The only MyIsam-only functionality that I can think of is the ability to have a compound primary key EG
PRIMARY KEY (year, number)
where the 2nd part auto_increments within the first part, so if you have
CREATE TABLE `test1` (
`year` int(11) NOT NULL,
`number` int(11) NOT NULL AUTO_INCREMENT,
PRIMARY KEY (`year`,`number`)
) ENGINE=MyISAM ;
mysql> select * from test1;
+------+--------+
| year | number |
+------+--------+
| 2022 | 1 |
| 2022 | 2 |
+------+--------+
mysql> insert into test1 (year) values (2022), (2022), (2023), (2023), (2024);
mysql> select * from test1;
+------+--------+
| year | number |
+------+--------+
| 2022 | 1 |
| 2022 | 2 |
| 2022 | 3 |
| 2022 | 4 |
| 2023 | 1 |
| 2023 | 2 |
| 2024 | 1 |
+------+--------+