Oracle SQL Jumpstart with Examples- P12: Review "As a consultant with more than 12 years of experience working with Oracle databases on a daily basis, reviewing this book was a unique and enjoyable experience. The SQL language is without doubt one of the most critical database skills and it is best learned by example. This book addresses that crucial need. Mr. Powell does an excellent job of clarifying the concepts by using meaningful and easy to understand examples. Frankly, I have not come across any other book on SQL that is as good a compilation of SQL concepts in a single. | 520 Privileges PRINCE originally granted the CREATE VIEW privilege to ARIEL. Revoked system privileges do not cause cascading revokes only object privilege revokes can do that. CREATE VIEW CA_ARTISTS AS SELECT FROM WHERE STATE_PROVINCE CA We will now examine some rules about revoking privileges. Using graphic examples here are some key points to remember about how revoking of privileges works. Revoked System Privileges DO NOT Cascade When you revoke a system privilege the revoke affects only the user you are naming and does not affect any objects or users created. For example SYSTEM grants the CREATE USER privilege WITH ADMIN OPTION to ASSISTANT. Then ASSISTANT creates a user named INTERN and grants her the CREATE USER privilege. Now INTERN creates another user named JOE. Figure illustrates these events. Figure One New User Is Created by Each of These Users SYSTEM ASSISTANT and INTERN. Assistant DBA SYSTEM CREATE USER ASSISTANT IDENTIFIED BY A123 GRANT CREATE USER TO ASSISTANT WITH ADMIN OPTION ASSISTANT f CREATE USER INTERN IDENTIFIED BY XYZ123 GRANT CREATE USER TO INTERN INTERN CREATE USER JOE IDENTIFIED BY JP 9833 Please purchase PDF Split-Merge on to remove this watermark. Privileges 521 Figure ASSISTANT Failed to Create MATTHEW but INTERN Created BETH. Now as the DBA you decide that your assistant does not need to create users at this point so you revoke the CREATE USER privilege from ASSISTANT. ASSISTANT can no longer create users however the users she created still exist. And INTERN who received the system privilege CREATE USER from ASSISTANT retains that privilege. Figure illustrates this idea by showing that ASSISTANT cannot create a user while INTERN can create a user. Revoked Object Privileges DO Cascade Revoking an object privilege does result in a cascading set of revoked privileges. For example imagine that SYSTEM grants SELECT on to ASSISTANT using the WITH
