The logical clock timestamp scheme presented in this chapter provides the following guarantee: If event A happens before event B, then the imestamp of A is less than the timestamp of B. Note, however, that one cannot order two events based only on their timestamps. The fact hat an event C has a timestamp that is less than the timestamp of event O does not necessarily mean that event C happened before event D; C and D could be concurrent events in the system. Discuss ways in which he logical clock timestamp scheme could be extended to distinguish concurrent events from events that can be ordered by the happens-before elationship.

The logical clock timestamp scheme presented in this chapter provides the following guarantee: If event A happens before event B, then the imestamp of A is less than the timestamp of B. Note, however, that one cannot order two events based only on their timestamps. The fact hat an event C has a timestamp that is less than the timestamp of event O does not necessarily mean that event C happened before event D; C and D could be concurrent events in the system. Discuss ways in which he logical clock timestamp scheme could be extended to distinguish concurrent events from events that can be ordered by the happens-before elationship.

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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