Accelerated Systems Analysis Approaches

Module Overview

  • System analysis is a crucial project phase for understanding the existing business system, its problems, improvement objectives, and detailed business requirements.

Module Learning Objectives

  • Define systems analysis and its relation to scope definition, problem analysis, requirements analysis, logical design, and decision analysis.

  • Describe systems analysis approaches for solving business system problems.

  • Describe each phase (scope definition, problem analysis, etc.) in terms of:

    • Information system building blocks

    • Purpose, participants, inputs, outputs, techniques, and steps

  • Identify textbook chapters for specific systems analysis tools and techniques.

Learning Contents: Introduction to System Analysis

  • Systems analysis encompasses the early phases of systems development.

  • It involves studying a system and its components, prerequisite to system design.

  • Driven by business concerns of SYSTEM OWNERS and SYSTEM USERS.

  • Addresses KNOWLEDGE, PROCESS, and COMMUNICATIONS building blocks from SYSTEM OWNERS and SYSTEM USER’s perspectives.

  • SYSTEMS ANALYSTS facilitate systems analysis.

  • Documentation and deliverables are stored in a repository (network directory, CASE tool dictionaries, printed documentation, intranet).

Systems Analysis Approaches

  • Fundamentally about problem-solving.

  • Many approaches exist, often viewed as competing but can be complementary.

Model-Driven Analysis Approaches

  • Emphasizes pictorial system models to document and validate systems.

  • The system model becomes the blueprint for designing an improved system.

  • Examples: Structured analysis, information engineering, object-oriented analysis.

  • Uses pictures to communicate business problems, requirements, and solutions.

  • Examples of models: flowcharts, structure charts, organization charts.

  • Often enhanced by automated tools like Microsoft Visio, System Architect, or Rational ROSE.

  • CASE tools offer consistency and completeness.

Traditional Approaches

  • Developed starting in the 1970s.

  • Structured analysis focuses on the flow of data through business and software processes (process-centered).

  • Uses data flow diagrams (Figure 2) to depict processes, inputs, outputs, and data stores.

Information Engineering (IE)

  • Focuses on the structure of stored data (data-centered).

  • Emphasizes analysis of KNOWLEDGE (or data) requirements.

  • Uses entity-relationship diagrams (Figure 3) to model data requirements.

Object-Oriented Approach

  • Views systems as collections of objects encapsulating data and processes.

  • Objects contain data attributes, accessed only through embedded processes (methods).

  • Object-oriented programming languages: Java, C++, .NET.

  • Uses Unified Modeling Language (UML) for modeling.

  • UML includes object class diagrams (Figure 4).

Accelerated Systems Analysis Approaches

  • Emphasize prototype construction for rapid identification of business and user requirements.

  • Prototypes are working but incomplete samples of the desired system.

  • Cater to the “I’ll know what I want when I see it” mentality.

  • Prototypes lack error checking, input data validation, security, and processing completeness.

Discovery Prototyping

  • Uses rapid development technology to help users discover their requirements.

  • Analysts use tools like Microsoft Access to quickly create databases, forms, and reports.

  • Aims to solicit user feedback on whether prototypes represent requirements.

  • The final system is typically developed in a more sophisticated tool.

  • Discourages premature focus on the final