SQL Online Quiz

Q 1 - Consider the following schema −

STUDENTS(student_code, first_name, last_name, email, 
         phone_no, date_of_birth, honours_subject, percentage_of_marks);

Which of the following query would display the full name of a student, with a column heading "Name"

A - select first_name, last_name as “Name” from students;

B - select Name from students;

C - select first_name || last_name as “Name” from students;

D - select first_name, last_name from students;

Q 2 - Consider the following schema −

STUDENTS(student_code, first_name, last_name, email, 
         phone_no, date_of_birth, honours_subject, percentage_of_marks);

Which of the following query would display names and percentage of marks of all students sorted by honours subject, and then order by percentage of marks?

A - select first_name, last name, honours_subject, percentage_of_marks from students order by honours_subject, percentage_of_marks;

B - select first_name, last name, honours_subject, percentage_of_marks order by percentage_of_marks desc from students;

C - select first_name, last name, percentage_of_marks from students order by percentage_of_marks desc;

D - select first_name, last name, percentage_of_marks from students order by percentage_of_marks, honours_subject;

Q 3 - Consider the following schema −

HONOURS_SUBJECT(subject_code, subject_name, department_head);

LOCATIONS(subject_code, department_name, location_id, city);

Select the right query for retrieving records from the tables HONOURS_SUBJECT and LOCATIONS with the USING clause

A - select h.subject_name, l.department_name, h.department_head, l.city from honours_subject h join location l using(subject_code);

B - select h.subject_name, l.department_name, h.department_head, l.city from honours_subject h natural join location l using(subject_code);

C - select h.subject_name, l.department_name, h.department_head, l.city from honours_subject h, location l using(subject_code);

D - None of the above.

Q 4 - Which of the following is not true about the ON clause?

A - ON clause is used to specify conditions or specify columns to join.

B - ON clause makes the query easy to understand.

C - ON clause does not allow three way joins.

D - None of the above.

Q 5 - Which of the following is not true about the COUNT function?

A - COUNT(*) returns the number of rows in the table.

B - COUNT(exp) returns the number of rows with non-null values for the exp.

C - COUNT(DISTINCT exp) returns the number of unique, non-null values in the column.

D - All are true.

Q 6 - Which of the following is true about inserting news rows to a table?

A - You must list values in the default order of the columns in the table.

B - You can also list the columns in the INSERT clause.

C - You can use the INSERT statement to add rows from one table to another.

D - All of the above.

Q 7 - Which of the following is NOT true about the SQL transaction control statements?

A - The COMMIT statement ends the current transaction and makes all data changes permanent.

B - The ROLLBACK statement ends the transaction and discards all the pending data changes.

C - Each DML statement is automatically committed.

D - All are true.

Q 8 - Which of the following is not true about simple views?

A - They derive data from one table.

B - They contain no functions or grouping.

C - You cannot perform DML operations through a simple view.

D - All of the above are true.

Q 9 - Which of the following code will delete a view named all_marks_english?

A - delete view all_marks_english;

B - drop view all_marks_english;

C - delete all_marks_english;

D - drop all_marks_english;

Q 10 - Which of the following code would create a role named student_admin?

A - CREATE student_admin;

B - GRANT student_admin;

C - CREATE ROLE student_admin;

D - ROLE student_admin;