Data Base Management System (IT-405) - Important Questions

Explain the three-level schema architecture of a database system and the need for mappings between schema levels.

Differentiate between file system and DBMS and describe the disadvantages of file system / advantages of DBMS over file-based system.

Draw and explain an Entity-Relationship (E-R) diagram for a database application (e.g., University with students, courses and faculty).

Discuss relational algebra fundamental operators with suitable examples.

Consider relational schema Student(Roll_no, Name, Dept, Year, Marks). Write relational algebra queries to retrieve names of CS department students and students scoring more than 80 marks.

Explain foreign key and referential integrity constraints with suitable example using Department and Employee tables.

Explain SQL data definition and data manipulation statements with suitable examples.

Why is query optimization necessary in large databases? Discuss with an example. Explain the measures of query cost.

Explain trivial and non-trivial functional dependencies with suitable examples.

Given a relation and functional dependencies, determine the highest normal form and normalize it to 3NF and BCNF.

Explain relational database decomposition, its importance and process, including lossless and dependency-preserving decomposition with suitable examples.

Explain Fourth Normal Form (4NF) and Fifth Normal Form (5NF) with suitable examples.

Define a transaction and explain the ACID properties (Atomicity, Consistency, Isolation, Durability) with examples.

Discuss concurrency control and locking-free concurrency control with suitable examples.

What is deadlock in a database? Explain deadlock prevention and deadlock detection mechanisms.

Write short notes on distributed databases and object-oriented database systems.