User Access Control

In this chapter, you will learn about and demonstrate knowledge in the following areas of user access and privileges in the Oracle database:

• Creating users
• Granting and revoking object privileges
• Using roles to manage database access

The basic Oracle database security model consists of two parts. The first part consists of password authentication for all users of the Oracle database. Password authentication is available either directly from the Oracle server or from the operating system supporting the Oracle database. When Oracle’s own authentication system is used, password information is stored in Oracle in an encrypted format. The second part of the Oracle security model consists of controlling which database objects a user may access, the level of access a user may have to these objects, and whether a user has the authority to place new objects into the Oracle database. At a high level, these controls are referred to as privileges. We’ll talk about privileges and database access later in this section.
Create Users
The most basic version of the command for creating users defines only the user we want to create, along with a password, as seen in the following example:
Create User USERNAME identified by PASSWORD;
create user turner identified by ike;
Tip :
The user does not have privileges at this point. The DBA can then grant privileges to the user. The privileges determine the actions that the user can do with the objects in the database. Also, usernames can be up to 30 characters in length and can contain alphanumeric characters as well as the $, #, and _ characters.