information systems building blocks

1

Information System Building BlocksIntroduction

The chapter will address the following questions: What is the difference between data and information? What is the the product called an information system? What are six classes of information system applications and how

they interoperate? What is the role of information systems architecture in systems

development? What are four groups of stakeholders in information systems

development and the unique role of the systems analyst in relation to the four groups?

Could you be able to recognize categories of systems users and managers who become stakeholders in systems development?

2

Information System Building BlocksIntroduction

The chapter will address the following questions: Can you differentiate between a perspective and a view as it

relates to information systems architecture? What are four perspectives of the DATA focus for an information

system? What are four perspectives of the PROCESS focus for an

information system? What are four perspectives of the INTERFACE focus for an

information system? What are four perspectives of the GEOGRAPHY focus for an

information system?

3

Information System Building BlocksA Review of Fundamentals of

Information Systems

What is the difference between Data and Information? Data are raw facts about the organization and its business

transactions. Most data items have little meaning and use by themselves.

Information is data that has been refined and organized by processing and purposeful intelligence.

Information Systems transform data into useful information.

An information system is an arrangement of people, data, processes, interfaces, and geography that are integrated for the purpose of supporting and improving the day-to-day operations in a business, as well as fulfilling the problem-solving and decision-making information needs of business managers.

4

Information System Building Blocks

Information technology has significantly expanded the power and potential of most information systems.

Information technology is a contemporary term that describes the combination of computer technology (hardware and software) with telecommunications technology (data, image, and voice networks).

A Review of Fundamentals ofInformation Systems

5


Transaction Processing Systems Business transactions are events that serve the mission

of the business. Transaction processing systems are information system

applications that capture and process data about (or for) business transactions. They are sometimes called data processing systems.


6


Management Information Systems Management Information Systems supplement

transaction processing systems with management reports required to plan, monitor, and control business operations. A management information system (MIS) is an information

system application that provides for management-oriented reporting, usually in a predetermined, fixed format.


7


Decision Support Systems Decision Support Systems are concerned with

providing useful information to support the decision process. A decision support system (DSS) is an information system

application that provides its users with decision-oriented information whenever a decision making situation arises. When applied to executive managers, these systems are sometimes called executive information systems.

A DSS is designed to support unstructured decisions.


8


Decision Support Systems A DSS provides one or more of the following types of

support to the decision maker: Identification of problems or decision making opportunities

(similar to exception reporting). Identification of possible solutions or decisions. Access to information needed to solve a problem or make a

decision. Analysis of possible decisions, or of variables that will impact

a decision. Sometimes this is called ‘what if’ analyses. Simulation of possible solutions and their likely results.


9


Decision Support Systems A DSS can utilize a Data Warehouse.

A data warehouse is a read-only, informational database that is populated with detailed, summary, and exception information that can be accessed by end users and managers with DSS tools that generate a virtually limitless variety of information in support of unstructured decisions.


10


Information Systems

Expert Systems Expert Systems are an extension of the decision support

system. An expert system is an information system application that

captures the knowledge and expertise of a problem solver or decision maker, and then simulates the ‘thinking’ of that expert for those who have less expertise.

Expert systems are implemented with artificial intelligence technology, often called expert system shells.

11


Information Systems

Office Information Systems Office Information Systems are concerned with getting

all relevant information to all those who need it. Office information systems support the wide range of

business office activities that provide for improved work flow and communications between workers, regardless of whether or not those workers are physically located in an office.

Office information systems may use the following technologies:

• Electronic forms technology• Work group technology• Electronic messaging technology• Office automation suite technology• Imaging technology

12


Information Systems

Personal and Work Group Information Systems Personal and Work Group Information Systems

typically are built using personal computer technology and software. Personal information systems are those designed to meet the

needs of a single user. They are designed to boost an individual’s productivity.

Work group information systems are those designed to meet the needs of a work group. They are designed to boost the group’s productivity.

13


Transaction Processing

System

Executive Information

System

Management Information

System

Decision Support System

Expert System

Personal Information

System

Office Information

System

Business Database

Expertise Database

Business Data Warehouse

Data

Data

Captured data

Data and

messagesRead-only

data

Data snapshots

Read-only data

Data

Rules

Data

Problem

Decision support

information

Executive inquiry

Executive information

Any Manager

Any Decision Maker

or Executive

Information need

Management information

Any Relevant

User

Problem

Solution

Any User

Transaction Data

Transaction information

Communications between users

and within groups

Any User

Personal data

Shared data

Personal Files &

Databases

Personal data

Personal information

14

Information System Building BlocksA Framework For Information

Systems Architecture

What is an Information Systems Architecture? An information systems architecture provides a unifying

framework into which various people with different perspectives can organize and view the fundamental building blocks of information systems.

