An out-of-range datetime value (with a 5-digit year) can be created and cause troubles

create table t1 (d datetime);

# Query OK, 0 rows affected (0.22 sec)

insert into t1 values ('9999-12-31 23:59:59');

# Query OK, 1 row affected (0.00 sec)

update t1 set d = addtime(d, '00:00:01');

# Query OK, 1 row affected (0.00 sec)

# Rows matched: 1  Changed: 1  Warnings: 0

select * from t1 where d > '9999-12-31 23:59:59';

# +---------------------+

# | d                   |

# +---------------------+

# | :000-01-01 00:00:00 |

# +---------------------+

# 1 row in set (0.00 sec)