Bsc CSIT Semester 4 – Database Management System – Unit 9: Concurrency Control Techniques (4 Hrs.)

Question 1

What is concurrency control? Name various methods of controlling the concurrency control? Differentiate between Binary lock and shared/Exclusive lock.

Marks: 10

Year: 2076 Final TU

Concurrency Control Concurrency Control refers to the techniques used in a DBMS to ensure that multiple users or transactions can access the database at the same time without causing data inconsistenc

Question 2

What is Granularity of data items? How does it effect in concurrency control?

Marks: 5

Year: 2076 Final TU

Granularity of Data Items Granularity in DBMS refers to the size or level of data items on which a transaction can lock data for concurrency control. - It determines how much data is locked at a tim

Question 3

Explain 2 phase locking technique in brief.

Marks: 5

Year: 2076 Final TU

Two-Phase Locking (2PL) Technique Two-Phase Locking (2PL) is a concurrency control method used in DBMS to ensure serializability of transactions. It works by controlling how locks are acquired and r

Question 4

Explain deadlock and starvation. Explain Time stamp based protocol for concurrency control?

Marks: 10

Year: 2078 Final TU

1. Deadlock Deadlock is a situation in DBMS where two or more transactions are waiting for each other to release resources, and none of them can proceed further. It occurs when transactions form a c

Question 5

What is concurrency control? What are its advantages in DBMS?

Marks: 5

Year: 2079 Final TU

1. Definition Concurrency Control in DBMS is a technique used to manage simultaneous operations on the database without conflicting with each other. - It ensures that multiple transactions can execu

Question 6

What is two-phase locking? What are different types of locks in two-phase locking? Explain basic, conservative, strict, rigorous two-phase locking. What is lock conversion?

Marks: 10

Year: 2080 Final TU

1. Definition of Two-Phase Locking (2PL) Two-Phase Locking (2PL) is a concurrency control protocol used in DBMS to ensure serializability of transactions. - It ensures that no two conflicting operat

Question 7

Why do we need concurrency control in databses? Explain.

Marks: 5

Year: 2080 Final TU

1. Definition Concurrency control is a technique used in DBMS to manage simultaneous execution of multiple transactions while preserving data consistency and integrity. - It ensures that transaction

Question 8

Explain deadlock with example. What are different deadlock prevention protocols? Explain deadlock detection and starvation.

Marks: 10

Year: 2080 Final TU

1. Deadlock Definition: A deadlock occurs when two or more transactions in a database system wait indefinitely for resources held by each other, preventing any of them from proceeding. Conditions fo

Question 9

How timestamp ordering protocol is used for ensuring concurrency control?

Marks: 5

Year: 2080 Final TU

Timestamp Ordering Protocol for Concurrency Control 1. Definition Timestamp Ordering (TO) Protocol is a non-locking concurrency control method that ensures serializability of transactions using times

Question 10

Explain transaction deadlock with example.

Marks: 5

Year: 2081 Final TU

Transaction Deadlock in DBMS A deadlock in a database occurs when two or more transactions wait for each other to release resources, and none of them can proceed. It usually happens when transaction