Stakeholders have different views of the system and each has something “at stake” in determining the success of the system.

Stakeholders can be broadly classified into four groups: System Owners System Users System Designers System Builders

15

Information System Building BlocksINFORMATION SYSTEMS FRAMEWORK

SYSTEM

ANALYSTS

SYSTEMBUILDERS

SYSTEMDESIGNERS

SYSTEMUSERS

SYSTEMOWNERS

DataTechnology

INFORMATION SYSTEM COMPONENTS(the actual, technical implementation of the system)

INFORMATION SYSTEM DESIGN(HOW the system will be implemented using technology)

INFORMATION SYSTEM REQUIREMENTS(WHAT the system "is" and "must do" independent of technology)

INFORMATION SYSTEM SCOPE(purpose and vision; goals and objectives; costs and benefits)

INFORMATION SYSTEM FOCUSES

NetworkingTechnology

InterfaceTechnology

SoftwareTechnology

16

Information System Building BlocksPerspectives - The People Side of

Information Systems

What are Information Workers? The term information worker (also called knowledge worker)

was coined to describe those people whose jobs involve the creation, collection, processing, distribution, and use of information.

System Owners System owners are an information system's sponsors and chief

advocates. They are usually responsible for budgeting the money and time to develop, operate, and maintain the information system. They are also ultimately responsible for the system’s justification and acceptance.

17


Information Systems

System Users System users are the people who use (and directly benefit from)

the information system on a regular basis – capturing, validating, entering, responding to, storing, and exchanging data and information.

There are many classes of system users including: Internal Users

• Clerical and service workers• Technical and professional staff

– Knowledge workers are a subset of information workers whose responsibilities are based on a specialized body of knowledge.

• Supervisors, middle managers, and executive managers

18


Information Systems

System Users There are many classes of system users including: (continued)

Remote and Mobile Users External Users

19


Information Systems

System Designers System designers translate users' business requirements and

constraints into technical solutions. They design the computer files, databases, inputs, outputs, screens, networks, and programs that will meet the system users' requirements. They also integrate the technical solution back into the day-to-day business environment.

20


Information Systems

System Designers Today’s system designers tend to focus on technical specialties.

Database designers have a DATA focus. Software engineers and programmers have a PROCESS (or

program) focus. Personal computing specialists and systems integrators usually

have an INTERFACE focus. Network and telecommunications specialists have a

GEOGRAPHY focus.

21


Information Systems

System Builders System builders construct the information system components

based upon the design specifications from the system designers. In many cases, the system designer and builder for a component are one and the same.

The applications programmer is the classic example of a system builder.

22


Information Systems

The Role of the System Analyst For the system owners and users, the analyst typically constructs

and validates their views. For the system designers and builders, the analyst (at the very

least) ensures that the technical views are consistent and compatible with the business views.

23

Information System Building BlocksBuilding Blocks - Expanding The Information System Framework

There are at least four distinct focuses in a system. DATA - the raw material used to create useful information. PROCESSES - the activities (including management) that carry

out the mission of the business. INTERFACES - how the system interacts with people and other

systems GEOGRAPHY - where the data is captured and stored; where the

processes happen; where the interfaces happen.

24


SYSTEM

ANALYSTS

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

SystemBuilders'views of

DATA

SystemDesigners'

views ofDATA

SystemUsers'

views ofDATA

SystemOwners'views of

DATA

DATAFOCUS

DataTechnology


PROCESSES

SystemDesigners'

views ofPROCESSES

SystemUsers'

views ofPROCESSES


PROCESSES

PROCESSFOCUS


INTERFACES

SystemDesigners'views of

INTERFACES

SystemUsers'

