AG/CSIT(CI)/IT-405 (GS) – Data Base Management System

B.Tech./B.Tech. (Working Professional), IV Semester
Examination, December 2025
Grading System (GS) / Working Professional
Max Marks: 70 | Time: 3 Hours

Note:
i) Attempt any five questions.
ii) All questions carry equal marks.
iii) Assume any missing data.

Previous Year Questions (December 2025)

Q.1

a) Differentiate between File System and DBMS. Discuss the advantages of a database system over a file-based system. (Unit 1)

b) Draw and explain an E-R diagram for a University database system. Consider entities like students, courses and faculty. (Unit 1)
Q.2

a) Explain the concept of weak entity sets. How do generalization, specialization and aggregation extend the E-R model. (Unit 2)

b) Consider the following relational schema:
Student(Roll_no, Name, Dept, Year, Marks)
write relational algebra queries to:
i) Retrieve names of students in the CS department
ii) Find students who scored more than 80 marks (Unit 2)
Q.3

a) Compare sorting, join and selection operations in query processing. (Unit 3)

b) Why is query optimization necessary in large databases? Discuss with an example. Explain the measures of query cost. (Unit 3)
Q.4

a) Discuss the types of anomalies that arise in an un-normalized database. Explain how normalization helps to eliminate these anomalies. (Unit 4)

b) Consider the following relation.
Employee (Emp_ID, Name, Dept, Salary, Project_ID, Project_Name, Manager_ID)
i) Identify functional dependencies
ii) Convert it to 3NF and BCNF. (Unit 4)
Q.5

a) Define a transaction in a database. Explain the ACID properties of transactions with examples. (Unit 5)

b) Why is concurrency control important in database systems? Discuss the impact of concurrency control on transaction performance. (Unit 5)
Q.6

a) What is data independence? Explain logical and physical data independence with an example. (Unit 1)

b) How does relational algebra help in database query processing? Explain with an example. (Unit 2)
Q.7

a) Explain the importance of decomposition in database design. What is lossless and dependency-preserving decomposition? (Unit 4)

b) What is deadlock in a database? Explain deadlock prevention and deadlock detection mechanisms. (Unit 5)
Q.8

Write short notes on (any two)

a) Two-Phase Locking (2PL) protocol (Unit 5)

b) Distributed databases: Concepts and Challenges (Unit 5)

c) Serializability in transactions (Unit 5)

d) Multi-valued dependency (Unit 4)