System Users
The Oracle database creates two users when you install Oracle:
- SYS
The schema for SYS contains the base tables and views used for the data dictionary. You should never change any of these tables. The SYS user has the DBA role. (Roles are described in the “Roles” section later in this chapter.) The default password for SYS is CHANGE_ON_INSTALL.
- SYSTEM
The SYSTEM username is used to create additional tables and views for administrative information. The SYSTEM user has the DBA role. The default password for SYSTEM is MANAGER.
When you create an Oracle database using the CREATE DATABASE statement, you can use the USER SYS IDENTIFIED BY password and USER SYSTEM IDENTIFIED BY password clauses to protect access by these powerful precreated users.