This quiz works best with JavaScript enabled. Home > Cbse > Class 12 > Science > Computer Science > Class 12 Computer Science Chapter 3 Database Management Systems – Quiz 15 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 12 Computer Science Chapter 3 Database Management Systems Quiz 15 (60 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Which component of a DBMS is responsible for converting user queries into instructions the database can execute? A) Query processor. B) Data dictionary. C) Backup manager. D) Report generator. Show Answer Correct Answer: A) Query processor. 2. List the types of data models commonly used in DBMS. A) Flat File. B) Columnar. C) Hierarchical, Network, Relational, Object-Oriented, Document. D) Key-Value. Show Answer Correct Answer: C) Hierarchical, Network, Relational, Object-Oriented, Document. 3. A database is in BCNF but still has redundancy. What could be the possible reason? A) It still contains transitive dependencies. B) It has overlapping candidate keys. C) It lacks a foreign key constraint. D) It does not have a primary key. Show Answer Correct Answer: B) It has overlapping candidate keys. 4. Define normalization and its importance in database design. A) Normalization is the process of combining all data into a single table. B) Normalization is only necessary for large databases. C) Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity. D) Normalization increases data redundancy and decreases performance. Show Answer Correct Answer: C) Normalization is the process of organizing data in a database to reduce redundancy and improve data integrity. 5. What is the main function of the query processor? A) To ensure data security. B) To create user interfaces. C) To manage data storage. D) To interpret and execute database queries. Show Answer Correct Answer: D) To interpret and execute database queries. 6. How can ER diagrams be extended to include more complex relationships? A) ER diagrams cannot include attributes for entities. B) ER diagrams can include weak entities, ternary relationships, and generalization/specialization. C) ER diagrams are limited to one-to-one relationships only. D) ER diagrams can only represent binary relationships. Show Answer Correct Answer: B) ER diagrams can include weak entities, ternary relationships, and generalization/specialization. 7. Which key uniquely identifies a record? A) Foreign key. B) Primary key. C) Candidate key. D) Composite key. Show Answer Correct Answer: B) Primary key. 8. The internetworked organizational databases at different sites to be integrated and synchronized with all the facilities of database approach is ..... A) Centralized database. B) Globalized database. C) Distributed database. D) Localized database. Show Answer Correct Answer: C) Distributed database. 9. What is the purpose of a data model? A) To create visual representations of data only. B) To store data without any structure. C) To eliminate the need for data analysis. D) The purpose of a data model is to represent and organize data in a structured way to support data management and analysis. Show Answer Correct Answer: D) The purpose of a data model is to represent and organize data in a structured way to support data management and analysis. 10. What does a primary key do? A) Allows duplicates. B) Identifies records uniquely. C) Stores data. D) Links tables. Show Answer Correct Answer: B) Identifies records uniquely. 11. What are the limitations of a file-based approach? A) No recovery, inefficient, no simultaneous access, separation and isolation, duplication, data dependence, fixed queries. B) Allows for efficient retrieval, insertion, update, and management of data. C) Provides information necessary for managing organisations effectively. D) Handles the daily transactions of an organisation. Show Answer Correct Answer: A) No recovery, inefficient, no simultaneous access, separation and isolation, duplication, data dependence, fixed queries. 12. The third step in the data modeling process with a packaged data model is: A) Rename relationships. B) Interview users. C) Rename identified data elements. D) Map data to be used from package to data in current databases. Show Answer Correct Answer: D) Map data to be used from package to data in current databases. 13. Generalization is a top-down process. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 14. What is the purpose of CRUD operations? A) To manipulate data. B) To write stories. C) To play games. D) To create art. Show Answer Correct Answer: A) To manipulate data. 15. When considering database selection, which factor is NOT typically important? A) User interface design. B) Volume of data. C) Type of queries. D) Data storage requirements. Show Answer Correct Answer: A) User interface design. 16. Insertion of a large number of entries at a time into an index is referred to as ..... of the index. A) Bulk loading. B) Bulk insertion. C) Increase insertion. D) Loading. Show Answer Correct Answer: A) Bulk loading. 17. In the hierarchical model, how is data organized? A) As an inverted tree. B) In a graph. C) In two-dimensional tables. D) None of the above. Show Answer Correct Answer: A) As an inverted tree. 18. What is a multi-valued attribute in a relational schema? A) An attribute that cannot be NULL. B) An attribute that references another table. C) An attribute that is unique for each tuple. D) An attribute that can have multiple values. Show Answer Correct Answer: D) An attribute that can have multiple values. 19. Which mode of transmission sender act as sender and act as receiver after some time interval? A) Unidirectional. B) Full duplex. C) Simplex. D) Half duplex. Show Answer Correct Answer: D) Half duplex. 