Delete / drop database

Windows

Check where the ORACLE_HOME for this instance is

Start:Run... services.msc

Double click on OracleService<SID>, the first part of "Path to executable" is the home or regedit and go to HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE See list of homes

Find location of files to delete

Connect as sys and

select name from v$datafile;
select member from v$logfile;
show parameter control
show parameter dump
show parameter archive_dest

Stop the services related to the instance

set ORACLE_HOME=<oracle home>
oradim -delete -sid <SID>

*Clean up database files:
delete %ORACLE_HOME%\database\PWD<SID>.ora and any pfile, spfile and .dat files
Delete the files and directories shown by above queries

Check in Registry to make sure entries have gone from HKEY_LOCAL_MACHINE\SOFTWARE\ORACLE\KEY_<home>

Unix

Clean up RMAN repository

rman target sys/sys@DBTOGO catalog rman/rman@rmancat
RMAN> unregister database;
. oraenv
DBTOGO
dbca -silent -deleteDatabase -sourceDB DBTOGO
Connecting to database
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