1. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Tuesday, November 1, 2000 “Transaction processing” Lecture No. 18 OLTP

2. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts CONTENTS Concurrency control Transactions and schedules Serializability Anomalies due to concurrency Locking/ Time stamping OLTP

3. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts User SYTEM and SYS users Concurrency

4. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Role Connect (select, insert, update, delete, create tables) Authority Resource (Create tables, SP, triggers, indexes and clusters) DBA (All system privileges, grant privileges, unlimited space quota )

5. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Grant Granting system privileges grant role to user; grant CONNECT, RESOURCE to ARUL; Authority Granting object privileges grant priv on object to user; grant select on customerTable to ARUL;

6. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Guidelines 1. You cannot grant a privilege that you do not have 2. You cannot grant privileges on objects that you do not own. 3. You cannot grant privileges on objects for which you don’t have the authority to grant. 4. You cannot access objects for which you have not been granted privileges. Authority

7. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Creating roles Authority 1. Create role Create role CLERK; 2. Grant privileges to role grant create session to clerk; 3. Grant a role to users; grant clerk to ARUL; Teaser: Why should we create such roles

8. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Data dictionary Stores information that is used to manage the objects in the database. USER, ALL and DBA prefixes. DICTIONARY table Dictionary

9. Kansas State University Department of Computing and Information Sciences CIS 560: Database System Concepts Examples USER_OBJECTS USER_TABLES USER_VIEWS USER_CONSTRAINTS USER_INDEXES USER_SOURCE USER_USERS Dictionary