This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Computer Science > Class 12 Computer Science Chapter 3 Database Management Systems – Quiz 5 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Computer Science Chapter 3 Database Management Systems Quiz 5 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which of the following is a feature of a semi-structured data model? A) Allows different sets of attributes for the same data type. B) Uses only relational structures. C) Is not used in modern applications. D) Requires fixed schemas. Show Answer Correct Answer: A) Allows different sets of attributes for the same data type. 2. What type of attribute cannot be divided further? A) Simple. B) Multi-value. C) Composite. D) Derived. Show Answer Correct Answer: A) Simple. 3. Data ..... helps help people use information to make decisions and take actions. A) Checks. B) Integrity. C) Validation. D) Accuracy. Show Answer Correct Answer: B) Integrity. 4. What are the three levels of data abstraction in a DBMS? A) Data level, schema level, and user level. B) Physical level, conceptual level, and external level. C) The three levels of data abstraction in a DBMS are physical level, logical level, and view level. D) Storage level, logical level, and interface level. Show Answer Correct Answer: C) The three levels of data abstraction in a DBMS are physical level, logical level, and view level. 5. What is a composite key and how is it used in normalization? A) A composite key is a single column used to identify records. B) Normalization eliminates the need for any keys in a database. C) A composite key is used only for indexing and has no role in normalization. D) A composite key is a unique identifier made up of multiple columns, used in normalization to ensure unique records and reduce redundancy. Show Answer Correct Answer: D) A composite key is a unique identifier made up of multiple columns, used in normalization to ensure unique records and reduce redundancy. 6. What is a natural way to perform ad hoc queries? A) Using CSV files. B) Using SQL or filters. C) Using manual scanning. D) Using spreadsheets. Show Answer Correct Answer: B) Using SQL or filters. 7. A NULL value represents: A) Empty String. B) 0. C) Error. D) Unknown or Unavailable Data. Show Answer Correct Answer: D) Unknown or Unavailable Data. 8. A relational database management system (RDBMS) is ideal for handling large volumes of unstructured data. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 9. What is a relationship? A) Two relational databases share a field. B) When two people have the same surname. C) When two or more people have the same surname. D) When a database has two matching primary keys. Show Answer Correct Answer: A) Two relational databases share a field. 10. Explain the concept of subqueries in SQL. A) A subquery is a method to create new tables in SQL. B) A subquery is a command to delete records from a table. C) A subquery is a type of database index. D) A subquery is a nested query that provides results to the enclosing query. Show Answer Correct Answer: D) A subquery is a nested query that provides results to the enclosing query. 11. Which of the following is a feature of a relational database? A) Hierarchical data storage. B) Network data model. C) Tables with rows and columns. D) Object-oriented data model. Show Answer Correct Answer: C) Tables with rows and columns. 12. Why are naming conventions not standardized across different companies? A) Because all companies use the same software systems. B) Because different companies in the same field have different naming conventions. C) Because naming conventions are legally protected. D) Because naming conventions are irrelevant in modern databases. Show Answer Correct Answer: B) Because different companies in the same field have different naming conventions. 13. Airbnb uses which DBMS to ensure scalability and ease of management? A) IBM Db2. B) Google Cloud Spanner. C) Amazon RDS. D) Microsoft Access. Show Answer Correct Answer: C) Amazon RDS. 14. In 1-tier architecture, all of the following are on the same machine EXCEPT: A) Application Logic. B) Database. C) Server Machine. D) Client Interface. Show Answer Correct Answer: C) Server Machine. 15. If a process of operating system is ready to execute, but waiting for availability of resources, then the possible state in this process could be identified as ..... A) Waiting State. B) Exit State. C) Ready State. D) New Born State. Show Answer Correct Answer: C) Ready State. 16. What is a data dictionary in a DBMS? A) A collection of metadata describing the structure of the database. B) A user manual for database users. C) A backup of all database records. D) A software tool for managing indexes. Show Answer Correct Answer: A) A collection of metadata describing the structure of the database. 17. Exclusive Lock (X Lock):Allows only one transaction to ..... and ..... a data item. A) Update, delete. B) Read, delete. C) Write, delete. D) Read, write. Show Answer Correct Answer: D) Read, write. 18. What is a characteristic of a relational database? A) Data cannot be related. B) Data is stored in tables. C) Data is unstructured. D) Data is stored in key-value pairs. Show Answer Correct Answer: B) Data is stored in tables. 19. What are access rights in a DBMS? A) Permissions granted to users to perform specific operations on a database. B) The physical location where a database is stored. C) The process of converting data into a structured format. D) The rules and guidelines for data entry and manipulation. Show Answer Correct Answer: A) Permissions granted to users to perform specific operations on a database. 