Critical Patch Updates

CPU Critical Patch Update are security Fixes for oracle products including database
and are released in mid of following months

January
April
July
October

The Steps to follow are neatly mentioned in the Readme file that comes along with
the patch.

For applying the patch we use the utility Opatch provided by oracle
Opatch is Oracle Interim Patching Tool, it is used for patching the
installed oracle software, specifically the oracle home, opatch
is located at %ORACLE_HOME%\bin directory

When you start applying cpu patch, first the earlier patch is rolled back,
after which the current patch is applied automatically.

Windows

Following are the brief steps

1) Shut down the database instance cleanly

2) Backup up the %ORACLE_HOME%, and Program Files/Oracle/inventory folder.

3) Unzip the patch

4) Set the oracle_home environment variable, Check the earlier patch for the

    ORACLE_HOME, by executing opatch lsinventory

5) Go to the extracted patch folder, execute Opatch apply, this will update

    the oracle home.

6) Logs for the above are available at %Oracle_home%\cfgtoollogs\opatch\  direcory

    in file with the installation time stamp.

7) After patch has been applied, startup the database.

8) Execute the catcpu.sql from the %ORACLE_HOME%\BUNDLE\Patch<Patch-ID> direcory

9) Follow the readme document for views recompilation.


History of all the commands executed with opach are maintained

 in %Oracle_home%\cfgtoollogs\opatch\Opatch_history.txt