Database Reference
In-Depth Information
Figure 3.4
Table Definitions
Include Table and
Column
Specifications.
Many users, sometimes thousands, might share a single Oracle data-
base. A user is any person who can log into the database instance. There
are several ways to authenticate a user logging into the database (see Chap-
ter 23); the typical method is to assign each person a unique user name
and a password.
When so many individuals access the same database, the easiest way to
keep track of them is to group them together by duties or roles. Oracle pro-
vides the capability to assign privileges to a role and then assign the role to
one or more users.
For example, one user might be the database administrator (DBA). That
user has the authority to start and stop the database instance, add new
users, change passwords, assign other users various privileges, and so on.
Another user may need to create tables, while a third user might need only
to log in and view or modify data in someone else's tables. Oracle Database
provides predefined roles for these typical groups of users:
CONNECT:
This role gives users the right to log into the database.
RESOURCE:
This role authorizes users to create tables (and other
structures, such as indexes) in the database.
