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CREATE TABLE test (id INT, start_date DATE, end_date DATE, frequency INT);
INSERT INTO test VALUES
(1, '2020-11-23', '2021-06-21', 1),
(2, '2020-11-19', '2021-03-20', 2);
Records: 2 Duplicates: 0 Warnings: 0
WITH RECURSIVE
cte AS ( SELECT id, start_date, end_date, frequency
FROM test
UNION ALL
SELECT id, start_date + INTERVAL frequency MONTH, end_date, frequency
FROM cte
WHERE start_date <= end_date )
SELECT id, start_date `date`
FROM cte
WHERE start_date <= end_date
ORDER BY 1,2
| id | date |
|---|---|
| 1 | 2020-11-23 |
| 1 | 2020-12-23 |
| 1 | 2021-01-23 |
| 1 | 2021-02-23 |
| 1 | 2021-03-23 |
| 1 | 2021-04-23 |
| 1 | 2021-05-23 |
| 2 | 2020-11-19 |
| 2 | 2021-01-19 |
| 2 | 2021-03-19 |