I have installed Oracle 11g on Windows 7
When I start sqlplus, it ask me for a username and password
Can anybody tell me what username needs to be inserted and when I try to type in any password, it doesn't allow me to type a single letter. Is there a reason why?
If you've forgotten the password for any user then you can reset by logging in as SYS:
sqlplus / as sysdba
And then:
alter user <username> identified by <password>;
If you've forgotten which users you have then you can run:
select username from all_users;
If you have only recently created the database it would be worthwhile restricting on CREATED, as the default database install comes with dozens of its own schemas. For instance, to find users added in the last week run this:
select * from all_users
where created > trunc(sysdate)-7;
Enter SYSTEM as user-name and the password entered during installing 11g works well for me!
The username refers to the schema to which you must connect to. Generally the hr schema is the sample schema that is available. The password will be the same password that you set during Oracle installation.
来源：https://stackoverflow.com/questions/8722302/what-username-password-should-be-entered-when-connecting-to-sqlplus-after-ins