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1. Which of the following is not an example of a database application? a) Banking transactions b) Document databases c) Online gaming d) Airline reservations Answer: c) Online gaming 2. Which problem is associated with storing data in multiple file f...

1. Which of the following is not an example of a database application? a) Banking transactions b) Document databases c) Online gaming d) Airline reservations Answer: c) Online gaming 2. Which problem is associated with storing data in multiple file formats resulting in duplication? a) Data isolation b) Data redundancy and inconsistency c) Security problems d) Integrity problems Answer: b) Data redundancy and inconsistency 3. What is the main purpose of the Data Definition Language (DDL)? a) To access and update data b) To define the database schema c) To ensure transaction atomicity d) To manage concurrent access Answer: b) To define the database schema 4. Which of the following is a characteristic of a relational model? a) Data stored in hierarchical structures b) Data stored in a single flat file c) Data stored in various tables d) Data stored in a network model Answer: c) Data stored in various tables 5. What does the term 'instance' refer to in the context of databases? a) The overall logical structure of the database b) The physical structure of the database c) The actual content of the database at a particular point in time d) The metadata about the database Answer: c) The actual content of the database at a particular point in time 6. What is the primary key in a database? a) A field that uniquely identifies a row in a table b) A field that duplicates information c) A field used for indexing d) A field that contains metadata Answer: a) A field that uniquely identifies a row in a table  7. Which type of DML requires specifying what data are needed without specifying how to get those data? a) Procedural DML b) Declarative DML c) Structured DML d) Hierarchical DML Answer: b) Declarative DML 8. Which SQL clause is used to filter records in a query? a) SELECT b) FROM c) WHERE d) ORDER BY Answer: c) WHERE 9. Which of the following is a function of the storage manager in a database system? a) Interpreting DDL statements b) Efficient storing, retrieving, and updating of data c) Query optimization d) Transaction processing Answer: b) Efficient storing, retrieving, and updating of data 10. In a three-tier architecture, where does the application server reside? a) Client machine b) Database system c) Middle layer d) Front end Answer: c) Middle layer 11. Who are naive users in the context of database systems? a) Users who write application programs b) Users who interact with the system using a query language c) Users who interact through predefined application programs d) Users who write specialized database applications Answer: c) Users who interact through predefined application programs 12. Which component ensures the consistency of the database during concurrent transactions? a) Query processor b) Storage manager c) Transaction management component d) Data dictionary Answer: c) Transaction management component  13. What is physical data independence? a) The ability to modify the logical schema without changing the physical schema b) The ability to modify the physical schema without changing the logical schema c) The ability to store data in multiple formats d) The ability to access data using different languages Answer: b) The ability to modify the physical schema without changing the logical schema 14. Which database architecture is characterized by a single server machine executing work on behalf of multiple client machines? a) Centralized databases b) Client-server c) Parallel databases d) Distributed databases Answer: b) Client-server 15. Which era saw the emergence of SQL as an industrial standard? a) 1950s and early 1960s b) Late 1960s and 1970s c) 1980s d) 1990s Answer: c) 1980s 16. What is the main function of a database administrator (DBA)? a) Writing application programs b) Query optimization c) Managing the database schema and storage structure d) Performing routine maintenance on operating systems Answer: c) Managing the database schema and storage structure 17. What is a characteristic of NoSQL systems? a) They use relational models b) They are designed for big data storage c) They support SQL queries exclusively d) They are used for small-scale applications Answer: b) They are designed for big data storage 18. Which component translates DML statements into low-level instructions? a) DDL interpreter b) DML compiler c) Query evaluation engine d) Storage manager Answer: b) DML compiler  19. Which database application example involves managing production, inventory, orders, and supply chain? a) Enterprise Information b) Manufacturing c) Banking and finance d) Universities Answer: b) Manufacturing 20. What is the term for a collection of operations that performs a single logical function in a database application? a) Query b) Transaction c) Schema d) Instance Answer: b) Transaction - True/False Questions with Explanations 1. Data redundancy and inconsistency occur when data is stored in multiple file formats. True Explanation: When data is stored in multiple formats, it can lead to data being duplicated and inconsistent across different files, causing redundancy and inconsistency issues. 2. Declarative DMLs are harder to learn and use compared to procedural DMLs. False Explanation: Declarative DMLs are generally easier to learn and use because they focus on what data is required rather than how to retrieve it, making them more user-friendly. 3. The logical schema of a database refers to its physical structure. False Explanation: The logical schema defines the logical structure of the database, such as tables, views, and indexes, while the physical schema deals with how the data is actually stored. 4. The relational model stores data in hierarchical structures. False Explanation: The relational model stores data in tables (relations), not hierarchical structures. Hierarchical structures are used in hierarchical databases. 5. A primary key is a field that uniquely identifies a row in a table. True Explanation: A primary key is used to uniquely identify each record in a table, ensuring that no two rows have the same primary key value. 6. SQL is a Turing machine equivalent language. False Explanation: SQL is a declarative language used for querying databases and is not equivalent to a Turing machine, which is a theoretical model of computation. 7. In a two-tier architecture, the client machine acts as a front end with no direct database calls. False Explanation: In a two-tier architecture, the client machine interacts directly with the database, making direct database calls. 8. Naive users are unsophisticated users who interact with the system using predefined application programs. True Explanation: Naive users typically use the database system through predefined application programs without needing to understand the underlying database structure or query languages. 9. Transaction management ensures that the database remains in a consistent state despite failures. True Explanation: Transaction management ensures that all database transactions are processed reliably and that the database remains consistent, even in the event of a failure. 10. The term 'instance' refers to the actual content of the database at a particular point in time. True Explanation: An instance is the snapshot of the data stored in the database at a specific moment in time. 11. Physical data independence allows modifying the physical schema without changing the logical schema. True Explanation: Physical data independence refers to the ability to change the physical storage of the data without affecting the logical schema. 12. A DDL compiler translates DML statements into evaluation plans. False Explanation: A DDL compiler interprets data definition language (DDL) statements to create the database schema, not data manipulation language (DML) statements. 13. In a three-tier architecture, the application server communicates directly with the database system. True Explanation: In a three-tier architecture, the application server (middle tier) handles business logic and communicates directly with the database server (back end) to retrieve and manipulate data. 14. Parallel databases involve many core shared memory or shared disk systems. True Explanation: Parallel databases are designed to improve performance by using multiple processors and storage devices in a shared memory or shared disk configuration. 15. The storage manager is responsible for query optimization. False Explanation: The query processor, not the storage manager, is responsible for query optimization. The storage manager handles the storage, retrieval, and updating of data. 16. SQL was developed in the 1990s. False Explanation: SQL was developed in the 1970s by IBM researchers and became an industrial standard in the 1980s. 17. A database index provides fast access to data items holding particular values. True Explanation: Indexes are used to quickly locate and access data without having to search every row in a database table. 18. The query processor includes components like the DDL interpreter and the query evaluation engine. True Explanation: The query processor consists of various components, including the DDL interpreter for schema definitions and the query evaluation engine for executing queries. 19. The database administrator is responsible for periodically backing up the database. True Explanation: One of the key responsibilities of a database administrator (DBA) is to ensure that the database is backed up regularly to prevent data loss. 20. Object-oriented database systems became prominent in the 1950s. False Explanation: Object-oriented database systems became prominent in the 1980s and 1990s, not the 1950s. The 1950s were the era of early computer systems and simpler data storage models like hierarchical and network databases.