UNIX uses the concept of a DBA group. The root account cannot be used to install Oracle Database.

A separate Oracle Database account must be created manually.

On Windows, Oracle Database must be installed by a Windows username in the Administrators group. The user name is automatically added to the Windows local group ORA_DBA, which receives the SYSDBA privilege. This allows the user to log in to the database using CONNECT / AS SYSDBA and not be prompted for a password.

You can also create an ORA_OPER group to grant SYSOPER privileges to the other Windows users.

Password files are located in the ORACLE_HOME\database directory and are named pwdSID.ora, where SID identifies the Oracle Database instance.