle 21c

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ALTER SESSION SET NLS_DATE_FORMAT = 'DD-MON-YYYY HH24:MI:SS';
CREATE TABLE t1 (     
 seq_num NUMBER GENERATED BY DEFAULT AS IDENTITY (START WITH 1) NOT NULL,
   start_date   DATE,
   end_date    DATE 
);
INSERT /*+ WITH_PLSQL */ INTO t1 (start_date, end_date)
WITH 
FUNCTION random_date(
      p_from IN DATE,
      p_to   IN DATE
    ) RETURN DATE
   IS
   BEGIN
      RETURN p_from + DBMS_RANDOM.VALUE() * (p_to - p_from + 1 );
END random_date;
FUNCTION random_interval(
      p_min_hours IN NUMBER,
      p_max_hours IN NUMBER
    ) RETURN INTERVAL DAY TO SECOND
   IS
   BEGIN
      RETURN floor(dbms_random.value(p_min_hours, p_max_hours)) * interval '1' hour
        + floor(dbms_random.value(0, 60)) * interval '1' minute
        + floor(dbms_random.value(0, 60)) * interval '1' second;
END random_interval;
cte (start_date, duration) AS (
    SELECT
        random_date(DATE '2022-04-01', DATE '2022-04-30'),
        random_interval(1, 10)
    FROM dual CONNECT BY level <= 50
 )
SELECT start_date, start_date + duration
FROM cte;
50 rows affected

