Redo and Undo

  • Thomas Kyte
  • Darl Kuhn
Chapter

Abstract

This chapter introduces you two of the most important pieces of data in an Oracle database: redo and undo. Redo is the information Oracle records in online (and archived) redo log files in order to “replay” your transaction in the event of a failure. Undo is the information Oracle records in the undo segments in order to reverse, or roll back, your transaction.

Keywords

Index Block Oracle Database Transaction Size Buffer Cache System Crash 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Copyright information

© Thomas Kyte 2014

Authors and Affiliations

  • Thomas Kyte
    • 1
  • Darl Kuhn
    • 1
  1. 1.VAUnited States

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