Approaches to Systems Development Week 2 CMIS570

Tonight SDLC Other approaches CASE tools

Why study SA&D? “meat” of the IS function Winchester house example Art vs. Science Methodologies Comprehensive, multiple-step approaches to systems development Models Representation of system, organization, etc. Techniques Particular processes used when following methodology Tools Computer programs which aid development process

Methodologies Rationale Defined stages allow for project control Problems are easier and cheaper to fix earlier in the process

SDLC Systems Development Life Cycle Traditional methodology used to develop, maintain, and replace information systems. Orderly set of activities conducted and planned for each development project.

Steps in SDLC Planning Analysis Design Implementation Support

SDLC Project Planning Analysis Design Implementation Support

Requirements of SDLC Can define project boundary You know what you want the system to do and can specify it in detail

Movement away from SDLC – WHY?

Variations we’ll be examining Traditional – SDLC Variations of the SDLC RAD Spiral Approach Prototyping Extreme programming Object Oriented Traditional UP Package Software / ERP

Data versus Process Process-oriented approach Focuses on how and when data are moved and changed Data-oriented approach Focuses on the ideal organization of data rather than on where and how data are used.

Computer-Aided Software Engineering (CASE) Software tools that provide automated support for some portion of the systems development process. Assists system builders in managing the complexities of information system projects and helps assure that high-quality systems are constructed on time and within budget.

Evolution of CASE Art vs. Science Lack of consistency in systems development Predominantly used with PCs Supports wide variety of system development activities

CASE tools Diagramming tools Analysis tools Tools that enable automatic checking for incomplete, inconsistent, or incorrect specifications in diagrams, forms, and reports Central repository / Data dictionary Repository of all data definitions for all organizational applications Documentation generators Code generators

Tools we have available VISIO Oracle

Next Week Homework #1 DUE: Problem statement for your application Read Chapter 3 Read Appendix A