Oracle Database releases are categorized by five numeric segments that indicate release information.
Oracle provides quarterly updates in the form of Release Updates (Updates, or RU) and Release Update Revisions (Revisions, or RUR). Oracle no longer releases patch sets or bundle 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
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_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, or RU).
Third numeral: This numeral indicates the release update revision version (Revision, or RUR).
Fourth numeral: This numeral is reserved for future use. Currently it is always set to 0.
Fifth numeral: Although only the first three fields are commonly used, the fifth field can show a numerical value that redundantly clarifies the release date of a release update (RU), such as 22.214.171.124.200414.
The first three numerals mainly identify an Oracle Database release.
Oracle strongly recommends that you apply the most recent Release Update to your target databases before starting an upgrade, and before starting a downgrade. If possible, also ensure that your source environment is patched. Release updates are cumulative. If you are also updating an Oracle Grid Infrastructure environment, then always apply the latest Release Update to the Grid environment first before updating Oracle Database Oracle homes. For more information about updates, refer to My Oracle Support note 2118136.2.