This quiz works best with JavaScript enabled. Home > Class 12 > Class 12 Computer Science Chapter 3 Database Management Systems – Quiz 45 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Computer Science Chapter 3 Database Management Systems Quiz 45 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. What is required for converting a strong entity set with only simple attributes into a relational model? A) One table with attributes of the entity set. B) Two tables with primary keys. C) A composite attribute table. D) A multi-valued attribute table. Show Answer Correct Answer: A) One table with attributes of the entity set. 2. What are mapping constraints in an ER model? A) Mapping constraints specify the number of instances of one entity that can be associated with instances of another entity in an ER model. B) Mapping constraints determine the color and size of entities in a diagram. C) Mapping constraints are used to create relationships between tables in SQL. D) Mapping constraints define the attributes of an entity. Show Answer Correct Answer: A) Mapping constraints specify the number of instances of one entity that can be associated with instances of another entity in an ER model. 3. While practicing object oriented programming using Java, the execution of every Java program is under the control of: A) Java Virtual Machine (JVM). B) Java Virtual class (JVC). C) Java application. D) Java applet. Show Answer Correct Answer: A) Java Virtual Machine (JVM). 4. Describe the concept of foreign keys in relational databases. A) Foreign keys are used to link tables in relational databases, ensuring data integrity and establishing relationships between them. B) Foreign keys are used to store large amounts of data in a single table. C) Foreign keys are primarily for indexing data to improve query performance. D) Foreign keys are a type of data type used in programming languages. Show Answer Correct Answer: A) Foreign keys are used to link tables in relational databases, ensuring data integrity and establishing relationships between them. 5. What is the main benefit of using a database management system in healthcare? A) Allows manual entry of patient data. B) Provides a structured way to store and retrieve patient information efficiently. C) Automatically diagnoses patients without human intervention. D) Replaces the need for healthcare professionals. Show Answer Correct Answer: B) Provides a structured way to store and retrieve patient information efficiently. 6. Given a table students with columns student ..... id, name, and major, which SQL query lists all students majoring in 'Computer Science'? A) SELECT * FROM students WHERE major = 'Computer Science';. B) SELECT name FROM students WHERE major = 'Computer Science';. C) SELECT student id, name FROM students WHERE major = 'Computer Science';. D) SELECT student id FROM students WHERE major = 'Computer Science';. Show Answer Correct Answer: C) SELECT student id, name FROM students WHERE major = 'Computer Science';. 7. Define the term 'table' in the context of a database. A) A table is a graphical representation of data without any structure. B) A table is a structured collection of data in rows and columns in a database. C) A table is a single row of data in a database. D) A table is a type of software used for managing databases. Show Answer Correct Answer: B) A table is a structured collection of data in rows and columns in a database. 8. Which of the following is an advantage of the database approach? A) Reduced structural dependence. B) Increased data redundancy. C) Limited data sharing. D) Increased program maintenance. Show Answer Correct Answer: A) Reduced structural dependence. 9. What is the main advantage of using a NoSQL database? A) Relational data structure. B) Strict data consistency. C) Scalability and flexibility. D) Support for complex transactions. Show Answer Correct Answer: C) Scalability and flexibility. 10. MongoDB is an example of a relational database. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 11. What type of join includes all tuples from both participating relations? A) Full Outer Join. B) Right Outer Join. C) Left Outer Join. D) Inner Join. Show Answer Correct Answer: A) Full Outer Join. 12. ..... :Manages data policies and standards. A) Data Administrator (DA). B) Database User. C) System Analyst. D) Network Administrator. Show Answer Correct Answer: A) Data Administrator (DA). 13. ..... :Storing copies of data at multiple sites. A) Data Replication. B) Data Encryption. C) Data Compression. D) Data Fragmentation. Show Answer Correct Answer: A) Data Replication. 14. What do backups and replication protect against? A) Server upgrades. B) User errors. C) File format changes. D) Data loss. Show Answer Correct Answer: D) Data loss. 15. What does ACID stand for in database transactions? A) Accuracy, Clarity, Integrity, Stability. B) Atomicity, Clarity, Isolation, Reliability. C) Atomicity, Consistency, Isolation, Durability. D) Atomicity, Consistency, Isolation, Accessibility. Show Answer Correct Answer: C) Atomicity, Consistency, Isolation, Durability. 16. Which type of database is mentioned under "Database Architectures & Major Types of Databases" ? A) Operational Databases. B) Relational Algebra. C) Quantum Databases. D) Blockchain Databases. Show Answer Correct Answer: A) Operational Databases. 17. What does normalization help to improve? A) Data integrity. B) Data color. C) Data duplication. D) Data confusion. Show Answer Correct Answer: A) Data integrity. 18. What is the primary purpose of key constraints in relational databases? A) To link tables together. B) To ensure only valid data is entered into tables. C) To increase processing speed. D) To duplicate data for backup purposes. Show Answer Correct Answer: B) To ensure only valid data is entered into tables. 19. How can foreign keys help maintain data integrity? A) Foreign keys allow duplicate entries in a table. B) Foreign keys help maintain data integrity by ensuring that relationships between tables are valid and that referenced data exists. C) Foreign keys are only relevant for primary keys in a single table. D) Foreign keys can be used to delete all data in a database. Show Answer Correct Answer: B) Foreign keys help maintain data integrity by ensuring that relationships between tables are valid and that referenced data exists. 20. What is the reason for not accepting zero in the fields of Access tables? A) Fields is set with is Null or > 0. B) Fields is set with is Null or < = 0. C) Fields is set with is Null or! [0]. D) Fields is set with is Null or like "?". Show Answer Correct Answer: A) Fields is set with is Null or > 0. 21. What kind of data does Netflix's database primarily manage? A) Financial transactions. B) User preferences for recommendations. C) Hospital records. D) School attendance data. Show Answer Correct Answer: B) User preferences for recommendations. 22. In ordered indices the file containing the records is sequentially ordered, a ..... is an index whose search key also defines the sequential order of the file. A) Clustered index. B) Structured index. C) Unstructured index. D) Nonclustered index. Show Answer Correct Answer: A) Clustered index. 23. What is Big Data? A) Data that is always accurate. B) Data that is easy to manage. C) A collection of data that is too large and complex for traditional systems. D) Data that is only stored in one location. Show Answer Correct Answer: C) A collection of data that is too large and complex for traditional systems. 24. What is the result of a set difference operation? A) No records. B) All records combined. C) Records in both relations. D) Records in one relation only. Show Answer Correct Answer: D) Records in one relation only. 25. The attribute refers to a ..... of a table A) Record. B) Foreign key. C) Primary key. D) Field. Show Answer Correct Answer: D) Field. ← PreviousNext →Related QuizzesClass 12 Computer Science Chapter 3 Database Management Systems Quiz 1Class 12 Computer Science Chapter 3 Database Management Systems Quiz 2Class 12 Computer Science Chapter 3 Database Management Systems Quiz 3Class 12 Computer Science Chapter 3 Database Management Systems Quiz 4Class 12 Computer Science Chapter 3 Database Management Systems Quiz 5Class 12 Computer Science Chapter 3 Database Management Systems Quiz 6Class 12 Computer Science Chapter 3 Database Management Systems Quiz 7Class 12 Computer Science Chapter 3 Database Management Systems Quiz 8Class 12 Computer Science Chapter 3 Database Management Systems Quiz 9Class 12 Computer Science Chapter 3 Database Management Systems Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books