How to find whether the one-off Patches will conflict or not ?

 It is difficult to predict whether or not the Patches will conflict without actually applying them, but we can use the OPatch tool to check the same without actually applying the Patches to the Oracle Home

1. Make sure that the latest opatch version is being used  (You should download the latest OPatch via Metalink Patch 6880880 ) and  unzip it  under  $ORACLE_HOME
2. After confirming that you have the latest version of OPatch, proceed to download all the patches that you intend to install and unzip them into the same directory  (e.x $HOME/patches)
3. unzip them under  patch directory  (e.x $HOME/patches)
4. Run the following command to check whether there are any conflicts among the patches to be applied (e.x patch directory  is  $HOME/patches )
   
    opatch prereq CheckConflictAmongPatchesWithDetail -phBaseDir $HOME/patches
5. Run the following command to check whether there are any conflicts between the patches to be applied and the patches already applied in the Oracle Home (e.x patch directory is $HOME/patches )
   
   opatch prereq CheckConflictAgainstOHWithDetail -phBaseDir  $HOME/patches