Information System Development and Programming Languages

(1)

Information System Development

and

(2)

The System Development Life Cycle

What is an

information system (IS)

?

Hardware, software, data, people, and procedures that work

together to produce quality information

Hardware, software, data, people, and procedures that work

together to produce quality information

System—Set of components that interact to achieve common goal

Businesses use many types of systems

(3)

The System Development Life Cycle

What are the phases of the

system development cycle

?

Phase 1. Planning

Phase 2. Analysis

Phase 3. Design

Phase 4. Implementation

Phase 5. Operating, Support, and Security

 _{Review project requests}  _{Prioritize project requests}  Allocate resources

 _{Form project development}

team

 _{Conduct preliminary investigation}  _{Perform detailed analysis activities:}

Study current system

Determine user requirements Recommend solution

 _{Acquire hardware}

and software, if necessary

 _{Develop details of}

system

 _{Develop programs, if necessary}  _{Install and test new system}  Train users

 Perform maintenance activities

(4)

Arrange tasks into phasesphases

(groups of activities)

The System Development Life Cycle

What are guidelines for system development?

Involve usersusers (anyone for whom system is being built)

(5)

The System Development Life Cycle

Who participates

in the system

(6)

The System Development Life Cycle

What is a

systems analyst

?

Responsible for designing

and developing

information system

Users’ primary contact

person

(7)

The System Development Life Cycle

What is the

project team

?

Consists of users, systems analyst, and other IT professionals Formed to work on project from beginning to end

Project leader

(8)

The System Development Life Cycle

What is

project management

?

 _{Process of planning, scheduling, and controlling activities}

during system development cycle

 _{Project leader identifies elements for project}

Required activities

Goal, objectives, and

expectations, collectively

called scope

Goal, objectives, and

expectations, collectively

called scope

Time estimates for each

activity

Time estimates for each

activity

Cost estimates for each

activity

Cost estimates for each

activity

Activities that can take place

at same time

Activities that can take place

at same time

Order of activities

(9)

The System Development Life Cycle

What is a Gantt chart?

 _{Popular tool used to plan and schedule time relationships}

(10)

The System Development Life Cycle

What is

feasibility

?

Measure of how suitable system development will

be to the company

Operational feasibility

Schedule feasibility

Four feasibility tests:

Technical feasibility Economic

(11)

The System Development Life Cycle

What is a Gantt chart?

 _{Popular tool used to plan and schedule time relationships}

(12)

The System Development Life Cycle

What is

documentation

?

Includes reports, diagrams,

programs, and other deliverables

Collection and summarization

of data and information

(13)

The System Development Life Cycle

What are six data and information gathering techniques?

 _{Review documentation}  _Observe

 _{Questionnaire}  _Interview

 _{Joint-application}

design (JAD) session

(14)

The System Development Life Cycle

What are some reasons to create or modify an

information system?

Competition can lead to change

To improve existing system

Outside group may mandate change To correct problem

(15)

The System Development Life Cycle

What is a request for system services?

 _{Formal request for}

new or modified information system

 Also called

(16)

The System Development Life Cycle

What is the

planning phase

?

Begins when steering committee receives project request

Steering

committee—

decision-making

body for the

company

Function of committee:

Review and

approve project

approve project Allocate resourcesAllocate resources

Form project

development team

Prioritize project

(17)

The System Development Life Cycle

What is the

analysis phase

?

Conduct preliminary

investigation, also

called feasibility

study

Perform detailed

analysis

(18)

The System Development Life Cycle

What is the

preliminary investigation

?

 _{Determine exact nature of problem or improvement and}

whether it is worth pursuing

(19)

The System Development Life Cycle

What is detailed analysis?

Sometimes called logical design

2. Determine user’s wants, needs, and requirements

3. Recommend solution

(20)

Presented to

steering

committee, which

decides how

system will be

developed

The System Development Life Cycle

What is the

system proposal

?

Assesses Assesses

feasibility

of each

alternative

solution

Recommends

the most

feasible

solution for the

project

(21)

The System Development Life Cycle

What are possible solutions?

Buy packaged software—prewritten packaged software

software available for purchase Buy packaged softwarepackaged software—prewritten

software available for purchase

Outsource

Outsource—have outside source develop software

Outsource

Outsource—have outside source develop software

Write own custom software—software custom software

developed at user’s request

Write own custom softwarecustom software—software developed at user’s request

Vertical market software—designed for

particular industry

Vertical market software—designed for

particular industry

Horizontal market software—meets needs

of many companies

Horizontal market software—meets needs

(22)

The System Development Life Cycle

What is the

design phase

?

