SQL topshirig‘i 7.6 darajasi
Quyidagi jadval berilgan:
| id | name | grade |
|---|---|---|
| 1 | John | 91 |
| 2 | Alex | 92 |
| 3 | Evans | 72 |
| 4 | Alisa | 85 |
| 5 | Donella | 66 |
| 6 | Lauren | 79 |
| 7 | Matthew | 56 |
| 8 | Andrew | 62 |
| 9 | Richard | 55 |
| 10 | Sam | 50 |
Uning uchun quyidagi masalalarni yeching:
O‘rtacha balldan yuqori ball olgan talabalarning o‘rtacha ballini toping.
90 balldan yuqori bahosi bo‘lmagan talabalarning sonini toping.
