Drop database by command line
$ sqlplus “/as sysdba”
SQL> select instance_name, status from v$instance;
SQL> shutdown immediate;
SQL> startup mount
SQL> alter system enable restricted session;
SQL> drop database;
Drop database by DBCA
$cd $ORACLE_HOME/bin
$./dbca
DBCA-> Click “Delete a Database”
-> Select the database name
-> Click “Finish”
