Here I am going to illustrate the procedure to patch oracle 19c database in windows enthronement, to apply APRIL 2021 CPU patches (19.11) RU (release update).
Download Windows Database Bundle Patch (19c) 19.11 from Oracle Support website.
Download the latest OPatch utility:
Ensure your run CMD as administrator:
Check your environment variables:
Stop Distributed Transaction Coordinator:
net stop msdtc
Go to the directory where the patch is downloaded
Apply the patches using the downloaded Opatch utility and copy it under your $ORACLE_HOME/OPatch directory:
Startup the Oracle services again:
sqlplus / as sysdba
SQL> alter pluggable database all open;
In CMD session (run it as administrator):
Then, check the registry that the patch is successfully applied:
select * from dba_registry_sqlpatch;