[QUIZ] Test your understanding of SQL - Part 7

Part 7 of the SQL quiz goes into the SQL practice exercises that follow the previous period.

Question 1: What is the result of the following SQL statement?
```
 SELECT COUNT(DISTINCT STUDENT_ID) FROM EXAM_RESULTS; 
```
1. 3
2. 4
3. 5
4. 6
Question 2: Which SQL statement is used to calculate the average test score for the 1st test?
1. SELECT AVG (DIEM_KT) FROM KETQUA_KIEMTRA;
2. SELECT AVG (DIEM_KT) FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 1;
3. SELECT AVG (DIEM_KT) FROM KETQUA_KIEMTRA GROUP BY ID_BAIKT;
4. SELECT COUNT (DIEM_KT) FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 1;
Question 3: Which SQL statement is used to calculate each test how many students have done?
1. SELECT COUNT (DISTINCT ID_SV) FROM KETQUA_KIEMTRA GROUP BY ID_BAIKT;
2. SELECT ID_BAIKT, MAX (ID_SV) FROM KETQUA_KIEMTRA GROUP BY ID_BAIKT;
3. SELECT ID_BAIKT, COUNT (DISTINCT ID_SV) FROM KETQUA_KIEMTRA GROUP BY ID_BAIKT;
4. SELECT ID_BAIKT, MIN (ID_SV) FROM KETQUA_KIEMTRA GROUP BY ID_BAIKT;
Question 4: Which SQL statement is used to print out the record of all students who start with 'L'?
1. SELECT * FROM KETQUA_KIEMTRA WHERE HO_SV LIKE 'L%';
2. SELECT * FROM KETQUA_KIEMTRA WHERE HO_SV LIKE 'L';
3. SELECT * FROM KETQUA_KIEMTRA WHERE HO_SV = 'L';
4. SELECT * FROM KETQUA_KIEMTRA WHERE HO_SV <> 'L';

Question 5: What is the result of the following SQL statement?

 SELECT MAX(DIEM_KT) FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 1 AND HO_SV LIKE '%U%';

Question 6: Which SQL statement is used to print out the records of all students whose first or last name ends with 'N'?
1. SELECT * FROM KETQUA_KIEMTRA WHERE TEN_SV LIKE '% N' OR HO_SV LIKE '% N';
2. SELECT * FROM KETQUA_KIEMTRA WHERE TEN_SV LIKE 'N' OR HO_SV LIKE 'N';
3. SELECT * FROM KETQUA_KIEMTRA WHERE TEN_SV LIKE 'N%' OR HO_SV LIKE 'N%';
4. SELECT * FROM KETQUA_KIEMTRA WHERE TEN_SV LIKE '% N%' OR HO_SV LIKE '% N%';
Question 7: Which SQL statement is used to find the names of all students who score higher than 90 on the 2nd test?
1. SELECT TEN_SV, HO_SV FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 2 OR DIEM_KT> 90;
2. SELECT TEN_SV, HO_SV FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 2 AND DIEM_KT> 90;
3. SELECT TEN_SV, HO_SV FROM KETQUA_KIEMTRA WHERE DIEM_KT> 90;
4. SELECT TEN_SV, HO_SV FROM KETQUA_KIEMTRA WHERE ID_BAIKT = 2 HAVING DIEM_KT> 90;
Question 8: Which SQL statement is used to find the names of all students who scored a total of 2 tests higher than 180?
1. SELECT TEN_SV, HO_SV, SUM (DIEM_KT) FROM KETQUA_KIEMTRA GROUP BY TEN_SV, HO_SV;
2. SELECT TEN_SV, HO_SV, SUM (DIEM_KT) FROM KETQUA_KIEMTRA HAVING SUM (DIEM_KT)> 180;
3. SELECT TEN_SV, HO_SV, SUM (DIEM_KT) FROM KETQUA_KIEMTRA GROUP BY TEN_SV, HO_SV HAVING SUM (DIEM_KT)> 180;
4. SELECT TEN_SV, HO_SV, SUM (DIEM_KT) FROM KETQUA_KIEMTRA WHERE DIEM_KT> 180 GROUP BY TEN_SV, HO_SV;
Question 9: How many records have the following SQL statement generated?
```
 SELECT * FROM KETQUA_KIEMTRA WHERE HO_SV LIKE '%U%' AND DIEM_KT > 75; 
```
1. 3
2. 4
3. 5
4. There is no answer
Question 10: How many records do the following SQL statements return?
```
 SELECT * FROM KETQUA_KIEMTRA WHERE ID_SV <= 12 AND DIEM > 85; 
```
1. 5
2. 4
3. 3
4. 2