INTRODUCTION TO SYSTEMS ANALYSIS AND DESIGN
his chapter introduces the systems development life cycle, the fundamental fourphase model (planning, analysis, design, and implementation) that is common to all information system development projects. It then examines several commonly used system development methodologies that differ in their focus and approach to each of these phases. The chapter closes with a discussion of the skills and roles needed within the project team.
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Understand the fundamental systems development life cycle and its four phases. Understand several different categories of system development methodologies and how to choose among them. Be familiar with the different skills and roles required on the project team.
Introduction The Systems Development Life Cycle Planning Analysis Design Implementation Systems Development Methodologies Structured Design Rapid Application Development Agile Development Selecting the Appropriate Development Methodology Project Team Skills and Roles Business Analyst Systems Analyst Infrastructure Analyst Change Management Analyst Project Manager Summary
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Chapter 1 Introduction to Systems Analysis and Design
The systems development life cycle (SDLC) is the process of understanding how an information system (IS) can support business needs, designing the system, building it, and delivering it to users. If you have taken a programming class or have programmed on your own, this probably sounds pretty simple. Unfortunately, it is not. A 2004 survey by the Standish Group found that just 28% of IT projects succeed these days. Outright failures—IT projects cancelled before completion—occur in 18% of all IT projects. Unfortunately, many of the systems that aren’t abandoned are delivered to the users signiﬁcantly late, cost far more than planned, and have fewer features than originally planned. Most of us would like to think that these problems only occur to “other” people or “other” organizations, but they happen in most companies. See Figure 1-1 for a sampling of signiﬁcant IT project failures. Even Microsoft has a history of failures and overdue projects (e.g., Windows 1.0, Windows 95).1 Although we would like to promote this book as a “silver bullet” that will keep you from experiencing failed IS projects, we must admit that a silver bullet guaranteeing IS development success does not exist.2 Instead, this book will provide you with several fundamental concepts and many practical techniques that you can use to improve the probability of success. The key person in the SDLC is the systems analyst who analyzes the business situation, identiﬁes opportunities for improvements, and designs an information system to implement them. Being a systems analyst is one of the most interesting, exciting, and challenging jobs around. As a systems analyst, you will work with a variety of people and learn how they conduct business. Speciﬁcally, you will work with a team of systems analysts, programmers, and others on a common mission. You will feel the satisfaction of seeing systems that you designed and developed make a signiﬁcant business impact, while knowing that your unique skills helped make that happen. It is important to remember that the primary objective of the systems analyst is not to create a wonderful system. The primary goal is to create value for the organization, which for most companies means increasing proﬁts (government agencies and not-for-proﬁt organizations measure value differently). Many failed systems were abandoned because the analysts tried to build a wonderful system without clearly understanding how the system would support the organization’s goals, current business processes, and other information systems to provide value. An investment in an information system is like any other...