You are given data of actions of total 3 transactions i.e, Tp, Tq and Tr. R for read and W for write. As you know the concept of strict two-phase locking: after all the actions are completed, only then transaction is unlocked. So to solve this you have exclusive and shared locks i.e, "xl(data item)" and "sl(data item)" respectively. Each of the action's order is interleaved. Write down for all the given questions, how the transactions should perform using the necessary locks and unlocks so that the given actions occur. Also mention to write the action too. i. ii. iv. v. vi. Tp: Rp (A) Tq: Wq (B) Tp: Wp (B) Tr. Wr (C) Tp: Wp (A) Tr. Wr (B)

You are given data of actions of total 3 transactions i.e, Tp, Tq and Tr. R for read and W for write. As you know the concept of strict two-phase locking: after all the actions are completed, only then transaction is unlocked. So to solve this you have exclusive and shared locks i.e, "xl(data item)" and "sl(data item)" respectively. Each of the action's order is interleaved. Write down for all the given questions, how the transactions should perform using the necessary locks and unlocks so that the given actions occur. Also mention to write the action too. i. ii. iv. v. vi. Tp: Rp (A) Tq: Wq (B) Tp: Wp (B) Tr. Wr (C) Tp: Wp (A) Tr. Wr (B)

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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