Consider the following two transactions: TI-R(B), W(B), R(C), R(A) T2-R(B). W(B) Say that sharing lock, exclusive lock, and unlock actions are inserted by the scheduler, resulting in the following annotated transactions: T1= X(B), R(B), W(B), S(C), R(C), S(A), U(B), R(A), U(C), U(A) T2-X(B), R(B), W(B), U(B) Cascading rollback is not possible for the above schedule. O True O False

Consider the following two transactions: TI-R(B), W(B), R(C), R(A) T2-R(B). W(B) Say that sharing lock, exclusive lock, and unlock actions are inserted by the scheduler, resulting in the following annotated transactions: T1= X(B), R(B), W(B), S(C), R(C), S(A), U(B), R(A), U(C), U(A) T2-X(B), R(B), W(B), U(B) Cascading rollback is not possible for the above schedule. O True O False

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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