Given the system logs in the table below that shows the operations of four transactions T1, T2, T3 and T4. a) What is the purpose of using checkpoint? b) In case of recovery using deferred update, which transactions will be undone? which transactions will be redone? which transactions will be ignored? In your answer, you need to discuss the status of all transactions T1, T2, T3 and T4 and to explain why. System logs [start transaction, T1] [write transaction, T1, D, 20] [commit, T1] [Checkpoint] [start transaction, T2] [write transaction, T2, C, 50] [write transaction, T2, A, 10] [commit, T2] [start transaction, T3] [write transaction, T3, B, 10] [start transaction, T4] [write transaction, T4, D, 10] system crash sequence of

Given the system logs in the table below that shows the operations of four transactions T1, T2, T3 and T4. a) What is the purpose of using checkpoint? b) In case of recovery using deferred update, which transactions will be undone? which transactions will be redone? which transactions will be ignored? In your answer, you need to discuss the status of all transactions T1, T2, T3 and T4 and to explain why. System logs [start transaction, T1] [write transaction, T1, D, 20] [commit, T1] [Checkpoint] [start transaction, T2] [write transaction, T2, C, 50] [write transaction, T2, A, 10] [commit, T2] [start transaction, T3] [write transaction, T3, B, 10] [start transaction, T4] [write transaction, T4, D, 10] system crash sequence of

Database System Concepts

7th Edition

ISBN:9780078022159

Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan

Chapter1: Introduction

Section: Chapter Questions

Problem 1PE

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Similar questions

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