MySQL 8.0

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select version();


version()


8.0.27


CREATE TABLE table1 (
id INT, start_date DATE, end_date DATE, amount INT);

INSERT INTO table1 VALUES 
(1,'2021-01-01','2021-01-07',100);
WITH RECURSIVE cte AS (
SELECT id, start_date, end_date, amount, start_date AS operation_date 
FROM table1 
 UNION ALL
SELECT id, start_date, end_date, amount, operation_date+INTERVAL 1 DAY 
FROM cte 
 WHERE operation_date+INTERVAL 1 DAY <= end_date)
  SELECT * 
    FROM cte ;


id
start_date
end_date
amount
operation_date


1
2021-01-01
2021-01-07
100
2021-01-01

1
2021-01-01
2021-01-07
100
2021-01-02

1
2021-01-01
2021-01-07
100
2021-01-03

1
2021-01-01
2021-01-07
100
2021-01-04

1
2021-01-01
2021-01-07
100
2021-01-05

1
2021-01-01
2021-01-07
100
2021-01-06

1
2021-01-01
2021-01-07
100
2021-01-07

id	start_date	end_date	amount	operation_date
1	2021-01-01	2021-01-07	100	2021-01-01
1	2021-01-01	2021-01-07	100	2021-01-02
1	2021-01-01	2021-01-07	100	2021-01-03
1	2021-01-01	2021-01-07	100	2021-01-04
1	2021-01-01	2021-01-07	100	2021-01-05
1	2021-01-01	2021-01-07	100	2021-01-06
1	2021-01-01	2021-01-07	100	2021-01-07