Database Reference
In-Depth Information
rendering the database useless. Log in as the SYS user primarily when
performing these tasks. A SYS user connection always requires the
SYSDBA or SYSOPER (special system privileges) to perform the fol-
lowing tasks:
Exporting and importing data.
Shutting down and starting up the database.
Database recovery.
SYSTEM
. SYSTEM is the database administrator. This user is fre-
quently used by the DBA to perform day-to-day tasks of monitoring
and administering the database. SYSTEM can do many of the same
tasks as the SYS user, without the danger of accidentally damaging
internal tables or bouncing the database. Log in as the SYSTEM user
when performing these tasks:
Creating new users, changing user passwords.
Assigning system privileges to users or roles (you will understand
what this means when you get further into this chapter).
Monitoring database activity and performance.
Adjusting database parameters (usually to improve performance).
Adding more space to the database.
Feature-Related Users
. These users are the owners of tables and other
objects related to specific Oracle Database 10
features such as replica-
tion, spatial support, and advanced queuing. Depending on how many
features were installed with your database, there may be quite a few of
these users. Do not log in as any of these users unless specifically
instructed to do so by Oracle Database 10
g
g
documentation.
Note:
In the past, passwords for SYS and SYSTEM were defined as part of
the database creation process and defaulted to “change_on_install” and
“manager,” respectively. Oracle Database 10
forces password definition on
installation. You know what they are if you installed the database. If not,
ask the person who did the installation for the passwords. If you need those
g
passwords, they will be given to you.
23.1.2
Creating Users
The syntax for creating users is much easier than the syntax for creating a
table! There are far fewer options. Figure 23.1 shows the syntax.
