Get Started with Performance Tuning Changes in This Release for Oracle Database 2 Day + Performance Tuning Guide Changes in This Release for Oracle Database 2 Day + Performance Tuning Guide This preface contains: Changes in Oracle Database Release 19c, Version 19.1 Changes in Oracle Database Release 18c, Version 18.1 Changes in Oracle Database 12c Release 2 (12.2) Changes in Oracle Database 12c Release 1 (12.1.0.2) Changes in Oracle Database 12c Release 1 (12.1.0.1)