By using db<>fiddle, you agree to license everything you submit by Creative Commons CC0.
| P | Q | R |
|---|---|---|
| 1 | A | 甲 |
| 2 | A | 丙 |
| 3 | D | 甲 |
| 4 | C | 丙 |
| 5 | X | 乙 |
| 6 | A | 甲 |
| 7 | D | 甲 |
| 8 | C | 乙 |
| 9 | X | 甲 |
| 10 | D | null |
| 11 | C | 乙 |
| 12 | C | 乙 |
| Q | R | M | PERCENT |
|---|---|---|---|
| A | 甲 | 2 | 40% |
| D | 甲 | 2 | 40% |
| X | 甲 | 1 | 20% |
| C | 乙 | 3 | 75% |
| X | 乙 | 1 | 25% |
| A | 丙 | 1 | 50% |
| C | 丙 | 1 | 50% |