Oracle 21c

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ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
Create table tab1 (col1, col2, date_col, quantity) as 
SELECT 'I1','L1',DATE '2024-07-01',10 FROM DUAL UNION ALL
SELECT 'I1','L1',DATE '2024-07-02',10 FROM DUAL UNION ALL
SELECT 'I1','L1',DATE '2024-07-03',10 FROM DUAL UNION ALL
SELECT 'I1','L1',DATE '2024-07-12',10 FROM DUAL UNION ALL
SELECT 'I1','L1',DATE '2024-07-13',10 FROM DUAL UNION ALL
SELECT 'I1','L1',DATE '2024-07-14',10 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-05',26 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-06',26 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-07',26 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-08',26 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-10',34 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-11',34 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-12',28 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-13',28 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-14',28 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-21',20 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-22',20 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-23',20 FROM DUAL UNION ALL
SELECT 'I2','L2',DATE '2024-07-24',20 FROM DUAL;
19 rows affected

SELECT *
FROM   tab1
       MATCH_RECOGNIZE(
         PARTITION BY col1, col2
         ORDER BY date_col
         MEASURES
           FIRST(quantity) AS quantity,
           FIRST(date_col) AS start_date,
           LAST(date_col) AS end_date
         PATTERN (first_row consecutive*)
         DEFINE
           consecutive AS  quantity = FIRST(quantity)
                       AND date_col <= PREV(date_col) + INTERVAL '1' DAY
       )


COL1
COL2
QUANTITY
START_DATE
END_DATE


I1
L1
10
2024-07-01 00:00:00
2024-07-03 00:00:00

I1
L1
10
2024-07-12 00:00:00
2024-07-14 00:00:00

I2
L2
26
2024-07-05 00:00:00
2024-07-08 00:00:00

I2
L2
34
2024-07-10 00:00:00
2024-07-11 00:00:00

I2
L2
28
2024-07-12 00:00:00
2024-07-14 00:00:00

I2
L2
20
2024-07-21 00:00:00
2024-07-24 00:00:00

COL1	COL2	QUANTITY	START_DATE	END_DATE
I1	L1	10	2024-07-01 00:00:00	2024-07-03 00:00:00
I1	L1	10	2024-07-12 00:00:00	2024-07-14 00:00:00
I2	L2	26	2024-07-05 00:00:00	2024-07-08 00:00:00
I2	L2	34	2024-07-10 00:00:00	2024-07-11 00:00:00
I2	L2	28	2024-07-12 00:00:00	2024-07-14 00:00:00
I2	L2	20	2024-07-21 00:00:00	2024-07-24 00:00:00