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OCA /OCP Oracle Database 11g A ll-in-One Exam Guide- P27:There is an ever increasing demand for staff with IT industry certification. The benefits to employers are significant—they can be certain that staff have a certain level of competence—and the benefits to the individuals, in terms of demand for their services, are equally great. Many employers are now requiring technical staff to have certifications, and many IT purchasers will not buy from firms that do not have certified staff. | OCA OCP Oracle Database 11g All-in-One Exam Guide 216 3. Confirm that the users have been created with Database Control. From the database home page the navigation path is the Server tab and the Users link in the Security section. They should look something like those shown in this illustration 4. From SQL Plus attempt to connect as user SALES connect sales sales 5. When prompted select a new password such as oracle . But it won t get you anywhere because user SALES does not have the CREATE SESSION privilege. 6. Refresh the Database Control window and note that the status of the SALES account is no longer EXPIRED but OPEN because the password has been changed. Grant and Revoke Privileges By default no unauthorized user can do anything in an Oracle database. A user cannot even connect without being granted a privilege. And once this has been done you still can t do anything useful or dangerous without being given more privileges. Privileges are assigned to user accounts with a GRANT command and withdrawn with a REVOKE. Additional syntax can give a user the ability to grant any privileges they have to other users. By default only the database administrators SYS and SYSTEM have the right to grant any privileges. The user that grants one or more privileges to another user is referred to as the grantor while the recipient is referred to as the grantee. Privileges come in two groups system privileges that generally speaking let users perform actions that affect the data dictionary and object privileges that let users perform actions that affect data. System Privileges There are about two hundred system privileges. Most apply to actions that affect the data dictionary such as creating tables or users. Others affect the database or the instance such as creating tablespaces adjusting instance parameter values or establishing a session. Some of the more commonly used privileges are Chapter 6 Oracle Security 217 CREATE SESSION This lets the user connect. Without this you .