SQL MCQ Questions and Answers for Practice

1. Which SQL statement is used to update a database table schema?

1. UPDATE TABLE
2. MODIFY TABLE
3. ALTER TABLE
4. CHANGE TABLE

2. Database normalisation typically

1. Reduces number of tables
2. Reduces database size
3. Reduces data constraints
4. None of the above

3. A SQL database view

1. Contains data not stored in the database tables
2. Is computed using a SQL query
3. Takes up more disk space whenever more data is added to the database
4. Is a way to improve the read time of a table in a database

4. Which of the following are SQL aggregate functions?

1. MIN
2. Insert
3. SELECT
4. JOIN

5. In a typical master/slave database system

1. Reads can be made on the slave and Writes can be made on the slave
2. Reads can be made on the slave and Writes can be made on the master
3. Reads can be made on the master and Writes can be made on the master
4. Reads can be made on the master and Writes can be made on the slave

6. A database index

1. Increases database size
2. Decreases database size
3. Doesn’t affect database size
4. Impacts database size differently in different cases

7. Which of the following will help when a database begins to become too large to keep on one system

1. Setting up a slave database
2. Sharding database and Archiving data
3. Archiving data Only
4. Setting up daily database dump

8. Which of the following code will create an index named stu_sub_ind on the columns roll_num and subject of the student_subjects table?

1. create index stu_sub_ind from student_subjects(roll_num, subject);
2. create index stu_sub_ind on student_subjects(roll_num, subject);
3. create index stu_sub_ind (roll_num, subject) on student_subjects;
4. It’s not possible to create an index on two columns