20. Which type of query in MS Access is used to summarize data and calculate averages or totals? A) Crosstab Query. B) Parameter Query. C) Update Query. D) Select Query. Show Answer Correct Answer: A) Crosstab Query. 21. Explain the concept of data integrity. A) Data integrity is the process of deleting unnecessary data. B) Data integrity is the ability to store data in multiple formats. C) Data integrity refers to the speed of data processing. D) Data integrity is the maintenance of, and the assurance of, the accuracy and consistency of data over its entire lifecycle. Show Answer Correct Answer: D) Data integrity is the maintenance of, and the assurance of, the accuracy and consistency of data over its entire lifecycle. 22. Which operation is NOT part of data manipulation in a database? A) Update. B) Backup. C) Deletion. D) Insertion. Show Answer Correct Answer: B) Backup. 23. The process of structuring data to reduce redundancy is called: A) Transformation. B) Aggregation. C) Optimization. D) Normalization. Show Answer Correct Answer: D) Normalization. 24. Which DBMS is used by NASA for analyzing complex data relationships? A) Neo4j. B) Couchbase. C) Redis. D) InfluxDB. Show Answer Correct Answer: A) Neo4j. 25. Identify the spatial data type that is used to represent a continuous surface, such as temperature or elevation? A) Point. B) Raster. C) Polygon. D) LineString. Show Answer Correct Answer: B) Raster. 26. In the relational model, a row is also known as a: A) Field. B) Tuple. C) Key. D) Attribute. Show Answer Correct Answer: B) Tuple. 27. What is a Database Management System (DBMS)? A) Software for managing databases B) A type of hardware C) A programming language D) A network protocol A) A cloud storage service. B) A web browser. C) A type of operating system. D) A) Software for managing databases. Show Answer Correct Answer: D) A) Software for managing databases. 28. Which database language is used for defining and manipulating the structure of the database? A) Python. B) Java. C) C++. D) SQL. Show Answer Correct Answer: D) SQL. 29. Why is encapsulation important in object-oriented programming? A) It hides implementation details and only exposes necessary data through methods. B) It allows methods from different classes to be accessed directly. C) It prevents the use of multiple classes in a single program. D) It forces all classes to have only public variables. Show Answer Correct Answer: A) It hides implementation details and only exposes necessary data through methods. 30. What does 'data independence' mean? A) Applications are insulated from how data is structured. B) Data can be accessed by anyone. C) Data is stored in multiple locations. D) Data is always encrypted. Show Answer Correct Answer: A) Applications are insulated from how data is structured. 31. Which of the following describes a one-to-many relationship? A) One entity is associated with one entity. B) One entity is associated with multiple entities. C) Multiple entities are associated with one entity. D) No entities are associated. Show Answer Correct Answer: B) One entity is associated with multiple entities. 32. In a remote transaction, each SQL statement can reference data from multiple remote sites. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 33. How does indexing improve database performance? A) Indexing slows down data retrieval by adding extra steps. B) Indexing increases the amount of data stored in the database. C) Indexing has no effect on search time or performance. D) Indexing enhances database performance by speeding up data retrieval and reducing search time. Show Answer Correct Answer: D) Indexing enhances database performance by speeding up data retrieval and reducing search time. 34. Dirty Read (Uncommitted Dependency):Reading data written by a transaction that has not ..... A) Rolled back. B) Committed. C) Locked. D) Executed. Show Answer Correct Answer: B) Committed. 35. Define metadata? A) Recorded facts. B) Interrelated data. C) Software that manages and control data. D) Data that describes other data. Show Answer Correct Answer: D) Data that describes other data. 36. Name three types of DBMS. A) Multidimensional DBMS. B) Distributed DBMS. C) Object-oriented DBMS. D) Hierarchical DBMS, Network DBMS, Relational DBMS. Show Answer Correct Answer: D) Hierarchical DBMS, Network DBMS, Relational DBMS. 37. What type of data independence is the ability to modify the physical or internal schema without changing the logical or external schemas? A) Physical Data Independence. B) Logical Data Independence. C) All the above. D) None of the above. Show Answer Correct Answer: A) Physical Data Independence. 38. Explain the concept of a data dictionary in a DBMS. A) A data dictionary only contains user data without any metadata. B) A data dictionary is a type of database management software. C) A data dictionary is a repository of metadata that describes the structure, relationships, and constraints of data in a database. D) A data dictionary is used solely for data backup purposes. Show Answer Correct Answer: C) A data dictionary is a repository of metadata that describes the structure, relationships, and constraints of data in a database. 39. What does SQL stand for in database management systems? A) Structured Query Language. B) Simple Query Language. C) Sequential Query Language. D) Standard Query Language. Show Answer Correct Answer: A) Structured Query Language. 40. Describe the ACID properties of transactions. A) ACID properties:Atomicity, Consistency, Isolation, Durability. B) Accuracy, Clarity, Integrity, Reliability. C) Atomicity, Concurrency, Isolation, Stability. D) Atomicity, Consistency, Isolation, Availability. Show Answer Correct Answer: A) ACID properties:Atomicity, Consistency, Isolation, Durability. 