Patch-related terms are often encountered when using Oracle's technical support services. Now to explain some of these terms:
Interim patch/One-off patch: We often say a small patch, a patch released to fix a certain (several) bugs. This patch is recommended to be tested on the test library and then installed on the production library.
Merged patch: Merged patch. This Merged Patch needs to be provided when there are conflicts between several small patches and cannot be installed at the same time. Patch conflicts are mainly due to two or more patches modifying the same file, but the modified content is different.
Bundle patch: A patch set that fixes multiple bugs. Oracle on the Windows platform has no small patches, only this Bundle Patch. This patch set is released periodically (at least once a season). This patch set is cumulative (cumulative), that is, each Bundle patch will contain all previous Bundle Patches. For example Windows Bundle Patch 16, it will contain all 15 previous Bundle Patches, so we always recommend installing the latest Bundle Patch. The Window Bundle Patch of Oracle's cluster software and database software is the same, such as Windows Bundle Patch 16 (patch number 16167942, which can be applied to both the cluster and the database).
To know the patch number of Windows Bundle Patch, you can refer to MOS document:
Note 161549.1 Oracle Database, Networking and Grid Agent Patches for Microsoft Platforms
Critical Patch Update (CPU):Released quarterly to fix some security patches, it is cumulative. It has now been renamed Security Patch Update (SPU).
Click the link below to view specific issues fixed by each CPU:
http://www.oracle.com/technetwork/topics/security/alerts-086861.html
Patch Set Update (PSU): Released quarterly, fixes more serious Some issues, including CPU per season, are cumulative. Although the fifth digit of the database version is used when describing the PSU, such as Database PSU 11.2.0.3.5, in fact, the version of the database will not be changed after the PSU. The version seen from v$version is still 4 bits (11.2.0.3.0), the 5th bit is still 0. Note that there is no CPU and PSU on Windows, Oracle's cluster software and database software use different PSUs.
You can refer to the following MOS document for the specific patch numbers of each quarter's CPU, PSU, Windows Bundle Patch:
Note 1454618.1 Quick Reference to Patch Numbers for Database PSU, SPU(CPU), Bundle Patches and Patchsets
Patch set: It is in the major version The patch set released on , fixes a lot of bugs, and may include some enhancements. For example, 11.2 is a major version, then 11.2.0.2 is a Patch set. This patch set has undergone rigorous integration testing and is also cumulative. So we always recommend installing the latest Patch Set.
Diagnostic patch:Diagnostic patch. Sometimes when diagnosing a problem, in order to obtain more diagnostic information, Oracle's development department will provide a Diagnostic Patch, which is not to fix the problem, but to diagnose the problem.
Composite Patch: Starting from Database PSU 11.2.0.3.2 in April 2012, a new concept called Composite Patches was introduced. This is a new type of patch pack, which is different from other cumulative patch packs. If you install Composite Patches for the first time, then all the patches included in the Composite Patches will be installed. Subsequent installation of Composite Patches will only install the changed parts and newly added patches compared to the previous Composite Patches.
PSU is a composite patch, take PSU as an example to illustrate.
The composite patch installed for the first time is PSU 11.2.0.3.2:
Interim patches (1) :
Patch 13545268: applied on Fri Dec 09 10:59:28 EST 2011
Patch Description: "Database Patch Set Update : 11.2.0.3.2 (13545268)" <==Changes and Added SectionsCreated
on 2 July 2012, 07:52:00 hrs PST8PDT
Sub-patch 13343438; "Database Patch Set Update : 11.2.0.3.1 (13343438)" <== Sub -patch
Bugs fixed:
9275072, 9352237 ...
安装下一个composite patch PSU 11.2.0.3.3时，只需要安装有变化的部分和新增加的patches，不需要再安装之前已经安装的11.2.0.3.1 和11.2.0.3.2，之前已经安装的这部分就称为sub-patch：
Patch 13795248 : applied on Fri Dec 10 10:00:28 EST 2011
Patch Description: "Database Patch Set Update : 11.2.0.3.3 (13795248)" <==变化和新增的部分
Created on 2 July 2012, 07:52:00 hrs PST8PDT
Sub-patch 13545268; "Database Patch Set Update : 11.2.0.3.2 (13545268)" <==Sub-patch
Sub-patch 13343438; "Database Patch Set Update : 11.2.0.3.1 (13343438)" <==Sub-patch
Bugs fixed:
9275072, 9352237 ...
Composite Patches 的好处是减少补丁的安装量，减少与已经安装上补丁的冲突。
在MOS文档中有针对Composite Patches详细的说明：
Note 1376691.1 Composite Patches for Oracle Products [Video]
上面提到的所有补丁都会有一个补丁号，如果已经知道了补丁号，就可以直接使用下面的链接来下载这个补丁：
https://updates.oracle.com/download/补丁号.html
输入MOS的账号、密码就可以。
比如：11.2.0.3.0 PATCH SET 下载链接：
https://updates.oracle.com/download/10404530.html
Oracle推荐打的补丁，可以参考MOS文档：
Note 756671.1 Oracle Recommended Patches -- Oracle Database
（推荐打最新版本的Patch set、PSU/CPU及 Windows Bundle Patch）