Oracle 12C database provides a built-in utility file deinstall.bat ( sh ) that is used to uninstall Oracle Database 12 completely from the system. Below are some useful points before continuing the uninstallation:
1. The deinstaller will take care of stopping all the services run by Oracle database. For example, listener, database service etc
2. The deinstaller will completely remove all the directories inside the ORACLE_HOME directory such as /admin, /oradata, /diag etc
3. Run the Deinstaller either as administrator or Oracle Software installation owner
4. The deinstaller identifies the ORACLE_HOME directory automatically if it runs from the ORACLE_HOME\deinstall
In this section, I explained how to Uninstall Oracle Database Enterprise 12C edition from Windows
Uninstall Oracle Database 12C
1. Go into the ORACLE_HOME\deintall\ and run the deintaller.bat as Administrator or owner of the database
2. The de-installer opens on the screen. Verify the Listener name & Hit Enter
3. Verify the SID & Hit Enter
4. Check the SID and hit enter
5. Input ‘Y‘ and Hit Enter
6. The Oracle database uninstallation begins. The command windows closes once it completed the uninstallation.
7. The installer will remove all the directories from the ORACLE_HOME
8. Delete the app directory manually from the File Explorer
9. Manually, remove any user account that belongs to the database. That’s it. The database has been completely removed from the system.