Acquire hardware and software

Develop all details of new or modified information system

(23)

Test and evaluate

vendor proposals

Test and evaluate

vendor proposals

The System Development Life Cycle

What is needed to acquire new hardware and

software?

 _{Identify all hardware and software requirements of new or}

modified system

Solicit vendor

proposals

Solicit vendor

proposals

Make a decision

Identify technical

specifications

Identify technical

specifications

(24)

The System Development Life Cycle

What are three basic documents used to

summarize technical specifications?

Less formal method that uses standard form

Vendor quotes price(s) for listed

product(s)

Vendor selects product(s) that

meet(s) your requirements and then quotes price(s) Identifies

product(s) you want

Request for proposal (RFP)

Request for quotation (RFQ)

(25)

The System Development Life Cycle

What is a

value-added reseller (VAR)

?

 _{Complete system provided by value-added reseller}

 Value-added reseller (VAR)

purchases products from

manufacturer and then resells them, offering additional

services with product

(26)

The System Development Life Cycle

How do systems analysts test software products?

 _{References from vendor}

 _{Talk to current users of product}  _{Product demonstrations}

 _{Trial version of software}

(27)

The System Development Life Cycle

What is a detailed design?

Includes several activities

Database design Database

design _{output design}Input and Input and

output design Program _design Program

design

(28)

The System Development Life Cycle

What is a mockup?

(29)

The System Development Life Cycle

What is a layout chart?

 _{Input or output that contains programming-like notations for}

(30)

The System Development Life Cycle

What is a

prototype

?

Working model of proposed system

Beginning a prototype too early may lead to

problems

Beginning a prototype too early may lead to

(31)

The System Development Life Cycle

What is

computer-aided software engineering (CASE)

?

 _{Software tools designed to support activities of system}

(32)

Convert to new system

The System Development Life Cycle

What is the

implementation phase

?

 _{Purpose is to construct, or build, new or modified system and}

then deliver it to users

Train users

Install and test new system

(33)

The System Development Life Cycle

What are the four types of tests performed by

system developers?

Verifies application works with other

Systems test

Integration Test Unit Test

Verifies each individual program works by itself

Verifies all programs in application work

together

Verifies the new system works with actual data

(34)

The System Development Life Cycle

What is

training

?

 _{Showing users exactly how they will use new hardware}

(35)

The System Development Life Cycle

What are conversion strategies?

(36)

The System Development Life Cycle

What is the

operation,

support, and security phase

?

Perform maintenance activities

Monitor system performance

Assess system security

(37)

The System Development Life Cycle

What is a

computer security plan

?

 _{Summarizes in writing all of the safeguards that are in place to}

protect a company’s information assets

For each risk,

identify the

safeguards

that exist

to detect,

prevent, and

recover from a loss

Identify all

security risks

that may

cause an

information

loss

Identify all

information

assets of an

organization

(38)

Programming Languages

What is a

computer program

?

 _{Set of instructions that directs computer to perform tasks}

(39)

Programming Languages

What are low-level languages and high-level languages?

High-level language High-level language

runs only on one type of computer Machine-dependent

runs only on one type of computer Often machine-independent

can run on many different

types of computers and operating systems

Often machine-independent

can run on many different

types of computers and operating systems

Machine

Machine and assembly languages assembly languages

are low-level

Machine

Machine and assembly languagesassembly languages

(40)

Programming Languages

What is

machine language

?

 _{Only language computer}

directly recognizes

 _{Uses a series of binary digits}

(1s and 0s) with a combination of numbers and letters that

(41)

Programming Languages

What is

assembly language

?

 _{Instructions made up of}

symbolic instruction codes, meaningful abbreviations and codes

 _{Source program contains}

(42)

Often called third-generation third-generation language (3GL)

language (3GL)

Programming Languages

What is a

procedural language

?

Uses series of English-like words to write instructions Programmer writes

instructions that tell computer what to

(43)

Programming Languages

What is a compiler?

 _{Program that}

(44)

Programming Languages

What is an

interpreter

?

 _{Program that}

translates and executes one program code

statement at a time

 _{Does not produce}

(45)

Programming Languages

What is

COBOL

?

 _{Designed for business applications}

 _{English-like statements make code easy to read, write, and}

maintain

 _COmmon

(46)

Programming Languages

What is

C

?

 _{Powerful language originally designed to write system}

software

(47)

Programming Languages

What is an object-oriented programming (OOP) language?

Used to implement object-oriented

design

Major benefit is ability to reuse existing

objects

Event-driven

Event-driven— checks for and responds to set of events

Java, C++, C#, and Visual Basic are complete

object-oriented languages

Object is item that contains

data and procedures

that act on data

Event is action to

(48)

Programming Languages

What is

Java

?

