Answered step by step
Verified Expert Solution
Link Copied!

Question

1 Approved Answer

Read the following scenario and address the following issues that are related to transaction and concurrency control. Assume that objects a1, a2, and a3 are

Read the following scenario and address the following issues that are related to transaction and concurrency control.

Assume that objects a1, a2, and a3 are managed by a server, which provides two operations to operate the objects.

read(a): returns the value of object a

write(a, v): assigns the value v to object a

Assume that the following two concurrent transactions T and U are performed on these objects

T: read(a2); read(a1); write(a2, a2-25); read(a3); write(a1, a1+52)

U: read(a3); read(a2); write(a2, a2+33); write(a3, a3-26)

Assume that the original values of a1, a2, and a3 are 111, 106 and 125 respectively. Answer the following questions based on the above scenario.

question (1) - If there is no concurrency control, transactions T and U may perform the following interleaving operations on objects a1, a2 and a3. What problem can be caused by the operations? Justify your answer.

--> When the above requirement in question (1) is satisfied, what would be the correct values of a1, a2 and a3 after T and U commit?

Step by Step Solution

There are 3 Steps involved in it

Step: 1

blur-text-image

Get Instant Access to Expert-Tailored Solutions

See step-by-step solutions with expert insights and AI powered tools for academic success

Step: 2

blur-text-image_2

Step: 3

blur-text-image_3

Ace Your Homework with AI

Get the answers you need in no time with our AI-driven, step-by-step assistance

Get Started

Recommended Textbook for

Graph Databases

Authors: Ian Robinson, Jim Webber, Emil Eifrem

1st Edition

1449356265, 978-1449356262

More Books

Students also viewed these Databases questions

Question

=+9. Think about a campaign direction.

Answered: 1 week ago