By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
| id | birthdate |
|---|---|
| 1 | 1991-01-23 |
| 2 | yyyy-01-23 |
| 3 | 1991-mm-23 |
| 4 | 1991-01-dd |
| 5 | |
| 6 | 1991-01-d3 |
| 7 | 1983-05-23 |
| 8 | 1991-0m-23 |
| 9 | 19yy-01-23 |
| 10 | y991-01-23 |
| id | birthdate | DOB |
|---|---|---|
| 1 | 1991-01-23 | 1991-01-23 |
| 2 | yyyy-01-23 | null |
| 3 | 1991-mm-23 | null |
| 4 | 1991-01-dd | null |
| 5 | null | |
| 6 | 1991-01-d3 | null |
| 7 | 1983-05-23 | 1983-05-23 |
| 8 | 1991-0m-23 | null |
| 9 | 19yy-01-23 | null |
| 10 | y991-01-23 | null |