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Continuation From Chapter From Chapter 1
Two Types of Approaches
Data Oriented Approach
Process Oriented Approach
PayrollProcessing
System
ProjectManagement
System
TaxData
ProjectData
PersonnelData
PersonnelData
Process-Oriented Approach
PayrollProcessing
System
ProjectManagement
System
TaxData
ProjectData
PersonnelData
Data-Oriented Approach
Database and Application Independence
Database Shared collection of logically related data Centrally managed Designed around subjects
Customers Suppliers
Application Independence Separation of data and definition of data
from applications
Key Differences Between Process- and Data-oriented Approaches
Characteristic Process-Orientation
Data-Orientation
Design focus What thesystem issupposed to doand when
The data thesystem needs tooperate
Key Differences Between Process- and Data-oriented approaches
Characteristic Process-Orientation
Data-Orientation
System stability Limited, asbusinessprocesses andthe applicationsthat supportthem changeconstantly
More enduring,as the dataneeds of anorganization donot changerapidly
Orientation
Key Differences Between Process- and Data-oriented approaches
Characteristic Process-Orientation
Data-Orientation
Dataorganization
Data filesdesigned foreach individualApplication(loosely coupled)
Data filesdesigned forthe enterprise(integrated)
Key Differences Between Process- and Data-oriented approaches
Characteristic Process-Orientation
Data-Orientation
Data stored Too much,uncontrolledduplication
Limited,controlledduplication
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Deliverable 1Project Proposal
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Deliverable 2Require. Analysis
(Pre-ERD)
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Deliverable 3New System Design
(ERD/DFD)
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Deliverable 4 DB Prototype
Systems Development Life Cycle (SDLC)
Project ID and Selection
Proj. Initiation & Planning
Analysis
Logical Design
Physical Design
Implementation
Maintenance
Deliverable 5Final System &
Report
Different Techniques to Improving Information Systems Development
Prototyping Building a scaled-down working version of the
system Advantages: users are involved in design, and
captures requirements in concrete form
Rapid Application Development (RAD) Utilizes prototyping to delay producing system
design until after user requirements are clear
Joint Application Design (JAD) Users, Managers and Analysts work together for
several days Structured meeting to review system requirements
Systems analysts
Key individuals in the systems development process
Systems Analysts perform analysis and design based upon: Understanding of organization’s objectives,
structure and processes Knowledge of how to exploit information
technology for advantage
Chapter 2
Succeeding as a Systems Analyst
Learning Objectives
Discuss analytical skills Describe technical skills Discuss management skills Discuss interpersonal skills Describe systems analysis profession
2.192.19
Analytical Skills for Systems Analysis
Four Sets of Analytical Skills Systems Thinking Organizational Knowledge Problem Identification Problem Solving
2.202.20
Systems Thinking
System A system is an interrelated set of business
procedures used within one business unit working together for a purpose
A system has nine characteristics A system exists within an environment A boundary separates a system from its
environment
2.212.21
Characteristics of a System
Components Interrelated Components Boundary Purpose Environment Interfaces Input Output Constraints
2.222.22
Important System Concepts Decomposition Modularity Coupling Cohesion Logical System Description Physical System Description
2.232.23
Decomposition
The process of breaking down a system into smaller components
ModularityProcess of dividing a system into modules of a relatively uniform size
2.252.25
Coupling
Subsystems that are dependent upon each other are coupled
Cohesion
Extent to which a subsystem performs a single function
Logical System Description
Portrays the purpose and function of the system
2.282.28
Physical System Description
Focuses on how the system will be materially constructed
Systems Thinking -Benefits
ST leads to abstractionabstraction leads to essential characteristics Leads to insights into specific system to question assumptions, provide documentation and manipulate the system without disrupting the real situation
2.302.30
Systems Thinking in Information systems
Information systems are subsystems in larger organizational systems
Data flow diagrams represent information systems as systems
Inputs Outputs System boundaries Environment Subsystems Interrelationship
2.312.31
Problem Identification
Problem: Difference between an existing situation and a desired situationIdentification is process of defining differencesDifferences are defined by comparing the current situation to the output of a model that predicts what the output should be
2.322.32
Problem Analyzing and Solving
Four Phases Intelligence
All relevant information is collected Design
Alternatives are formulated Choice
Best alternative solution is chosen Implementation
Solution is put into practice
2.332.33
Technical Skills for Systems Analysis
Constant re-education is necessary as technology changes rapidly
Activities to keep skills up-to-date
Understanding of a wide variety of technologies is required
2.342.34
Management Skills for Systems Analysis
Four categories Resource Management Project Management Risk Management Change Management
2.352.35
Interpersonal Skills for Systems Analysis
Four types of skills: Communication skills Working alone and with a team Facilitating groups Managing expectations
2.362.36
Communication Skills
Three types used by Systems Analyst Interviewing and Listening Questionnaires Written and Oral Presentation
2.372.37
Facilitating Groups
Involves guiding a group without being a part of the group
Useful skill for sessions such as Joint Application Development (JAD)
Figure 2-9 lists guidelines for running a successful meeting
2.382.38
Systems Analysis as a Profession
Standards have been established for education, training, certification and practice
Several aspects: Standards of Practice Ethics Career Path
2.392.39
Standards of Practice
Development of a Common Language Common programming languages Common modeling languages, such as
Unified Modeling Language (UML)
Career Paths
Consulting
Information Systems within a large corporation
Software vendors
Other opportunities outside of systems analysis
2.412.41