1. list inventory details of patch.

$ORACLE_HOME/OPatch/opatch lsinventory

2. list patchsets applied :

$ORACLE_HOME/OPatch/opatch lspatches

3. Find opatch version:

$ORACLE_HOME/OPatch/opatch version

4. Find details of a particular patch(before applying):

$ORACLE_HOME/OPatch/opatch query -all {PATCH_PATH}

$ORACLE_HOME/OPatch/opatch query -all /software/PSUPATCH/30089984

5. Apply a patch to RDBMS HOME:

-- You may need to shutdown the database and listener services:

cd /SOFTWARE/PSUPATCH/30089984 -- Go to the patch path:
$ORACLE_HOME/OPatch/opatch apply

6. Rollback an patch from RDBMS HOME:

$ORACLE_HOME/OPatch/opatch rollback -id [patch_id]
$ORACLE_HOME/OPatch/opatch rollback -id 30089984

7. Apply one off patch in grid_home:

root # $GI_HOME/crs/install/rootcrs.sh -prepatch. 


oracle$ cd /SOFTWARE/PSUPATCH/30089984 -- Go to the patch path:
oracle$ $GRID_HOME/OPatch/opatch apply


root# $GI_HOME/crs/install/rootcrs.sh -postpatch

8. Check conflict against ORACLE_HOME

- go to patch folder.
cd 27734982

[27734982]$ $ORACLE_HOME/OPatch/opatch prereq CheckConflictAgainstOHWithDetail -ph ./

9.Check whether active executables are running:

- go to patch folder.
cd 27734982


[27734982]$ $ORACLE_HOME/OPatch/opatch prereq CheckActiveFilesAndExecutables -ph ./

10.Opatch command using different inventory location:

$ORACLE_HOME/OPatch/opatch lsinventory -invPtrLoc /etc/orainv/orainventory