SQLite 3.27

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CREATE TABLE MYTABLE (
  id INTEGER PRIMARY KEY,                   
  created TEXT,
  modified TEXT,
  anotherfield TEXT
);
✓
INSERT INTO MYTABLE (created, modified, anotherfield) VALUES
  ('2020-12-31', '2021-01-27', 'text')
✓
SELECT * FROM MYTABLE


id
created
modified
anotherfield


1
2020-12-31
2021-01-27
text


WITH RECURSIVE cte AS (
  SELECT created, modified, anotherfield, 1 x  
  FROM MYTABLE 
  WHERE id = 1
  UNION ALL 
  SELECT created, modified, anotherfield, x + 1 
  FROM cte 
  WHERE x < 3
)
INSERT INTO MYTABLE (created, modified, anotherfield)
SELECT created, modified, anotherfield 
FROM cte;
✓
SELECT * FROM MYTABLE


id
created
modified
anotherfield


1
2020-12-31
2021-01-27
text

2
2020-12-31
2021-01-27
text

3
2020-12-31
2021-01-27
text

4
2020-12-31
2021-01-27
text

id	created	modified	anotherfield
1	2020-12-31	2021-01-27	text
2	2020-12-31	2021-01-27	text
3	2020-12-31	2021-01-27	text
4	2020-12-31	2021-01-27	text