views ofINTERFACES


INTERFACES

INTERFACEFOCUS


GEOGRAPHY

SystemDesigners'views of

GEOGRAPHY

SystemUsers'view of

GEOGRAPHY


GEOGRAPHY

GEOGRAPHYFOCUS

NetworkingTechnology

InterfaceTechnologySoftware

Technology

25


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

FOCUS ONSYSTEM

DATA

COBOL Program

Structure Chart

Data Flow Diagram

Decomposition Diagram

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

COBOLCompiler

onIBM 3090 MVS

InterfaceTechnology Networking

Telchnology

FOCUS ONSYSTEM

GEOGRAPHY

Marketing

Advertising

Orders

Sales

Cancellations Services

Check credit

Validate cus tomer

Validate produc ts

Release order

Customers

Orders

Produc ts

order

cus tomer number

valid order

order w ithout valid

cus tomer

credit

order w ith valid products

approved order

quantity in stock

approved order

rejec ted order

prices

pick ing ticket

Or der P r ocessing

P rogr am

Pr ocess an Or der

Initiation Routine

S hutdown Routine

Get an Order

Validate an Or der

File an Or der

Check Custom er

Credit

Check Pr oduct

Data

Check Credit Data

Release an

Or der

Custom er s P roducts Order s

VALIDATE_AN_ORDER. REPEAT UNTIL NO_MORE_ORDERS PERFORM CUSTOMER_VALIDATIO REPEAT UNTIL NO_MORE_ORDER PERFORM PRODUCT_VALIDATI END REPEAT. PERFORM CREDIT_CHECK. IF CREDIT_CHECK 'BAD' THEN

26


Building Blocks of Data Data is the raw material used to produce information. Goal is to capture and store business data using database

technology.

27


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Programs

Database Schema

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

SoftwareTechnology


Telchnology

FOCUS ONSYSTEM

GEOGRAPHY

Customers order zero, one, or more products. Products may be ordered by zero, one, or more customers.

CUSTOMER customer_no [Alpha (10)] INDEX customer_name [Alpha(32)] customer_rating [Alpha(1)] INDEX balance_due [Real(5,2)]

PRODUCT product_no [Alpha(10)] INDEX product_name [Alpha(32)] unit_of_measure [Alpha(2)] unit_price [Real(3,2)] quantity_available [Integer(4)]

ORDER order_no [Alpha(12)] INDEX order_date [Date(mmddyyyy) CUSTOMER.customer_no

ORDER_PRODUCT ORDER.order_no PRODUCT.product_no quantity_ordered [Integer(2)

CREATE TABLE CUSTOMER (customer_no CHAR(10) NOT NULL customer_name CHAR(32) NOT NULL customer _rating CHAR(1) NOT NULL balance_due DECIMAL(5,2) CREATE INDEX cust_no_idx on CUSTOMER CREATE INDEX cust_rt_idx on CUSTOMER

CUSTOMER customer-no customer-name customer-rating balance-due

PRODUCT product-no product-name unit-of-measure unit-price quantity-available

ORDER order-no order-date products-ordered quantities-ordered

28


Building Blocks of Data System Owners’ View of Data

They are interested in business resources.• Business resources are (1) things that are essential to the system's

purpose or mission; or (2) things that must be managed or controlled in order to achieve business goals and objectives.

29


Building Blocks of Data System Users’ View of Data

They are experts about the data that describe the business system.

Only see data in how it is currently implemented or think it should be implemented.

They relate data requirements to systems analysts.• Data requirements are a representation of users' data in terms of

entities, attributes, relationships, and rules. Data requirements should be expressed in a format that is independent of the technology that can or will be used to implement the data.

30


Building Blocks of Data System Designers’ View of Data

System designers translate requirements into computer files and databases.

System designers’ view of data consists of data structures, database schemas, file organizations, fields, indexes, and other technology-dependent components.

System designers’ view of data as shown in the data column of the framework is a database schema.

31


Building Blocks of Data System Builders’ View of Data:

System builders are closest to the database technology foundation.

System builders are forced to represent data in very precise and unforgiving languages. • The most commonly encountered database

construction language is SQL (Structured Query Language).

32


Building Blocks of Processes PROCESSES deliver the functionality of an information system. Processes perform the work in a system. The goal is to automate appropriate processes with software

technology.

33


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA

Application Programs

Application Schema

Business Process Reqts.

Business Functions

FOCUS ONSYSTEM

PROCESSES

FOCUS ON SYSTEM

INTERFACES

Software(and Hardware)

Technology


Telchnology

FOCUS ONSYSTEM

GEOGRAPHY

Marketing

Advertising

Orders

Sales


Order Pr ocessing

Program

Process an Order

Initiation Routine

Shutdown Routine

Get an Order

Validate an Order

File an Order

Check Customer

Credit

Check Product

Data

Check Credit Data

Release an

Order

Customers Products Orders


Check credit

Validate customer

Validate produc ts

Release order

Customers

Orders

Products

order

customer number

valid order

order w ithout valid

customer

credit

order with valid products

approved order

quantity in stock

approved order

rejec ted order

pr ices

picking ticket

34


Building Blocks of Processes System Owners’ View of Processes

System owners are interested in the groups of high-level processes called business functions.

• Business functions are ongoing activities that support the business. Functions can be decomposed into other functions, and eventually, into discrete processes that do specific tasks.

Historically, most information systems were (or are) function-centered. That meant that the system supported one business function or functional area.