20. What is the primary purpose of the ER Model? A) To optimize database performance through indexing. B) To store data in a flat file format. C) To ensure data security and privacy. D) To visually represent data structure and relationships in a database. Show Answer Correct Answer: D) To visually represent data structure and relationships in a database. 21. Deadlock:When two transactions wait for each other's locks and cannot ..... A) Communicate. B) Commit. C) Proceed. D) Rollback. Show Answer Correct Answer: C) Proceed. 22. Describe a recovery algorithm used in database management. A) Shadow Paging. B) Two-Phase Commit Protocol. C) Write-Ahead Logging (WAL) protocol. D) Database Replication Method. Show Answer Correct Answer: C) Write-Ahead Logging (WAL) protocol. 23. Which database concept ensures that relationships between tables remain valid? A) Data redundancy. B) Logical schema. C) Referential integrity. D) Query processing. Show Answer Correct Answer: C) Referential integrity. 24. How does a DBMS handle data transformation and presentation? A) By translating logical requests into commands to physically locate and retrieve the requested data. B) By compressing data for storage. C) By generating random data for testing. D) By deleting obsolete data automatically. Show Answer Correct Answer: A) By translating logical requests into commands to physically locate and retrieve the requested data. 25. What is the main difference between SQL and NoSQL databases? A) SQL databases are unstructured. B) NoSQL databases support complex queries. C) NoSQL databases are always faster. D) SQL databases use a fixed schema. Show Answer Correct Answer: D) SQL databases use a fixed schema. 26. Processed data, or ..... , can be used as the basis for decision making. A) DP. B) Raw data. C) Information. D) Queries. Show Answer Correct Answer: C) Information. 27. Explain the use of the WHERE clause in SQL queries. A) The WHERE clause is used to join multiple tables in SQL queries. B) The WHERE clause is used to aggregate data in SQL queries. C) The WHERE clause is used to sort records in SQL queries. D) The WHERE clause is used to filter records in SQL queries based on specified conditions. Show Answer Correct Answer: D) The WHERE clause is used to filter records in SQL queries based on specified conditions. 28. What level of data and process distribution describes a system where all processing and data storage occur on a single computer? A) DPMS. B) MPMD. C) SPSD. D) MPSD. Show Answer Correct Answer: C) SPSD. 29. In a crop yield database, which field should ideally serve as the primary key? A) Crop Type. B) Farmer Name. C) Farm ID or Crop ID. D) Yield Value. Show Answer Correct Answer: C) Farm ID or Crop ID. 30. What is an additional cost that may arise from using a DBMS? A) Purchase of more storage space. B) No impact on hardware performance. C) Decreased need for additional hardware. D) Reduced storage space requirements. Show Answer Correct Answer: A) Purchase of more storage space. 31. Which property ensures that database transactions maintain a consistent state? A) Atomicity. B) Durability. C) Consistency. D) Isolation. Show Answer Correct Answer: C) Consistency. 32. What is a benefit of using a DBMS? A) They create automatic backups. B) They provide seamless Internet access to database data. C) They provide full security to data using private/public key encryption. D) They help create an environment for end users to have access to more data. Show Answer Correct Answer: A) They create automatic backups. 33. In an ERD, what does cardinality specify? A) The attributes of an entity. B) The foreign keys of a table. C) The primary keys of a table. D) The number of instances of an entity related to another entity. Show Answer Correct Answer: D) The number of instances of an entity related to another entity. 34. What is the purpose of the UNIQUE constraint? A) To create a backup. B) To link multiple tables. C) To ensure all values are different. D) To allow duplicate values. Show Answer Correct Answer: C) To ensure all values are different. 35. Which of the following ensures only authorized users can access specific data in a DBMS? A) User authentication and access rights. B) Data redundancy. C) Normalization. D) Logical schema. Show Answer Correct Answer: A) User authentication and access rights. 36. What is a disadvantage of the database approach related to performance? A) Greater impact of a failure. B) Improved backup and recovery services. C) Balanced conflicting requirements. D) Increased data consistency. Show Answer Correct Answer: A) Greater impact of a failure. 37. What is the significance of backup and recovery in DBMS? A) Backup and recovery are essential for data protection, integrity, and availability in a DBMS. B) Backup processes slow down database performance significantly. C) Recovery is only needed in case of hardware failure. D) Backup and recovery are only necessary for large databases. Show Answer Correct Answer: A) Backup and recovery are essential for data protection, integrity, and availability in a DBMS. 38. Which DBMS does Facebook use to store and access vast amounts of user data? A) MySQL. B) Oracle Database. C) SQLite. D) MongoDB. Show Answer Correct Answer: A) MySQL. 39. What are the common techniques for SQL query optimization? A) Common techniques for SQL query optimization include using indexes, rewriting queries, avoiding SELECT *, using appropriate JOINs, and analyzing execution plans. B) Ignoring database statistics. C) Using only aggregate functions. D) Relying solely on subqueries. Show Answer Correct Answer: A) Common techniques for SQL query optimization include using indexes, rewriting queries, avoiding SELECT *, using appropriate JOINs, and analyzing execution plans. 40. In a relational schema, what is a foreign key? A) A key that uniquely identifies a record in a table. B) A key that is used for encryption. C) A reference to a primary key in another table. D) A key that allows null values. Show Answer Correct Answer: C) A reference to a primary key in another table. 