By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
SELECT 11
| a | b | c | cnt |
|---|---|---|---|
| 1 | 1 | null | 4 |
| 2 | null | null | null |
| 3 | null | null | null |
| 4 | null | 1 | null |
| 6 | null | null | null |
| 7 | null | null | null |
| 8 | 1 | null | 2 |
| 9 | null | 1 | null |
| 10 | 1 | null | 2 |
| 11 | null | 1 | null |
| 12 | 1 | 1 | 1 |
SELECT 11