About Administration Privileges for Startup and Shutdown

To start or shut down the Oracle instance, you must connect to the instance with a special connection privilege. There are two of these privileges: SYSDBA for fully empowered database administrators and SYSOPER for users who start and shut down the database, but have no privileges to access user objects.

When you create an Oracle database, there are two primary administrative user accounts that are automatically created: SYS and SYSTEM. Both of these users have full database administration privileges, but initially, only user SYS or SYSTEM can connect with the SYSOPER privilege. Therefore, until you grant the SYSOPER privilege to other users, you must connect to the Oracle instance as user SYS or SYSTEM to start and shut down the instance. When connecting (logging in) as user SYS, you must always specify that you are connecting AS SYSDBA.