SELECT * FROM t1 ORDER BY start_date


SEQ_NUM
START_DATE
END_DATE


10
01-APR-2022 05:10:27
01-APR-2022 10:22:55

15
01-APR-2022 11:45:58
01-APR-2022 20:37:59

23
02-APR-2022 08:24:18
02-APR-2022 12:26:36

31
03-APR-2022 15:40:17
03-APR-2022 16:52:59

1
03-APR-2022 19:01:19
03-APR-2022 20:48:29

50
04-APR-2022 06:38:23
04-APR-2022 12:44:22

20
04-APR-2022 15:18:34
04-APR-2022 21:28:21

9
04-APR-2022 18:12:02
04-APR-2022 21:43:02

38
05-APR-2022 15:50:43
05-APR-2022 22:05:41

46
05-APR-2022 18:21:34
06-APR-2022 03:52:38

7
07-APR-2022 04:24:56
07-APR-2022 05:25:37

17
07-APR-2022 10:14:55
07-APR-2022 17:18:48

40
08-APR-2022 06:12:36
08-APR-2022 10:02:00

2
08-APR-2022 15:08:16
08-APR-2022 20:57:15

21
08-APR-2022 16:51:28
08-APR-2022 22:56:47

35
08-APR-2022 23:56:51
09-APR-2022 06:57:15

16
09-APR-2022 22:11:38
10-APR-2022 02:44:07

34
11-APR-2022 05:18:47
11-APR-2022 11:22:44

39
11-APR-2022 18:17:01
12-APR-2022 02:10:09

37
11-APR-2022 18:46:39
11-APR-2022 23:10:24

44
11-APR-2022 19:55:56
11-APR-2022 21:37:22

3
11-APR-2022 23:13:12
12-APR-2022 08:23:15

41
12-APR-2022 01:11:01
12-APR-2022 10:21:58

26
12-APR-2022 03:45:21
12-APR-2022 11:15:36

12
12-APR-2022 07:33:28
12-APR-2022 11:37:14

29
12-APR-2022 13:54:13
12-APR-2022 23:15:18

47
13-APR-2022 18:37:06
13-APR-2022 22:15:40

45
16-APR-2022 05:58:14
16-APR-2022 12:26:09

14
17-APR-2022 14:20:31
18-APR-2022 00:15:48

36
17-APR-2022 23:22:29
18-APR-2022 08:46:54

13
18-APR-2022 16:42:07
18-APR-2022 20:15:30

28
19-APR-2022 07:02:20
19-APR-2022 08:07:36

49
19-APR-2022 20:30:25
19-APR-2022 22:51:43

43
20-APR-2022 01:03:41
20-APR-2022 05:33:06

19
21-APR-2022 05:03:23
21-APR-2022 10:10:34

27
21-APR-2022 22:10:47
22-APR-2022 05:46:27

33
22-APR-2022 06:30:11
22-APR-2022 13:52:40

42
23-APR-2022 07:31:34
23-APR-2022 09:45:13

32
24-APR-2022 01:54:44
24-APR-2022 08:38:17

11
24-APR-2022 06:08:54
24-APR-2022 08:20:33

8
24-APR-2022 08:13:54
24-APR-2022 16:47:27

22
24-APR-2022 19:09:13
25-APR-2022 01:00:21

18
25-APR-2022 05:08:32
25-APR-2022 06:45:15

6
25-APR-2022 08:10:45
25-APR-2022 15:47:07

30
26-APR-2022 20:45:22
27-APR-2022 01:22:37

25
27-APR-2022 12:26:17
27-APR-2022 15:58:28

48
27-APR-2022 15:23:19
27-APR-2022 23:44:57

4
27-APR-2022 16:10:09
27-APR-2022 19:59:17

24
27-APR-2022 21:20:45
28-APR-2022 05:18:44

5
29-APR-2022 14:35:45
29-APR-2022 19:51:13

SEQ_NUM	START_DATE	END_DATE
10	01-APR-2022 05:10:27	01-APR-2022 10:22:55
15	01-APR-2022 11:45:58	01-APR-2022 20:37:59
23	02-APR-2022 08:24:18	02-APR-2022 12:26:36
31	03-APR-2022 15:40:17	03-APR-2022 16:52:59
1	03-APR-2022 19:01:19	03-APR-2022 20:48:29
50	04-APR-2022 06:38:23	04-APR-2022 12:44:22
20	04-APR-2022 15:18:34	04-APR-2022 21:28:21
9	04-APR-2022 18:12:02	04-APR-2022 21:43:02
38	05-APR-2022 15:50:43	05-APR-2022 22:05:41
46	05-APR-2022 18:21:34	06-APR-2022 03:52:38
7	07-APR-2022 04:24:56	07-APR-2022 05:25:37
17	07-APR-2022 10:14:55	07-APR-2022 17:18:48
40	08-APR-2022 06:12:36	08-APR-2022 10:02:00
2	08-APR-2022 15:08:16	08-APR-2022 20:57:15
21	08-APR-2022 16:51:28	08-APR-2022 22:56:47
35	08-APR-2022 23:56:51	09-APR-2022 06:57:15
16	09-APR-2022 22:11:38	10-APR-2022 02:44:07
34	11-APR-2022 05:18:47	11-APR-2022 11:22:44
39	11-APR-2022 18:17:01	12-APR-2022 02:10:09
37	11-APR-2022 18:46:39	11-APR-2022 23:10:24
44	11-APR-2022 19:55:56	11-APR-2022 21:37:22
3	11-APR-2022 23:13:12	12-APR-2022 08:23:15
41	12-APR-2022 01:11:01	12-APR-2022 10:21:58
26	12-APR-2022 03:45:21	12-APR-2022 11:15:36
12	12-APR-2022 07:33:28	12-APR-2022 11:37:14
29	12-APR-2022 13:54:13	12-APR-2022 23:15:18
47	13-APR-2022 18:37:06	13-APR-2022 22:15:40
45	16-APR-2022 05:58:14	16-APR-2022 12:26:09
14	17-APR-2022 14:20:31	18-APR-2022 00:15:48
36	17-APR-2022 23:22:29	18-APR-2022 08:46:54
13	18-APR-2022 16:42:07	18-APR-2022 20:15:30
28	19-APR-2022 07:02:20	19-APR-2022 08:07:36
49	19-APR-2022 20:30:25	19-APR-2022 22:51:43
43	20-APR-2022 01:03:41	20-APR-2022 05:33:06
19	21-APR-2022 05:03:23	21-APR-2022 10:10:34
27	21-APR-2022 22:10:47	22-APR-2022 05:46:27
33	22-APR-2022 06:30:11	22-APR-2022 13:52:40
42	23-APR-2022 07:31:34	23-APR-2022 09:45:13
32	24-APR-2022 01:54:44	24-APR-2022 08:38:17
11	24-APR-2022 06:08:54	24-APR-2022 08:20:33
8	24-APR-2022 08:13:54	24-APR-2022 16:47:27
22	24-APR-2022 19:09:13	25-APR-2022 01:00:21
18	25-APR-2022 05:08:32	25-APR-2022 06:45:15
6	25-APR-2022 08:10:45	25-APR-2022 15:47:07
30	26-APR-2022 20:45:22	27-APR-2022 01:22:37
25	27-APR-2022 12:26:17	27-APR-2022 15:58:28
48	27-APR-2022 15:23:19	27-APR-2022 23:44:57
4	27-APR-2022 16:10:09	27-APR-2022 19:59:17
24	27-APR-2022 21:20:45	28-APR-2022 05:18:44
5	29-APR-2022 14:35:45	29-APR-2022 19:51:13