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

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

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.

Describe the functions and responsibilities of the Database Administrator (DBA).

Explain entities, attributes, entity types and relationships.

What is data independence? Explain logical and physical data independence with an example.

Explain how the data is organized in a network DBMS? How it is different from Hierarchical DBMS.

Explain the components of DBMS with a neat diagram

Define and explain levels of data abstraction, instances, schema, and physical and logical data independence

Explain the relational data model with domains and relations.

Discuss relational algebra operators with suitable examples.

Explain weak entity sets and how generalization, specialization and aggregation extend the E-R model.

Write relational algebra queries to retrieve names of CS department students and students scoring more than 80 marks from Student schema.

Explain how relational algebra helps in database query processing with an example.

Explain foreign key and referential integrity constraints

What is the impact of weak entity set in database design? Discuss with an example.

Develop an Entity Relationship diagram for Indian movies. It should include where it was shot, details of the actors, directors, producers, the movie language and so on.

Compute results of projection over natural join and left outer join on given relations R1 and R2.

Differentiate specialization and generalization with the help of an example.

Explain in detail about various key constraints used in database system.

Give SQL and relational algebra expressions to find patients assigned to more than one doctor and doctors treating Polio patients.

Explain SQL data definition and data manipulation statements.

Discuss views, query processing and compare the features of ORACLE.

Compare sorting, join and selection operations in query processing.

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

Give an example of two relations giving a meaningful full outer join and formulate the full outer join in SQL.

Write SQL queries on employee and department tables for filtering, updating, aggregation and subqueries.

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

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

Explain trivial and non-trivial functional dependencies.

Explain normalization up to BCNF with dependency preservation.

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

Discuss types of anomalies in an un-normalized database and how normalization eliminates them.

Normalize a given unnormalized employee table with multi-valued attributes to the possible extent.

Write short note on any two: a) Multi Valued Dependency b) Expression Evaluation Plan c) Object Oriented Data Base System.

State the Armstrong inference rules. Provide suitable examples to describe each.

Define normalization and explain 2NF, 3NF and BCNF with suitable example.

Given a set of FDs $$A \rightarrow B, ABCD \rightarrow E, EF \rightarrow G$$ Is $ACDF \rightarrow G$ implied by the set of given FDs? Justify your answer.

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

Discuss concurrency control and locking-free concurrency control.

Explain database protection and security mechanisms.

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

Write short notes on Two-Phase Locking protocol, distributed databases concepts and challenges, serializability in transactions, and multi-valued dependency.

Why is concurrency control important in database systems and what is its impact on transaction performance?

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

Write short notes on any two of: Oracle APEX, Database Anomalies, Distributed Databases, Views.

Determine whether a given schedule is conflict serializable.

Create a concurrent schedule for two given transactions and calculate the final values of the data items.

Explain with an example when concurrent execution of two transactions leads to conflict.

Illustrate the two-phase locking (2PL) protocol and its variants with an example.