Implementation Method:
1. services. msc stop all Oracle services.
2. Start-> Program-> Oracle-OraHome81-> Oracle Installation Products-> Universal Installer
Unmount all Oracle products, but the Universal Installer cannot be deleted.
3. Run regedit, select HKEY_LOCAL_MACHINE \ SOFTWARE \ ORACLE, and press del to delete the entry.
4. Run regedit and select HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services. Scroll through the list and delete all Oracle entries.
5. Run refedit and select HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Services \ Eventlog \ Application to delete all Oracle entries.
6. Choose "start"> "Settings"> "Control Panel"> "system"> "advanced"> "environment variable" to delete Oracle settings in the environment variables CLASSPATH and PATH.
7. Delete \ Program Files \ Oracle directory
8. restart the computer to completely delete the Oracle directory.
9. In the event viewer, delete Oracle-related logs.
App: after deletion, there will actually be records in the registry. Generally, ctrl + f is used to remove the records.