1. Class 4 Agenda Database Management Systems Database Management Systems Chapter 4: Moore’s Law Chapter 4: Moore’s Law Midterm Case Midterm Case

2. Database Management Systems: What? Software that owns and manages data Software that owns and manages data Two models Two models –Relational DBMS –Object-oriented DBMS Provides “Storage” layer to applications Provides “Storage” layer to applications Can provide logic (constraints) to applications Can provide logic (constraints) to applications

3. Database Management Systems: Why? Insulate users from data mechanics Insulate users from data mechanics Ensure business rules are universally applied Ensure business rules are universally applied Allow simultaneous access Allow simultaneous access Increase granularity of access Increase granularity of access Standardize access language (SQL) Standardize access language (SQL)

4. Database Management Systems: Who? Oracle Oracle Microsoft: SQLServer Microsoft: SQLServer IBM: UDB / DB2 IBM: UDB / DB2 Open Systems: MySQL, PostGres, … Open Systems: MySQL, PostGres, … CA, Sybase, … CA, Sybase, …

5. The DBMS Server layers DBMS Storage Database Tablespace Table Tablespace Table DBMS Server Server Instance Schema Instance Schema “Mounts” Application Heavy Client (Sqlplus) App Server Web Server (isqlplus) DBMS Client “Connects”

6. DBMS Functions Data Integrity Data Integrity –Accurate and reliable Access Control Access Control –Views –Grants –Multiple levels of access DataAccess API DataAccess API –Single well-known interface Single point of control Single point of control –DBMS Owns the files Utilities Utilities

7. Data Integrity Locking Locking –Allows simultaneous use –Different levels available Constraints Constraints –Limits on acceptable entries –Discussed in detail later Logging Logging –Undoing failed work –Recording completed work

8. Access Control Support for users and roles Support for users and roles Granularity for data (Views) Granularity for data (Views) –Vertical –Horizontal Granularity for Function Granularity for Function –Read vs change –Procedural access only

9. SQL API Defines the access syntax Defines the access syntax Open Standard Open Standard Extensions for each vendor Extensions for each vendor

10. Relational DBMS Concepts Value-based relations Value-based relations Joins Joins Tables and Views Tables and Views Set Processing Set Processing

11. Object-Oriented DBMS’s Purpose: Make storage a service Purpose: Make storage a service Classes and Objects Classes and Objects –Basic logic joined to data Object “behavior” Object “behavior” Behavior request mechanism (messages) Behavior request mechanism (messages)

12. Object-Oriented DBMS Concepts Inheritance Inheritance –Proper scope for all data, behaviors Encapsulation Encapsulation –Inner workings hidden from users–Inner workings hidden from users –Focus on behavior, not process Polymorphism Polymorphism –Each class can interpret requests

13. Chapter 4 Comments: Moore’s Law Reasons for improvement Reasons for improvement Caching Caching Applies to network, storage as well Applies to network, storage as well Tiers of computing need Tiers of computing need Parallel processing Parallel processing

14. Group Reviews: Moore’s Law Pick one, 4 minute response Impact on “cash cow” phase of product delivery Impact on “cash cow” phase of product delivery Impact on purchasing decisions Impact on purchasing decisions Is it coming to an end? Is it coming to an end? Why does network speed come in bigger increments? Why does network speed come in bigger increments? The sixth wave? The sixth wave? Where is the most waste? Where is the most waste?

15. Midterm Case Introduction: Toyota, The Big Fix Issues Issues –Project Management –Governance? –Reporting Assignment Assignment –Read –Questions on Wednesday?