NSCT – Distributed Databases MCQs 20 min Score: 0 Attempted: 0/20 Subscribe 1. . A distributed database is: (A) A single central database (B) A database in which data is stored across multiple physical locations connected via a network (C) A compressed backup (D) An encrypted fileShow All Answers 2. . Main goals of a distributed database include: (A) Encryption only (B) Compression only (C) Transparency, reliability, and efficiency (D) Deleting old data automatically 3. . Data fragmentation in distributed databases is: (A) Deleting old records (B) Encrypting tables (C) Compressing tables (D) Dividing a database into smaller pieces called fragments 4. . Horizontal fragmentation means: (A) Compressing rows (B) Dividing a table into subsets of columns (C) Encrypting rows (D) Dividing a table into subsets of rows 5. . Vertical fragmentation means: (A) Dividing a table into subsets of rows (B) Dividing a table into subsets of columns (C) Encrypting columns (D) Compressing columns 6. . Replication in distributed databases refers to: (A) Encrypting tables (B) Storing copies of data at multiple sites for reliability and availability (C) Compressing tables (D) Deleting old records 7. . Data allocation refers to: (A) Deleting old data (B) Compressing tables (C) Encrypting tables (D) Assigning fragments of data to specific sites in a distributed system 8. . Advantages of distributed databases include: (A) Improved reliability, availability, performance, and scalability (B) Compressed data only (C) Encrypted data only (D) Automatic deletion of old records 9. . Disadvantages of distributed databases include: (A) Complex design, high cost, and network dependency (B) Only encryption issues (C) Only compression issues (D) Automatic deletion issues 10. . Transparency in distributed databases includes: (A) Compression transparency only (B) Encryption transparency only (C) Location, replication, fragmentation, and concurrency transparency (D) Backup transparency only 11. . Location transparency means: (A) Data is encrypted (B) Users do not need to know the physical location of data (C) Data is compressed (D) Data is deleted automatically 12. . Replication transparency means: (A) Data is backed up (B) Data is compressed (C) Data is encrypted (D) Users are unaware of multiple copies of data 13. . Fragmentation transparency means: (A) Data is compressed (B) Users can access data without knowing how it is fragmented (C) Data is encrypted (D) Data is deleted automatically 14. . Concurrency control in distributed databases ensures: (A) Encryption of data (B) Compression of data (C) Correct execution of concurrent transactions across multiple sites (D) Backup of data only 15. . Distributed deadlock occurs when: (A) Backups fail (B) Tables are compressed (C) Data is encrypted (D) Transactions at different sites wait indefinitely for resources held by each other 16. . Two-phase commit protocol in distributed databases is used to: (A) Ensure all sites agree to commit a transaction or abort it (B) Compress tables (C) Encrypt tables (D) Delete old records 17. . Global query optimization in distributed databases aims to: (A) Compress data (B) Minimize overall query execution cost across all sites (C) Encrypt data (D) Delete old records 18. . Advantages of replication include: (A) Encryption only (B) Compression only (C) Increased reliability and faster local access (D) Automatic deletion 19. . Challenges of distributed databases include: (A) Network delays, consistency maintenance, deadlocks, and recovery (B) Only compression issues (C) Only encryption issues (D) Backup issues only 20. . The main purpose of distributed databases is to: (A) Encrypt data (B) Compress data (C) Provide efficient, reliable, and transparent access to data across multiple sites (D) Delete old records automatically
