Patches are a small collection of files that are copied over an existing installation. They are associated to particular versions of Oracle Products. Patches, when applied to the correct version of an installed product, results in an upgraded version of the product.Interim patches are bug fixes that are made available to customers in response to specific bugs. They require a particular base release or patchset to be installed before they can be applied. They generally address specific bugs for a particular customer. These patches are not versioned and are generally made available in a future patchset as well as the next product release.
OPatch is an Oracle supplied utility to assist you with the process of applying interim patches to Oracle's software. OPatch is a Java-based utility which requires the Oracle Universal Installer to be installed. It is platform independent and runs on all supported operating systems.
OPatch supports the following:
Applying an interim patch.
Rolling back the application of an interim patch.
Detecting conflict when applying an interim patch after previous interim patches have been applied. It also suggests the best options to resolve a conflict.
Reporting on installed products and interim patch.
The OPatch utility requires the following:
The Oracle home environment variable (
ORACLE_HOME) must point to a valid Oracle home directory and match the value used during installation of the Oracle home directory.
Java SDK 1.4 or higher, Java commands for Windows and ar, cp, fuser, and, make commands for UNIX must be made available.
The library path must be set correctly for Oracle Real Application Clusters environments. OPatch uses some APIs to detect if the system is Real Application Clusters. Ensure that the library path is set correctly as follows:
For Solaris LD_LIBRARY_PATH = $ORACLE_HOME/lib32:$ORACLE_HOME/lib For HP-UX - SHLIB_PATH=$ORACLE_HOME/lib32:/usr/lib