41. Rollback:Undoing changes made by ..... transactions. A) Failed. B) Committed. C) Active. D) Uncommitted. Show Answer Correct Answer: D) Uncommitted. 42. What are the primary responsibilities of a Database Administrator (DBA)? A) The primary responsibilities of a Database Administrator (DBA) include database management, performance tuning, backup and recovery, security management, and policy implementation. B) Data entry and customer support. C) Network administration and hardware maintenance. D) Software development and coding. Show Answer Correct Answer: A) The primary responsibilities of a Database Administrator (DBA) include database management, performance tuning, backup and recovery, security management, and policy implementation. 43. The disjoint rule specifies that if an entity instance of the supertype is a member of one subtype, it MUST simultaneously be a member of another subtype. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 44. A company is experiencing frequent errors due to inconsistent data across departments. Which of the following DBMS advantages would best address this issue? A) Minimized data inconsistency. B) Increased end-user productivity. C) Improved decision making. D) Improved data sharing. Show Answer Correct Answer: A) Minimized data inconsistency. 45. Which of the following best describes the challenge of "Maintaining Currency" in DBMS? A) Keeping the DBMS updated with the latest technology and standards. B) Ensuring the database is free from errors. C) Reducing the cost of database management. D) Increasing vendor independence. Show Answer Correct Answer: A) Keeping the DBMS updated with the latest technology and standards. 46. If a database system frequently experiences deadlocks, which of the following would be the best approach to handle the issue? A) Implementing deadlock detection and resolution. B) Removing all foreign key constraints. C) Avoiding the use of ACID properties. D) Increasing the database cache size. Show Answer Correct Answer: A) Implementing deadlock detection and resolution. 47. An entity instance of a subtype represents the same entity instance of the supertype. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 48. In an ER diagram, a relationship set is represented by: A) A rectangle. B) A line. C) A diamond. D) An ellipse. Show Answer Correct Answer: C) A diamond. 49. One of the major challenges in data modeling is to recognize and clearly represent entities that are almost the same. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 50. What is a factor contributing to the cost of DBMSs? A) Fixed cost regardless of usage. B) Variability based on functionality and environment. C) Low initial purchase price. D) Free annual maintenance services. Show Answer Correct Answer: B) Variability based on functionality and environment. 51. ..... :Dividing data across multiple sites. A) Data Compression. B) Data Encryption. C) Data Partitioning. D) Data Replication. Show Answer Correct Answer: C) Data Partitioning. 52. Which architecture is designed to promote data independence in a DBMS? A) Three-tier architecture. B) Two-tier architecture. C) Single-tier architecture. D) Multi-tier architecture. Show Answer Correct Answer: A) Three-tier architecture. 53. Which of the following best describes the term 'Normalization' in databases? A) A process of reducing redundancy in a database. B) A method of encrypting database records. C) A way to back up database files. D) A technique for speeding up query execution. Show Answer Correct Answer: A) A process of reducing redundancy in a database. 54. In a distributed database architecture, what is the main benefit of replicating databases to various sites and interconnecting them via a network? A) Improved database performance and security. B) Reduced number of users. C) Increased vulnerability to failure. D) Limited data sharing. Show Answer Correct Answer: A) Improved database performance and security. 55. What is the function of the LIMIT clause in SQL? A) To restrict the number of records returned. B) To filter records. C) To sort the results. D) To group records. Show Answer Correct Answer: A) To restrict the number of records returned. 56. What does a binary relationship with cardinality ratio 1:1 indicate? A) One to many. B) One to one. C) Many to many. D) Many to one. Show Answer Correct Answer: B) One to one. 57. Which of the following is an example of a many-to-many relationship? A) Students and classes. B) Employees and departments. C) Customers and orders. D) Authors and books. Show Answer Correct Answer: A) Students and classes. 58. Which of the following is a NoSQL database? A) MongoDB. B) MySQL. C) SQLite. D) PostgreSQL. Show Answer Correct Answer: A) MongoDB. 59. How do Codd's rules ensure data integrity in a database? A) Codd's rules allow unstructured data storage. B) Codd's rules focus solely on user interface design. C) Codd's rules eliminate the need for primary keys. D) Codd's rules ensure data integrity by enforcing structured data representation, primary keys, and foreign key relationships. Show Answer Correct Answer: D) Codd's rules ensure data integrity by enforcing structured data representation, primary keys, and foreign key relationships. 60. Which type of database supports data located at a single site? A) Centralized. B) Distributed. C) Hierarchical. D) Relational. Show Answer Correct Answer: A) Centralized. ← PreviousNext →Related QuizzesScience QuizzesClass 12 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 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 9 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books