DBMS Practice Questions With Answers: MCQs, Short & Long Questions

DBMS Practice Lab

DBMS Practice Questions With Answers: MCQs, Short & Long Questions

Use this page to actively practice Database Management System concepts instead of only reading notes. You get unit-wise DBMS MCQs with instant checking, short-answer questions for 2–5 marks, long-answer questions for 8–10 marks, and focused practice on SQL, normalization, relational algebra, transactions, recovery and concurrency control.

MCQ Practice Progress

0/25 0 answered

MCQ Challenge 25 mixed questions with instant answer checking and short explanations. Start MCQs

Short Answer Drill Practice concise 2-mark and 5-mark answers with expected answer length. Practice Short Answers

Long Answer Writing Room 10-mark questions with answer structure, examiner focus and model points. Practice Long Answers

Need revision before practice?

Use the one-page DBMS revision hub to refresh the complete syllabus first.

Open Complete DBMS Revision Notes

Preparing exam-ready answers?

Use the semester question bank for unit-wise 2, 5 and 10-mark model answers.

Open DBMS Important Questions With Answers

MCQs Short Answers Long Answers Practice Zones Concept Links FAQ

MCQ

Part A: DBMS MCQ Practice Challenge

Select one answer and press Check Answer. Try to answer from memory before opening detailed topic links.

Unit 1: DBMS Basics & Architecture5 MCQs

1

Which statement best describes a DBMS?

Easy

A text editor used to create documents Software used to manage and control data in databases A hardware device used only for backup A programming language used only for web design

2

Which DBMS architecture includes a separate application or business-logic layer?

Easy

1-tier 2-tier 3-tier 0-tier

3

Which term means the overall structure or blueprint of a database?

Easy

Schema Instance Tuple Cursor

4

Changing file organization without changing the logical schema is an example of which concept?

Medium

Entity integrity Logical redundancy View serializability Physical data independence

5

Which language category is mainly used to define database structures?

Easy

DCL DDL TCL DQL only

Unit 2: ER Model, Keys & Relational Model5 MCQs

6

Which key is a minimal super key?

Easy

Foreign key Composite attribute Candidate key Domain

7

What does a tuple represent in the relational model?

Easy

A row A column A data type A database user

8

Which integrity rule says that a primary key cannot be NULL?

Medium

Domain integrity Referential integrity View integrity Entity integrity

9

Which relational algebra operation selects rows that satisfy a condition?

Medium

Projection Selection Rename Division

10

Which relational query approach is non-procedural?

Medium

Relational algebra only Two-phase locking Relational calculus Checkpointing

Unit 3: SQL5 MCQs

11

Which SQL clause filters rows before grouping?

Easy

HAVING WHERE ORDER BY GROUP BY

12

Which SQL function is commonly used to count rows?

Easy

ORDER ALTER GRANT COUNT

13

Which join returns only rows that satisfy the join condition?

Medium

INNER JOIN LEFT JOIN RIGHT JOIN CROSS JOIN

14

Which database object is commonly described as a virtual table?

Easy

Trigger Cursor View Checkpoint

15

Which clause is used to filter grouped results?

Medium

WHERE HAVING SELECT DISTINCT only CREATE

Unit 4: Functional Dependency & Normalization5 MCQs

16

Which normal form focuses on atomic values and removing repeating groups?

Easy

1NF 2NF BCNF 5NF

17

Which normal form removes partial dependency?

Medium

1NF 3NF 4NF 2NF

18

Which normal form is commonly associated with removing transitive dependency?

Medium

1NF 2NF 3NF 4NF

19

In BCNF, what should every determinant of a non-trivial functional dependency be?

Hard

A foreign key only A super key A multivalued attribute A view

20

Which normal form is mainly associated with multivalued dependency?

Medium

1NF 2NF 3NF 4NF

Unit 5: Transactions, Recovery & Concurrency Control5 MCQs

21

Which ACID property means all transaction operations happen or none happen?

Easy

Atomicity Consistency Isolation Durability

22

What does a cycle in a precedence graph indicate?

Hard

The schedule is always serial The schedule is conflict serializable The schedule is not conflict serializable No transaction has written data

23

Which lock is commonly associated with read access?

Easy

Exclusive lock only Shared lock Deadlock Checkpoint lock

24

What happens in the growing phase of two-phase locking?

Medium

Only checkpoints are created All locks are released The transaction must abort Locks are acquired

25

Which concurrency approach maintains multiple versions of data?

