Oracle Database releases are categorized by five numeric segments that indicate release information.
Starting with Oracle Database 18c, Oracle provides quarterly updates in the form of Release Updates (Updates) and Release Update Revisions (Revisions). Oracle no longer releases patch sets. For more information, see My Oracle Support Note 2285040.1.
Oracle Database releases are released in
version release is designated in the form
major release version.0.0.0.0. The major release version is based on the last two digits of the year in which an Oracle Database version is released for the first time. For example, the Oracle Database version released for the first time in the year 2018 has the major release version of 18, and thus its
version release is
version_full release is an update of a
version release and is designated based on the major release version, the quarterly release update version (Update), and the quarterly release update revision version (Revision). The
version_full releases are categorized by five numeric segments separated by periods as shown in the following example:
Figure 1-2 Example of an Oracle Database Release Number
Description of "Figure 1-2 Example of an Oracle Database Release Number"
First numeral: This numeral indicates the major release version. It also denotes the last two digits of the year in which the Oracle Database version was released for the first time.
Second numeral: This numeral indicates the release update version (Update).
Third numeral: This numeral indicates the release update revision version (Revision).
Fourth numeral: This numeral indicates the increment version. This nomenclature can apply to updates in future releases.
Fifth numeral: This numeral is reserved for future use.
The first three numerals mainly identify an Oracle Database release.
Oracle strongly recommends that you apply the most recent release update (Update) or bundle patch or patch set update to your source and target databases before starting an upgrade, and before starting a downgrade.