Database Management Systems – Multiple Choice Questions (MCQs)

1. 13. What is a database schema?

   • A. The logical structure of the database
   • B. The physical storage of the database
   • C. The data stored in the database
   • D. The users who access the database

2. 14. What is data integrity?

   • A. The accuracy and consistency of data
   • B. The speed of data retrieval
   • C. The security of data
   • D. The size of the database

3. 15. What are constraints in a database?

   • A. Rules that enforce data integrity
   • B. Queries used to retrieve data
   • C. Ways to organize tables
   • D. Methods for backup and recovery

4. 16. Which of the following is a type of constraint?

   • A. NOT NULL
   • B. UNIQUE
   • C. PRIMARY KEY
   • D. FOREIGN KEY

5. 17. What is normalization?

   • A. The process of organizing data in a database to reduce redundancy and improve data integrity
   • B. The process of making the database faster
   • C. The process of securing the database
   • D. The process of backing up the database

6. 18. What is 1NF (First Normal Form)?

   • A. A table where each cell contains a single value
   • B. A table with a primary key
   • C. A table with no repeating groups
   • D. A table with no transitive dependencies

7. 19. What is 2NF (Second Normal Form)?

   • A. A table in 1NF with no partial dependencies
   • B. A table with a primary key and no repeating groups
   • C. A table in 1NF with no transitive dependencies
   • D. A table with all non-key attributes fully functionally dependent on the primary key

8. 20. What is 3NF (Third Normal Form)?

   • A. A table in 2NF with no transitive dependencies
   • B. A table in 2NF with no repeating groups
   • C. A table in 2NF where all non-key attributes are directly dependent on the primary key
   • D. A table with a primary key and no partial dependencies

9. 21. What is BCNF (Boyce-Codd Normal Form)?

   • A. A stronger form of 3NF where every determinant is a candidate key
   • B. A table in 3NF with no multi-valued dependencies
   • C. A table in 3NF with a composite primary key
   • D. A table in 3NF with only one candidate key

10. 22. What is a database query?

    • A. A request for data from a database
    • B. A command to create a table
    • C. A rule to enforce data integrity
    • D. A method for backing up data

11. 23. What does SQL stand for?

    • A. Structured Query Language
    • B. Simple Query Language
    • C. System Query Language
    • D. Standard Query Logic

12. 24. Which SQL command is used to retrieve data from a database?

    • A. SELECT
    • B. INSERT
    • C. UPDATE
    • D. DELETE