Start log records found for all Beginning of log older transactions in undo list To rollback (during normal operation) begins Redo Pass End of log at crash! To rollback complete T2 is incomplete Log records added during at crash Undo list: T2 Undo Pass T2 rolled back in undo pass recovery newer Figure 19.5 Example of logged actions and actions during recovery.

Start log records found for all Beginning of log older transactions in undo list To rollback (during normal operation) begins Redo Pass End of log at crash! To rollback complete T2 is incomplete Log records added during at crash Undo list: T2 Undo Pass T2 rolled back in undo pass recovery newer Figure 19.5 Example of logged actions and actions during recovery.

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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