SQL Online Quiz

Q 1 - Which of the following is not true about SQL statements?

A - SQL statements are not case sensitive.

B - SQL statements can be written on one or more lines.

C - Keywords cannot be split across lines.

D - Clauses must be written on separate lines.

Q 2 - Which of the following is not a character manipulation function?

A - concat

B - substr

C - instr

D - coalesce

Q 3 - Which of the following is not true about Natural Joins?

A - Natural join is based on all columns in two tables having same name

B - It selects rows from the two tables having different values in the matched columns.

C - If columns having same names have different data types, it returns error.

D - None of the above.

Q 4 - 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 ON clause

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

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

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

D - None of the above.

Q 5 - Which of the following query will result in an error?

A - select dept_id, avg(salary) from employees group by dept_id;

B - select avg(salary) from employees group by dept_id;

C - select dept_id, job_id, avg(salary) from employees group by dept_id, job_id;

D - select dept_id, count(name) from employees;

Q 6 - Which of the following comparison operators could be used in a multiple row query?

A - IN operator

B - ANY operator

C - ALL operator

D - All of the above

Q 7 - Which of the following is not true about the database objects?

A - Indexes improve performance of queries.

B - Views give alternative names to objects.

C - Sequences are numeric value generators.

D - Tables are the basic unit of storage.

Q 8 - Which of the following is true about deleting a table from the database?

A - All the data in the table are deleted

B - The table structure is removed

C - The indexes in the table are deleted

D - All of the above.

Q 9 - Which of the following is not true about the Pseudocolumns that return the sequence values?

A - NEXTVAL returns the next available sequence value.

B - CURRVAL gets the current sequence value.

C - PREVVAL gets the previous sequence value.

D - None of the above.

Q 10 - Which of the following statements allows William to change his database user account password to bill?

A - create user william identified by bill;

B - alter user william identified by bill

C - create user william password bill;

D - alter user william password bill;