Editing Oracle Database (section)

=== Patch updates and security alerts ===

Prior to Oracle Database 18c, Oracle Corporation released Critical Patch Updates (CPUs) and Security Patch Updates (SPUs)<ref>{{cite book|url=https://books.google.com/books?id=bnx9_MkBimcC|title=Oracle Data Guard 11gR2 Administration Beginner's Guide|last1=Baransel|first1=Emre|publisher=Packt Publishing Ltd|isbn=9781849687911|date=2013|quote=You should not get confused between Critical Patch Update (CPU) and Security Patch Update (SPU) as CPU terminology has been changed to SPU from October 2012.|access-date=2014-01-15|archive-url=https://web.archive.org/web/20161123144706/https://books.google.com/books?id=bnx9_MkBimcC|archive-date=23 November 2016|url-status=live}}</ref> and Security Alerts to close security vulnerabilities. These releases are issued quarterly; some of these releases have updates issued prior to the next quarterly release.

Starting with Oracle Database 18c, Oracle Corporation releases Release Updates (RUs) and Release Update Revisions (RURs).<ref>{{cite web|url=https://docs.oracle.com/en/database/oracle/oracle-database/12.2/dbptc/patch-delivery-methods-for-oracle-database-12c-release-2-12-2-0-1-and-later-versions-243888991.html |title=Patch Delivery Methods for Oracle Database 12c Release 2 (12.2.0.1) and Later Versions |publisher=Docs.oracle.com |date= |accessdate=2022-03-16}}</ref> RUs usually contain security, regression (bug), optimizer, and functional fixes which may include feature extensions as well. RURs include all fixes from their corresponding RU but only add new security and regression fixes. However, no new optimizer or functional fixes are included.