This book, written by Sambaiah Sammeta and Sukumar Chillakuru, and technically reviewed by Venkata Ravi Kumar Yenugula will cover most of the scenarios for upgrading the Oracle database from versions 11g, 12c, and 18c databases to Oracle version 19c. This book describes the best methods that can be used to upgrade the Oracle databases, and mainly deals with how to use the Oracle’s ‘AutoUpgrade’ utility to upgrade the databases from the lower versions to Oracle 19c with minimal manual intervention. This book covers the various scenarios tested against the Real Application Clusters databases with Physical Standby databases, and also covers the test cases for both the non-container databases and the multitenant databases. This book also contains the various downgrade scenarios tested and explains both the benefits and pitfalls with each of the downgrade processes. The book is releasing at the right time as Oracle is strongly recommending to use the ‘AutoUpgrade’ tool to upgrade the Oracle databases. This book covers most of the scenarios that a DBA can find in a real time environment, and most importantly, each chapter is well tested and has hands-on steps, making this book an extremely helpful guide for the Oracle Database upgrade process. I would like to congratulate Sambaiah Sammeta and Sukumar Chillakuru for this excellent book. It is a must have book for every DBA working on the Oracle Database upgrades