Chapter 5 Database Management

1. Chapter 5Database Management The Strategic Management of Information Systems

2. Transaction Processing System Input Process Output Communication Information

3. Today’s Organization • Enterprise-Wide Development • Entity Relationship Diagram • General Information Systems Model • Object-Oriented Definition • Implementation of Suite Approach • Business Transaction Processing

4. Steps Toward Integration • Windowing Operating System • OS/2 Presentation Manager • Windows • X-Windows (Sun) • Transaction Processing Systems • Payroll Services • Sales Order Processing Systems • Process Control Systems • Corporate Accounting Systems

5. Steps Toward Integration • Multi-Tasking • Allow Users to run different programs at the same time • Windows • OS/2 (Presentation Manager) • XWindows • Networks • Enable Dynamic Integration from Several Sources

6. Integration • Vertical • Different Levels of Production • ex: Oil Company • Horizontal • Retail Stores • ex:WalMart

7. Steps Toward Business Process Redesign Develop Business Vision and Process Objectives Prioritize Objectives and Set Targets Identify Process to Be Redesigned Identify Critical or Bottlenect Processes Understand and Measure Existing Processes Identiy Current Problems and Set Baseline Identify Information Technology Levers Brainstorm new Process Approaches Design and Build a Prototype of the Process Implement Organizational and Technical Aspects

8. Database Management Structure • Develop structure of each record according to selected data model • Load data into database • Update records in database • Generate reports from data in database • Maintain integrity of data in database • Maintain security by means of multilevel passwords

9. Database Management System Functions • Data Definition Language (DDL) • Data Manipulation Language (DML) • Query Language • Report Writer • Graphics Generator • Host Language Interface (HLI) • Procedural Language • Data Dictionary

10. Logical Model • Entity-Relationship Diagram • Entities • Relationships Between Entities • Data Normalization • Process of eliminating data redundancies and functional dependencies within the logical model

11. Database Types • Hierarchical • Network • Relational

12. Systems Advantage • More Flexible Systems • More Reuse of Logic • Less Bugs • Shorter Development Time • Lower Maintenance Costs

13. Business Advantage • Reduce Development Cost • Increase Ability to Compete • Increase Focus of Business on Business Opportunities • Outsourcing

14. Integration/Links • Static • Hard-Coded • Import • Dynamic • Linked • Dynamic Data Exchange (DDE) • Hot-Linked • Object-Linking and Embedding (OLE) • Original Software Package Automatically started when chosen

15. Resources Line Planned Systems Project Load Planning Cycle Resources Requirements Matrix

16. Strategic Factors • Productivity • Increase Effectiveness and Efficiency of Operations • Differentiation • Make Products and Services Different from those of the Competitor • Management • Help Managers Perform Planning, Controlling, and Decision-Making Tasks Better

17. Systems Project Proposals • Telecommunications • Transmission of Voice/Data/Graphics • Innovative Applications • Electronic Data Interchange

18. Project Schedule Report • Identifies Systems Project and Estimated Completion Date

19. Systems Planning Approach/Feasibility • Technical • Availability of existing technology • Economic • Commit Sufficient Funds to Develop and Implement the System • Legal • Compliance with the Law • Operational • Efficacy and Functionality of Systems Project Proposal • Schedule • Proposed Timetable

20. Object-Orientation • Different than Transmitting Raw Bits of Data • Hardware Connections • Access Controls • Simple Data Formats • Software Agents • object-oriented programs written to perform specific tasks in response to user requests • agents know how to exchange object attributes • agents have the ability to activate object functions in other agents • Multimedia • Integration of Text, Video, Sound, Pictures, Animation

21. Object-Oriented Development • Object-Oriented Analysis • Building Real-world models, using object-oriented view • Determine classes of objects in problem • Identify similarities in objects through classification • Object-Oriented Design • Decompose knowledge and actions into detailed object-oriented model • Logical View: classes and objects • Physical View: modules and physical implementation • Object-Oriented Programming • Programs are organized as cooperative collections of objects, each of which represents an instance of a class

22. Cyclical Nature Identify Classes and Objects Specify Class and Object Interfaces and Implementation Identify Class and Object Semantics Identify Class and Object Relationships

23. Elements of Object Model • Abstraction • Objects or Classes • emphasize the particulars of object that distinguish it • deemphasize the details that are not important • Hides various behaviors of an object from the user • Encapsulation • Hide the information about how a class is implemented from other classes or objects that may reference a class • Hides implementation details from a user • Modularity • Class or program is broken down into smaller, more understandable parts • Well-defined boundaries with less complexity

24. Elements of Object Model • Hierarchy • Inheritance • Ordering of Abstractions • Place responsibilities for behaviors at different levels • Subclass shares structures or behaviors of other classes • Eliminates repetitious code and redundancies • Polymorphism • Allows objects of related classes to respond differently to the same message

25. Object-Oriented Development:The Micro Process: Phases • Identify Classes and Objects • Identify Semantics of Classes and Objects • Identify Relationships among Classes and Objects • Implement these Classes and Objects

26. Agendas of the Micro Process To select the right abstractions that model the problem at hand To determine the proper distribution of responsibilities among these abstractions To devise a simple set of mechanisms that regulate these abstractions To concretely represent these abstractions and mechanisms in the most efficient and economical way.

