MySQL 8.0

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create table orders (orderDate date);
insert into orders values (CURDATE());
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 1 MONTH));
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 2 MONTH));
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 3 MONTH));
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 4 MONTH));
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 40 MONTH));
insert into orders values (DATE_SUB(CURDATE(), INTERVAL 400 MONTH));
SELECT orderDate FROM orders;

orderDate

2024-07-04

2024-06-04

2024-05-04

2024-04-04

2024-03-04

2021-03-04

1991-03-04

DELETE FROM orders
WHERE orderDate <= 
  DATE_SUB(CURDATE(), INTERVAL 3 MONTH);
SELECT orderDate FROM orders;

orderDate

2024-07-04

2024-06-04

2024-05-04