CS3492 Database Management Systems Previous Year Question Papers - Anna University

UNIT I: Relational Databases

Part A (2 Marks)

• Define Data Abstraction and its three levels.
• What is the difference between DDL and DML?
• Distinguish between a Primary Key, Candidate Key, and Super Key.
• What is a "Relational Schema" and "Relational Instance"?
• Define Referential Integrity.

Part B (13 Marks)

• Explain the Database System Architecture with a neat block diagram.
• Discuss the various Relational Algebra operations (Selection, Projection, Join, Division) with examples.
• Explain the structure of SQL Queries including Nested Subqueries and Aggregate Functions.

UNIT II: Database Design

Part A (2 Marks)

• What is a Weak Entity Set? How is it represented in an ER diagram?
• Define Functional Dependency.
• What is the purpose of Normalization?
• List the anomalies that occur if a database is not normalized.
• Compare 3NF and BCNF.

Part B (13 Marks)

• Design an ER Diagram for a specific scenario (e.g., University, Library, or Hospital) and convert it into tables.
• Explain 1NF, 2NF, and 3NF with suitable examples and decomposition rules.
• Discuss the Dependency Preservation and Lossless Join properties in database design.

UNIT III: Transactions

Part A (2 Marks)

• State the ACID properties of a transaction.
• What is a "Schedule" in DBMS? Define a Serial Schedule.
• Define Deadlock and list its four necessary conditions.
• What is the difference between a "Shadow Paging" and "Log-based Recovery"?

Part B (13 Marks)

• Explain Conflict Serializability and how to test for it using a precedence graph.
• Discuss the Two-Phase Locking (2PL) protocol and its variations (Strict, Rigorous).
• Describe the ARIES Recovery Algorithm in detail (Analysis, Redo, and Undo phases).

UNIT IV: Implementation Techniques

Part A (2 Marks)

• What is the main difference between Static and Dynamic Hashing?
• Define Query Optimization.
• What is a "Dense Index" vs. a "Sparse Index"?
• List the different levels of RAID.

Part B (13 Marks)

• Explain the structure and operations of B+ Tree Indexing with an example.
• Describe the steps involved in Query Processing (Parsing, Optimization, Evaluation).
• Discuss RAID levels (0, 1, 5, 6, 10) and their trade-offs in performance and reliability.

UNIT V: Advanced Topics

Part A (2 Marks)

• What are the characteristics of NoSQL databases?
• Explain the CAP Theorem.
• What is a Distributed Database?
• Define SQL Injection and how it can be prevented.

Part B (13 Marks)

• Explain the Distributed Data Storage techniques (Replication and Fragmentation).
• Discuss the different types of NoSQL databases (Key-Value, Document, Columnar, Graph).
• Describe Access Control mechanisms (Discretionary vs. Mandatory Access Control).

Most Repeated / High-Weight Questions

ER diagrams and normalization (Unit II), ACID properties and transactions (Unit III), B+ tree indexing and query processing (Unit IV), deadlock detection and recovery algorithms.