As the name suggests, enabling ALLOW_INVALID_DATES SQL mode will allow us to store invalid dates in the table. The example is given below to understand it −
Example
mysql> SET sql_mode = ALLOW_INVALID_DATES;
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> Insert Into detail_bday(Name, Birth_Date) values('Sonia','1993-11-31');
Query OK, 1 row affected (0.09 sec)
mysql> Insert Into detail_bday(Name, Birth_Date) values('Ram','0000-00-00');
Query OK, 1 row affected (0.10 sec)
mysql> Select * from detail_bday;
+----+---------+------------+
| Sr | Name | Birth_Date |
+----+---------+------------+
| 1 | Saurabh | 1990-05-12 |
| 2 | Raman | 1993-06-11 |
| 3 | Gaurav | 1984-01-17 |
| 4 | Rahul | 1993-06-11 |
| 5 | Sonia | 1993-11-31 |
| 6 | Ram | 0000-00-00 |
+----+---------+------------+
6 rows in set (0.00 sec)Above result set shows that MySQL allows us to store invalid date like ‘1993-11-31’ and ‘0000-00-00’ after enabling the ALOOW_INVALID_DATES SQL mode.