对于全新安装的数据库，安装较新的PSU补丁集及CPU补丁都是必要的。

例如 10.2.0.4.x Database PSU 有如下发布，其中最新的是10.2.0.4.5

Patch	PSU Version
Patch 9654991	10.2.0.4.5
Patch 9352164	10.2.0.4.4
Patch 9119284	10.2.0.4.3
Patch 8833280	10.2.0.4.2
Patch 8576156	10.2.0.4.1

10.2.0.4.5 之前的PSU是累积补丁：

Patch Set Update (PSU) patches are cumulative. That is, the content of all previous PSUs is included in the latest PSU patch. PSU 10.2.0.4.4 includes all fixes previously included in PSU 10.2.0.4.3 。

而10.2.0.4.5 要基于之前的10.2.0.4.4 基础上来应用：

Patch Set Update PSU 10.2.0.4.5 is an overlay PSU whose base PSU is 10.2.0.4.4. This patch can only be applied in an Oracle home for which PSU 10.2.0.4.4 has already been installed.

安装这些PSU要确保你的OPatch是足够新的版本：

You must use the OPatch 10.2 version 10.2.0.4.8 or later to apply this patch. Oracle recommends that you use the latest released OPatch 10.2, which is available for download from My Oracle Support patch 6880880 by selecting the 10.2.0.0.0 release.

转载自 http://www.eygle.com/archives/2010/09/oracle_psu_patch.html

如何查看补丁

----------------------------

ccptdb<*ccptdb*/u01/product/oracle/OPatch>$opatch lsinventory
Invoking OPatch 11.2.0.1.3

Oracle Home       : /u01/product/oracle
Central Inventory : /u01/oraInventory
   from           : /etc/oraInst.loc
OPatch version    : 11.2.0.1.3
OUI version       : 11.2.0.1.0
OUI location      : /u01/product/oracle/oui
Log file location : /u01/product/oracle/cfgtoollogs/opatch/opatch2010-12-24_08-18-22AM.log

Patch history file: /u01/product/oracle/cfgtoollogs/opatch/opatch_history.txt

Lsinventory Output file location : /u01/product/oracle/cfgtoollogs/opatch/lsinv/lsinventory2010-12-24_08-18-22AM.txt

--------------------------------------------------------------------------------
Installed Top-level Products (1):

Oracle Database 11g 11.2.0.1.0
There are 1 products installed in this Oracle Home.

Interim patches (2) :

Patch 9352237      : applied on Fri Dec 24 08:09:58 CST 2010
Unique Patch ID: 12250325
   Created on 25 Mar 2010, 00:05:17 hrs PST8PDT
   Bugs fixed:
     8661168, 8769239, 8898852, 8801119, 9054253, 8706590, 8725286, 8974548
     8778277, 8780372, 8769569, 9027691, 9454036, 9454037, 9454038, 8761974
     7705591, 8496830, 8702892, 8639114, 8723477, 8729793, 8919682, 8818983
     9001453, 8475069, 9328668, 8891929, 8798317, 8820324, 8733749, 8702535
     8565708, 9036013, 8735201, 8684517, 8870559, 8773383, 8933870, 8812705
     8405205, 8822365, 8813366, 8761260, 8790767, 8795418, 8913269, 8897784
     8760714, 8717461, 8671349, 8775569, 8898589, 8861700, 8607693, 8642202
     8780281, 9369797, 8780711, 8784929, 8834636, 9015983, 8891037, 8828328
     8570322, 8832205, 8665189, 8717031, 8685253, 8718952, 8799099, 8633358
     9032717, 9321701, 8588519, 8783738, 8796511, 8782971, 8756598, 9454385
     8856497, 8703064, 9066116, 9007102, 8721315, 8818175, 8674263, 9352237
     8753903, 8720447, 9057443, 8790561, 8733225, 9197917, 8928276, 8991997, 8837736

Patch 8730312      : applied on Fri Dec 24 08:01:57 CST 2010
Unique Patch ID: 12177426
   Created on 7 Feb 2010, 06:41:26 hrs PST8PDT
   Bugs fixed:
     8730312

--------------------------------------------------------------------------------

OPatch succeeded.
ccptdb<*ccptdb*/u01/product/oracle/OPatch>$

Oracle PSU （Patch Set Update）- 10g补丁列表及如何查看补丁