 _{Developed by Sun}

Microsystems

 _{Similar to C++ but}

(49)

Programming Languages

What is

C++

?

 _{Includes all elements of C, plus additional features}

for working with object-oriented concepts

 _{Used to develop database and Web applications}

What is C#?

 _{Object-oriented programming language based on C++}

 _{Accepted as a standard for Web applications and XML-based}

(50)

Programming Languages

What is

Visual Studio

?

 _{.NET is set of technologies that allows program to run on Internet}  _{Comprised of}_{Visual Basic}_,_{Visual C++}_,_{Visual C#}_,_{and Visual J#}

Step 1. The developer designs the user interface.

Step 2. The developer assigns properties to each object on the form.

Step 3. The developer

(51)

Programming Languages

What is

Delphi

?

 _{Powerful visual programming tool}

 _{Ideal for large-scale enterprise and Web applications}

What is

PowerBuilder

?

 _{Another powerful visual programming tool}  _{Best suited for Web-based and large-scale}

(52)

Programming Languages

What is a

visual programming language

?

Visual programming environment (VPE)

allows developers to drag and drop objects

to build programs

Examples include Alice,

Mindscript and Prograph

Provides visual or

graphical interface for

creating source code

(53)

Programming Languages

What is

RPG

(Report Program Generator)?

 _{Used for generating reports, performing computations, and}

(54)

Programming Languages

What is a fourth-generation language

(

4GL

)

?

 _{Nonprocedural language that allows access to data in database}

 _{Popular 4GL is}_SQL_{, query language that allows users to manage}

(55)

Programming Languages

What are other available programming languages?

ALGOL

ADA APLAPLAPL_APL

BASIC BASIC BASIC

BASIC FORTHFORTHFORTH_FORTH FORTRANFORTRANFORTRAN_FORTRAN HYPERTALKHYPERTALKHYPERTALK_HYPERTALK

LISP LISP LISP

LISP LOGOLOGOLOGO_LOGO MODULA-2MODULA-2MODULA-2_MODULA-2

PASCAL PASCAL PASCAL

(56)

Programming Languages

What is an

application generator

?

 _{Program that creates source code or machine code from}

specification

 _{Consists of report writer, form, and menu generator}

(57)

Programming Languages

What is

HTML

(Hypertext Markup Language)?

(58)

Programming Languages

What is a scripting language?

 _{Typically easy to learn and use}

 JavaScript

 Perl (Practical Extraction and Report Language)

 PHP (PHP: Hypertext Processor)

 Rexx (Restructured eXtended eXecutor)

 Tcl (Tool Command Language)

(59)

Programming Languages

What is

dynamic HTML (DHTML)

?

 _{Allows developers to}

include more graphical

(60)

Programming Languages

What are

XHTML

,

XML

, and

WML

?

XHTML XHTML

(Extensible HTML) (Extensible HTML)

enables Web sites to be displayed more easily on microbrowsers

XML XML

(Extensible Markup Language) (Extensible Markup Language)

allows developers to create customized tags

WML WML

(Wireless Markup Language)

Includes features of HTML and XML

Many PDAs and smart Server sends entire record to

client, enabling client to do much of processing without

going back to server

(61)

Programming Languages

What is

Ajax

?

 _{Stands for Asynchronous JavaScript and XML}

 _{Method of creating interactive Web applications designed to}

provide immediate response

(62)

Programming Languages

What is

Ruby on Rails

(RoR)?

 _{Also called Rails}

 _{Open source framework that provides technologies for developing}

object-oriented, database-driven Web sites

 _{Ruby is derived from a variety of languages, including Ada, LISP,}

(63)

Flash

Expression

Web

Programming Languages

What is

Web page authoring software

?

 _{Creates sophisticated Web pages without using HTML}  _{Generates HTML}

Dreamweaver

(64)

Programming Languages

What is

multimedia authoring software

?

 _{Combines text, graphics,}

animation, audio, and video into interactive presentation

 _{Used for computer-based}

training (CBT) and Web-based training (WBT)

 _{Software includes}

(65)

The Program Development Cycle

What is the

program development cycle

?

 _{Steps programmers use to build computer programs}

 Programming team

—Group of programmers

(66)

The Program Development Cycle

What is a

sequence control structure

?

 _{Control structure that shows actions following each other in}

order

(67)

The Program Development Cycle

What is a

selection control structure

?



_{Tells program which}

action to take, based on

a certain condition



_{Two types}

 Case control structure

 If-then-else control

(68)

The Program Development Cycle

(69)

The Program Development Cycle

What is a

repetition control structure

?

 _{Enables program to perform one or more actions repeatedly}

 Do-while control

structure—repeats as long as condition is true

 Do-until control