Book Image

Oracle Database 12c Backup and Recovery Survival Guide

Book Image

Oracle Database 12c Backup and Recovery Survival Guide

Overview of this book

The three main responsibilities of a successful DBA are to ensure the availability, recoverability, and performance of any database. To ensure the recoverability of any database, a DBA needs to have a strong backup and recovery skills set. Every DBA is always looking for a reference book that will help them to solve any possible backup and recovery situation that they can come across in their professional life. Oracle Database 12c Backup and Recovery Survival Guide has the unique advantage to be a reference to all Oracle backup and recovery options available, making it essential for any DBA in the world. If you are new to Oracle Database, this book will introduce you to the fantastic world of backup and recovery that is vital to your success. If you are an experienced DBA, this book will become a reference guide and will also help you to learn some possible new skills, or give you some new ideas you were never aware about. It will also help you to easily find the solution to some of the most well known problems you could find during your career as a DBA. This book contains useful screenshots, scripts, and examples that you will find more than useful. Most of the books currently available in the market concentrate only on the RMAN utility to backup and recovery. This book will be an exception to the rule and will become a must-have reference, allowing you to design a real and complete backup and recovery strategy. It covers the most important topics on Oracle database such as backup strategies, Nologging operations, new features in 12c, user managed backups and recoveries, RMAN (including reporting, catalog management, troubleshooting, and performance tuning), advanced data pump, Oracle Enterprise Manager 12c and SQL Developer. "Oracle Database 12c Backup and Recovery Survival Guide" contains everything a DBA needs to know to keep data safe and recoverable, using real-life scenarios.
Table of Contents (22 chapters)
Oracle Database 12c Backup and Recovery Survival Guide
Credits
About the Author
Acknowledgement
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

Crash and media recovery


In general, database recoveries can be categorized into two broad domains:

  • Crash recovery

  • Media recovery

Crash recovery (a.k.a. instance recovery) is a more subtle form of database recovery because all that is lost is the database instance. Since it's just the instance that's lost and not any physical file of the database, the recovery won't need any physical file(s) to be restored. The background process SMON will initiate the recovery automatically at the time of the next database startup. In this recovery, only the online redo logs belonging to a single thread (for a single instance) or of multiple failed threads are used for a Real Application Cluster (RAC) database.

Note

Many DBAs often use the terms instance and crash recovery interchangeably. However, it is actually wrong to do so. In a single instance, the loss of one instance is going to bring down its database as well. So a recovery in this case can be called either an instance or a crash recovery. But in an...