27. Identify Classes and Objects Purpose: • Selected right abstractions to model problem at hand Products • Dictionary of Abstractions Activity: • Discovery and Invention of Abstractions • Examine Vocabulary • Pool wisdom and experience Agents • Project Architect and Abstractionists Milestones and Measures • Reasonable/Achievable Goals

28. Identify Semantics of Classes and Objects Purpose: • Determine proper distribution of responsibilities Products: • A specification of roles and responsibilities of key abstraction • Software the codifies these specifications • Diagrams or similar artifacts that establish meaning Activity: • Scenario Planning • Isolated Class Design • Pattern Scavenging Agents • Project Abstractionists and Application Engineers Milestones and Measures • Sufficiency • Primitiveness • Completeness

29. Identify Relationships Among Classes and Objects Purpose: • Devise set of mechanisms to regulated classes and objects Products: • A specification of relationships among key abstractions • Software that codifies these specifications • Diagrams or similar artifacts that establish meaning of each relationship as well as larger collaborations Activity: • Association specific • Collaboration identification • Association Refinement Agents • Project Abstractionists and Application Engineers Milestones and Measures • Specify semantics and relationships among certain abstractions • Cohesion, Coupling and Completeness

30. Implement Classes and Objects Purpose: • Represent each abstraction and mechanism concretely in most efficient and elegant way Products: • Software the codifies decisions about the representation of classes and mechanisms Activity: • Selection of structures and algorithms that complete the rules and responsibilities of the various abstractions Agents • Application Engineers Milestones and Measures • Identify all interesting abstractions to satisfy the responsibilities of higher-level abstractions identified during micro process • Simplicity

31. The Risks of Object-Oriented Development Risk Analysis • Activity of Evaluating the Technology, Resources, and Object to Capture and Understand Current Risk • Identify Risks • Estimate the Risks • Evaluate the Risks Risk Management • Activity of Defining a Plan for Mitigating Discovered Risks and Implementing the Plan • Risk Plan • Risk Control • Risk Monitoring

32. Risk Management by Phase Inception: • Bracket Project Risk by Building Proof of Concept Elaboration • Common Understanding of System Scope • Establish System Architecture • Design Common Mechanisms Construction: • Refine the Architecture • Risk- Driven Iterations • Continuous Integration Transition: • Facilitate User Acceptance • Measure User Satisfaction

33. Project Risks Resource Risks: • People • Organization • Funding • Time Technical Risks: • Requirements • Size and Scope • Technology • External Dependencies • Reuse • Success Criteria

34. Reuse Architecture Design Code Requirements Data Human Interface Estimates Project Plans Test Plans Documentation

35. Architecture Patterns and Frameworks Payoff Time Reuse Objectives

36. Team Roles and Responsibilities • Supplemental: Supports Activities of Core Developers • Project Manager Management of Project Deliverables • Analyst: Interpret End User Requirements • Integration: Assembles Compatible Versions for Release • Quality Assurance/Assessment: System-Level testing • Test Software Components: Metrics • Documentation: Produce End-User Documentation • Toolsmith: Integrate Software Tools • System Administrator: Manage Physical Computer Resources • Librarian: Manage Repository Core: Responsible for Actual Software Production • Architect: System's Overall Structure • Abstractionist: Manage system’s Microarchitecture • Application Engineer: Implement and Assemble Classes and Mechanisms found in System

37. Team Roles and Responsibilities Peripheral Roles: Represent Consumers of System • Patron: Champions Project • Product Manager: Manages Product Line • End User: Ultimate Client • Tech Support: Manages Post-Delivery Activities

38. Logical View Development View Scenarios Process View Physical View • The logical view to provide a static picture of the primary abstractions and their relationships • the development view to show how the code is organized into subsystems and libraries and the use of commercial off-the-shelf (COTS) software • the process view to show the processes and tasks • the physical view to show the processors, devices, and links in the operational environment • Finally, a scenario view explains how the other four views work together

39. Summary of the Five Views View Chunk Organization Relations Logical Class Category Usage, containment . . . Process Task Process Invocation, messages . . . Development Module Subsystem, Layer Visibility, inclusion Physical Processor Assignment Connection Scenarios Scripts Use Case Extends, uses

40. A Comparison of Phases of the Object-Oriented Systems Development Life

41. A Comparison of Phases of the Object-Oriented Systems Development Life