Medium

DDL Referential integrity MVCC Projection

SA

Part B: DBMS Short Answer Practice

Try each question yourself first. Then open the model points and compare your answer.

S1Define DBMS and write two advantages.2 Marks

Model Points

A DBMS is software used to create, store, retrieve, update and control data in a database.

• Reduces unnecessary data duplication.
• Improves security, consistency and controlled access.

Expected length: 3–5 lines.

Study Full Concept

S2Differentiate schema and instance.2 Marks

Schema is the database structure or blueprint. Instance is the actual data stored at a particular time. Schema changes less frequently, while instance changes whenever records change.

Expected length: 3–4 lines.

Revise Schema & Instance

S3What is a primary key? How is it different from a foreign key?5 Marks

A primary key uniquely identifies tuples in its own relation. A foreign key references a key in another relation to create a relationship between tables.

Expected length: definition + 3–4 differences + small example.

Revise DBMS Keys

S4What is referential integrity?2 Marks

Referential integrity ensures that a foreign-key value refers to a valid parent-key value or follows the permitted NULL rule.

Expected length: 2–3 lines + one example.

Revise Integrity Constraints

S5Differentiate WHERE and HAVING in SQL.5 Marks

WHERE filters rows before grouping. HAVING is commonly used to filter grouped results after GROUP BY.

Expected length: short definition + 3 differences + example query.

Practice SQL Conditions

S6What is functional dependency?2 Marks

X → Y means the value of X determines the corresponding value of Y. Example: RollNo → StudentName.

Revise Functional Dependency

S7Differentiate 3NF and BCNF.5 Marks

BCNF is generally stricter than 3NF. In BCNF, every determinant of a non-trivial functional dependency must be a super key.

Expected length: definitions + rule + example + conclusion.

Revise 3NF vs BCNF

S8What is a transaction? List the ACID properties.2 Marks

A transaction is a logical unit of database work. ACID stands for Atomicity, Consistency, Isolation and Durability.

Revise Transactions & ACID

S9What is deadlock in DBMS?2 Marks

Deadlock occurs when transactions wait for resources held by one another and none can proceed.

Study Deadlock

S10Explain shared and exclusive locks.5 Marks

A shared lock is commonly used for reading and can be compatible with other shared locks. An exclusive lock is used for writing and blocks conflicting access.

Expected length: definitions + compatibility explanation + example.

Revise Locks & 2PL

LA

Part C: Long Answer Writing Practice

These are writing-room questions. First make your own structure, then compare with the model answer framework.

L1Explain DBMS architecture with 1-tier, 2-tier and 3-tier models.10 Marks

Model Structure

1. Define DBMS architecture.
2. Explain 1-tier with example.
3. Explain 2-tier with client/database-server flow.
4. Explain 3-tier with client/application/database flow.
5. Add a simple diagram and comparison.
6. Conclude with where 3-tier is useful.

Examiner focus: clear architecture flow + diagram + differences.

Study Full Architecture Lesson

L2Explain ER model, mapping constraints, generalization and aggregation.10 Marks

1. Define ER model.
2. Explain entity, attribute and relationship.
3. Show 1:1, 1:M and M:N mapping constraints.
4. Explain generalization and specialization.
5. Explain aggregation.
6. Add a labeled ER example.

Revise ER Model Basics Revise Advanced ER Concepts

L3Explain relational algebra operations with suitable examples.10 Marks

1. Define relational algebra.
2. Explain selection and projection.
3. Explain union and set difference.
4. Explain Cartesian product and rename.
5. Explain join operations.
6. Add one solved expression.

Examiner focus: symbol + meaning + example for each operation.

Practice Relational Algebra

L4Explain SQL joins, subqueries and aggregate functions with examples.10 Marks

1. Define joins and explain common join types.
2. Write one join query.
3. Define subquery with example.
4. Explain COUNT, SUM, AVG, MIN and MAX.
5. Explain GROUP BY and HAVING.

Study SQL Joins & Subqueries

L5Normalize a relation up to 3NF and explain every step.10 Marks

1. Write the original relation.
2. Identify candidate key and functional dependencies.
3. Convert to 1NF by ensuring atomic values.
4. Remove partial dependency for 2NF.
5. Remove transitive dependency for 3NF.
6. Show final decomposed relations.

Examiner focus: dependency reasoning matters more than writing definitions alone.