41. Which of the following is a common use of SQL? A) Creating web pages. B) Managing user interfaces. C) Querying databases. D) Designing graphics. Show Answer Correct Answer: C) Querying databases. 42. What is a key advantage of using a database management system in a hospital setting? A) It provides a centralized and organized way to store patient information. B) It eliminates the need for healthcare professionals. C) It automatically diagnoses patients without human intervention. D) It allows for manual entry of patient data. Show Answer Correct Answer: A) It provides a centralized and organized way to store patient information. 43. Name a popular database management tool. A) SQLite. B) MongoDB. C) MySQL. D) PostgreSQL. Show Answer Correct Answer: C) MySQL. 44. Which function does a distributed DBMS perform? A) Does not support different DBMSs at different nodes. B) Only manages local databases. C) Keeps track of data locations in a distributed data dictionary. D) Requires manual data retrieval by users. Show Answer Correct Answer: C) Keeps track of data locations in a distributed data dictionary. 45. Purpose of Backup:To restore data after ..... failure. A) Disk. B) Monitor. C) Printer. D) Network. Show Answer Correct Answer: A) Disk. 46. Which DBMS does Amadeus use for managing travel booking data? A) Redis. B) MariaDB. C) Snowflake. D) Couchbase. Show Answer Correct Answer: D) Couchbase. 47. These are the details or characteristics of an entity A) Attribute. B) Cardinal. C) All the above. D) None of the above. Show Answer Correct Answer: A) Attribute. 48. Which of the following is not a level of data abstraction? A) Physical Level. B) View Level. C) Critical Level. D) Logical Level. Show Answer Correct Answer: C) Critical Level. 49. Serializable Schedule:A non-serial schedule that produces the same result as a ..... schedule. A) Serial. B) Parallel. C) Random. D) Deadlock. Show Answer Correct Answer: A) Serial. 50. What is the purpose of a rollback in transaction management? A) To create a backup of the transaction data. B) To enhance the performance of a transaction. C) To revert changes made during a transaction in case of an error. D) To permanently save changes made during a transaction. Show Answer Correct Answer: C) To revert changes made during a transaction in case of an error. 51. What is the purpose of the UPDATE statement in SQL? A) To retrieve data from a table. B) To modify existing records in a table. C) To create a new record in a table. D) To delete records from a table. Show Answer Correct Answer: B) To modify existing records in a table. 52. What is the purpose of the DELETE statement in SQL? A) To update existing rows in a table. B) To create a new table in the database. C) To remove rows from a table in a database. D) To retrieve data from a table. Show Answer Correct Answer: C) To remove rows from a table in a database. 53. Identify a major component of the DBMS environment. A) User Interface. B) Data Warehouse. C) Network Protocol. D) Database Engine. Show Answer Correct Answer: D) Database Engine. 54. Which of the following is an example of a relational database management system? A) Redis. B) Oracle. C) Neo4j. D) MongoDB. Show Answer Correct Answer: B) Oracle. 55. Which query is used for sorting data that retrieves all the fields from empinfo table and listed them in the ascending order? A) SELECT * FROM empinfo ORDER BY COLUMN age;. B) SELECT * FROM empinfo ORDER age;. C) SELECT * FROM empinfo ORDER BY age;. D) SELECT * FROM empinfo SORT BY age;. Show Answer Correct Answer: C) SELECT * FROM empinfo ORDER BY age;. 56. A company is experiencing frequent upgrade and replacement cycles with their DBMS. What strategic action could they take to minimize disruption? A) Develop a long-term upgrade plan and schedule regular maintenance. B) Ignore upgrades and continue using outdated software. C) Switch to manual record keeping. D) Rely solely on vendor recommendations without internal planning. Show Answer Correct Answer: A) Develop a long-term upgrade plan and schedule regular maintenance. 57. When normalizing a database, what is the main goal of transforming it into the Third Normal Form (3NF)? A) To ensure data is atomic. B) To remove transitive dependencies. C) To reduce the number of tables. D) To increase data redundancy. Show Answer Correct Answer: B) To remove transitive dependencies. 58. A subtype can become a supertype if the subtype has other subtypes beneath it. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: A) True. 59. All of the following are steps to using a packaged data model EXCEPT: A) Identify the parts of the data model that apply to your data modeling situation. B) Utilize all business rules that come with the packaged data model. C) Rename the identified data elements. D) Map data to be used in packages with existing data in the current databases. Show Answer Correct Answer: B) Utilize all business rules that come with the packaged data model. 60. What is the significance of data independence for database users? A) Data independence prevents users from modifying the database structure. B) Data independence is significant as it enables changes to the database schema without impacting application programs. C) Data independence is crucial for ensuring data is always encrypted. D) Data independence allows users to access data without any restrictions. Show Answer Correct Answer: B) Data independence is significant as it enables changes to the database schema without impacting application programs. ← 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 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 8 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books