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


Models


Representation of system, organization, etc.
Techniques


Comprehensive, multiple-step approaches to systems
development
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





Object Oriented



RAD
Spiral Approach
Prototyping
Extreme programming
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


Central repository / Data dictionary



Tools that enable automatic checking for
incomplete, inconsistent, or incorrect
specifications in diagrams, forms, and reports
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