A few working sqls to save your ass

1. login the super user on the oracle installation machine;

sqlplus / as sysdba

2.unlock the default test account hr, another one is scott/tiger also locked

alter user hr account unlock;

3.set the password for this account

alter user hr identified by hr;

4. find all the usernames on the system

select username from dba_users;

less priviledge

select username from all_users;

5. login with one command

sqlplus hr/hr;

6. view history close by default

hist list

7.view which database you wanna connect to (execute this as sysdba)

SELECT NAME FROM v$database;