SYS and SYSTEM Users

SYS and SYSTEM Users
The following administrative user accounts are automatically created when you install
Oracle Database. They are both created with the password that you supplied upon
installation, and they are both automatically granted the DBA role.
■ SYS
This account can perform all administrative functions. All base (underlying) tables
and views for the database data dictionary are stored in the SYS schema. These
base tables and views are critical for the operation of Oracle Database. To maintain
the integrity of the data dictionary, tables in the SYS schema are manipulated only
by the database. They should never be modified by any user or database
administrator. You must not create any tables in the SYS schema.
DBA Enables a user to perform most administrative functions,
including creating users and granting privileges; creating and
granting roles; creating, modifying, and deleting schema objects
in any schema; and more. It grants all system privileges, but
does not include the privileges to start or shut down the
database instance. It is by default granted to users SYS and
SYSTEM.
See Also:
■ "Administering Roles" on page 7-6
■ "Administering Database User Accounts" on page 7-8
■ Chapter 8, "Managing Schema Objects"
■ Oracle Database 2 Day + Security Guide for more information about
privileges and roles
■ Oracle Database SQL Language Reference for tables of system
privileges, object privileges, and predefined roles
■ Oracle Database Concepts for an overview of database security
Role Name Description
About Administrative Accounts and Privileges
Administering User Accounts and Security 7-5
The SYS user is granted the SYSDBA privilege, which enables a user to perform
high-level administrative tasks such as backup and recovery.
■ SYSTEM
This account can perform all administrative functions except the following:
- Backup and recovery
- Database upgrade
While this account can be used to perform day-to-day administrative tasks, Oracle
strongly recommends creating named users account for administering the Oracle
database to enable monitoring of database activity.
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