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Chapter 1
Introduction
Jerry Post
Copyright © 1997
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Purpose of This Class
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S Systems development and programming is hard.
T Many failures in the past and recently.
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Over budget.
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Over schedule.
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Total failure/not completed.
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Teamwork
Large projects require teams of MIS workers.
Need to split project into pieces, coordinate workers.
Need to share and communicate.
Need to control and evaluate progress.
Design characteristics, tips, and tricks.
Planning and scheduling.
Tools.
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Runaway Projects
Technical measures
2 - 5 times over budget
2 - 5 times behind
schedule
Missing technical
objectives
Design problems
Duplication of efforts
Incompatibilities
User/designer conflicts
$
1994
1996
1998
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Project Success and Failure
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Reasons for Success
S Reasons for Failure
Lack of user input
User Involvement
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Incomplete requirements
Executive management
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support
Changing requirements and
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specifications
Clear requirements
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Lack of executive support
Proper planning
Lack of technical skills
Realistic expectations
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Development Trends
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New tools
S Development problems.
Don’t meet deadlines.
Project management
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Go over budget.
Groupware for sharing
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Can’t control large projects.
CASE: Computer-aided
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software engineering
Programmers are
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expensive.
Database management
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You can buy really good
software today.
Transaction processing.
Common applications.
How long does software
last?
Outdated? Functions and
needs change.
Depends on hardware.
systems
Powerful languages (Visual
Basic)
The Internet!
User Interface!
A new way of looking at
development: object-oriented
design
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Business Decisions
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S Information is a valuable resource.
T Information systems are used to
make business decisions.
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Operations
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Tactics
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Strategic
Strategy
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Information Systems
Transaction Processing
Process Control
Decision Support Systems
Expert Systems
Enterprise Information Systems
Mgt.
Tactical
Management
Business Operations
Sharing information
Group Decision Support
Groupware tools
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The Role of the Analyst
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S Analyze and Design Systems
Identify problems, opportunities,
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objectives.
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Analyze information flows.
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Design computerized systems to
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solve problems.
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Problem solving.
Communication.
Change agent.
Control, planning, and structure.
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Systems Development Life Cycle
Feasibility &
Planning
Goals & plans
Systems
Analysis
Proposal
Problems &
Improvements
Business requirements
Systems
Design
Technical Design
Systems
Implementation
New System
Existing System
problems
revisions problems
revisions
Systems Maintenance: Incremental changes
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Design Stages
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Physical Design
S Initiation
Scope
Table definitions
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Feasibility
Application development
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Cost & Time estimates
Data storage
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Security
S Requirements Analysis
User Views & Needs
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Forms
Reports
Processes & Events
Objects & Attributes
Conceptual Design
Models
Data flow diagram
Entity Relationships
Objects
Procedures
Implementation
Training
Purchases
Data conversion
Installation
Evaluation & Review
User feedback
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SDLC Strengths and Weaknesses
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Disadvantages
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Control & targets
Increased costs
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Formality
Increased time
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Financial controls
Hard for DSS
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User input
Requires definitions up front
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Documentation
Testing
Ease of maintenance
Rigid
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Computer Assisted Software Engineering
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CASE tool possibilities
Case complications
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Personal productivity
Expensive
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Diagrams
No standards
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Store & Search
Complex software, learning
Team productivity
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Team must follow methodology.
Sharing up-to-date changes
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CASE Levels
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One shared source of data
Communication
Development
Reverse engineering
Automated programming
Maintenance
Complete records for future
Diagrams and context
Reverse engineering
Upper: front-end
Lower: back-end
CASE tool examples
IEF
Oracle
Designer 2000
Developer 2000
Rational Rose
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