Revise Normalization Step by Step

L6Explain BCNF, lossless join and dependency preservation.10 Marks

1. Define BCNF.
2. Explain why BCNF is stricter than 3NF.
3. Define decomposition.
4. Explain lossless join.
5. Explain dependency preservation.
6. Add a small decomposition example.

Revise BCNF Revise Lossless Join

L7Explain transactions and ACID properties with a real-life example.10 Marks

1. Define transaction.
2. Use a bank-transfer example.
3. Explain Atomicity.
4. Explain Consistency.
5. Explain Isolation.
6. Explain Durability.
7. Add transaction states if asked.

Revise Transactions & ACID

L8Explain conflict and view serializability.10 Marks

1. Define serial and concurrent schedules.
2. Define conflicting operations.
3. Explain conflict serializability.
4. Show precedence-graph method.
5. Explain view serializability.
6. Compare both concepts.

Examiner focus: schedule analysis + precedence graph.

Practice Serializability

L9Explain database recovery using logs, checkpoints, UNDO and REDO.10 Marks

1. Explain why failures require recovery.
2. Define transaction log.
3. Explain UNDO.
4. Explain REDO.
5. Explain checkpoint.
6. Add a small failure example.

Revise Database Recovery

L10Explain concurrency control using locks, 2PL, timestamp ordering and MVCC.10 Marks

1. Define concurrency control.
2. Explain shared and exclusive locks.
3. Explain two-phase locking.
4. Explain timestamp ordering.
5. Explain validation-based protocol.
6. Explain MVCC.
7. Compare the approaches briefly.

Revise Locks & 2PL Revise Timestamp, Validation & MVCC

LAB

Special DBMS Practice Zones

These are the topics where doing problems is usually more useful than reading definitions repeatedly.

SQL Query Practice

Write a query to find CSE students with marks above 80 and sort them by marks in descending order.

SELECT Name, Marks FROM Student WHERE Department = 'CSE' AND Marks > 80 ORDER BY Marks DESC;

Practice More SELECT Queries

Normalization Practice

Given a relation and its functional dependencies, identify the candidate key first. Then check partial and transitive dependencies before decomposition.

Revise Functional Dependency Practice Normalization

Relational Algebra Practice

For every expression, first identify whether the question is asking you to filter rows, choose columns or combine relations.

Open Solved Relational Algebra Examples

Serializability Practice

List conflicting operations, draw the precedence graph and check whether the graph contains a cycle.

Practice Serializability Schedules

26

Weak Topic? Study the Full DBMS Concept Before Retrying

Use these detailed lessons only when a practice question shows that a particular concept is weak.

What Is DBMS? DBMS vs File System DBMS Architecture Schema, Instance & Data Models Data Independence, Languages & Interfaces ER Model Keys, Mapping Constraints, Generalization & Aggregation Relational Model Integrity Constraints Relational Algebra Relational Calculus SQL Basics SQL SELECT Queries SQL Joins, Subqueries & Aggregates SQL Tables, Views, Indexes, Cursors, Triggers & Procedures Functional Dependency Normalization 1NF, 2NF & 3NF BCNF Lossless Join & Dependency Preservation MVD, 4NF, Join Dependency & 5NF Transactions & ACID Serializability Recoverability & Recovery Deadlock & Distributed Databases Concurrency Control, Locks & 2PL Timestamp, Validation & MVCC

MCQ ScoreTarget: 20+/25 before exam

Short AnswersCan I answer without opening notes?

Long AnswersCan I create a 5-step answer structure?

Weakest UnitRevise it, then retry the practice set.

?

DBMS Practice Questions FAQs

Quick guidance on how to use this practice page effectively.

How many DBMS MCQs should I practice before a semester exam?

There is no fixed number. Use MCQs to check whether you can recall definitions and distinguish similar concepts. If your score is low, revise the weak unit and try a fresh set later.

Should I memorize long DBMS answers?

It is usually better to remember the answer structure, key terms, diagram or example and the main explanation. This makes it easier to adapt the answer to the exact wording of the exam question.

Which DBMS topics need the most written practice?

SQL, relational algebra, normalization, serializability and concurrency-control problems usually benefit from active practice because they involve steps, queries, dependencies or schedules.

Where should I revise the full syllabus before practice?

Use the complete revision hub at DBMS Complete Revision Notes, then return to this page and test yourself.

Where can I find unit-wise important semester questions with model answers?

Use DBMS Important Questions for Semester Exams With Answers for a separate exam-writing focused question bank.