35


Building Blocks of Processes System Owners’ View of Processes (continued)

Today, many single-function information systems are being redesigned as cross-functional systems.

• A cross functional information system supports relevant business processes from several business functions without regard to traditional organizational boundaries such as divisions, departments, centers, and offices.

This trend is being driven by total quality management and business process redesign initiatives that are intended to reinvent and streamline the way organizations do business

36


Building Blocks of Processes System Users’ View of Processes

Users see processes in terms of discrete business processes.• Business processes are discrete activities that have inputs and

outputs, as well as starting times and stopping times. Some business processes happen repetitively, while others happen occasionally, or even rarely. Business processes may be implemented by people, machines, computers, or a combination of all three.

• Specific policies and procedures underlie these business processes.– Policies are a set of rules that apply to a business process.– Procedures are step-by-step instructions and logic for

accomplishing a business process.

37


Building Blocks of Processes System Designers’ View of Processes

Is constrained by the limitations of specific technology. Choice(s) may be limited by a standardized application

architecture that specifies which software (and hardware) technologies must be used.

The designers’ view of processes is technical. The designer tends to focus on an application schema.

• An application schema is a model that communicates how selected business processes are, or will be, implemented using the computer and programs.

38


Building Blocks of Processes System Builders’ View of Processes

System builders represent PROCESSES using precise computer programming languages that describe inputs, outputs, logic, and control.

Computer programming languages are used to write applications programs.

• Applications programs are language-based, machine-readable representations of what a computer process is supposed to do, or how a computer process is supposed to accomplish its task.

39


Building Blocks of Processes System Builders’ View of Processes (continued)

Some computer programming languages provide an excellent environment for prototyping computer processes.

• Prototyping is a technique for quickly building a functioning model of the information system using rapid application development tools (provided with most popular programming languages).

40


Building Blocks of Interfaces There are two critical components to information system

Interfaces. Information systems must provide effective and efficient

interfaces to the system’s users. Information systems must interface effectively and efficiently

to other information systems, both within the business, and increasingly with other businesses’ information systems.

Technologies exist to implement interfaces. Technologies exist that can almost completely eliminate human

error or intervention. Technologies exist for system integration.

41


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA


Application Schema


Business Functions

FOCUS ONSYSTEM

PROCESSES

Component Programs

Interface Schema

Input/Output Reqts.

System Context

FOCUS ON SYSTEM

INTERFACES


Technology


Telchnology

FOCUS ONSYSTEM

GEOGRAPHY

Order Management

SystemCustomer

Accounts Receivable Database

War ehouse

Bank

Order Picking Order

Credit

Credit Voucher

Order Form

H elp +

Customer Form

Product Lookup

Logon

New Customer

N ew Order

Order Accept edChange

of Address

First Order

Request Order Help

Order Help Complete

Request Product Lookup

Request Product Lookup H elp

Product Lookup Help Complete

On Event Help.ButtonClick Do Change Focus HelpDialog On Event OKButton Do Begin {proecdure} End On Event CancelButton Do

F ire c ra c k e r Sa le s

42


Building Blocks of Interfaces System Owners’ View of Interfaces

System owners are concerned with costs and benefits of the interfacing solutions that will be developed.

When considering whether or not to sponsor a new information system, the system owners only want to know:

• With which business units, customers, and external businesses will the new system interface?

• What are the key inputs and outputs with respect to those business units, customers, and external businesses?

• Will the system have to interface with any other information systems or services?

• Are there any corporate or governmental regulations or policies that may constrain the system interfaces?

43


Building Blocks of Interfaces System Users’ View of Interfaces

System users are most interested in what has come be called the user interface to the system.

• The user interface defines how the system users directly interact with the information system to provide inputs and queries, and receive outputs and help.

The explosive growth of personal computers, combined with the popularity of graphical user environments such as Microsoft Windows (for Intel-based PCs) and Apple Macintosh (for Motorola-based PCs) has created a defacto standard – the graphical user interface.

44


Building Blocks of Interfaces System Designers’ View of Interfaces

System designers must be concerned the details of both user and system interfaces.

System designers are concerned with consistency, completeness, and user dialogues of user interfaces.

• User dialogues describe how the user moves from screen-to-screen, interacting with the application programs to perform useful work.

System designers view the interface in terms of interface properties, system states, events that change the system states, and responses to events.

• Collectively, this is called the interface schema.

45


Building Blocks of Interfaces System Designers’ View of Interfaces (continued)

System designers are concerned with system-to-system interfaces.

System designers have to design the system-to-system interfaces that allow a new information system to transparently interoperate with previously designed systems.

46


Building Blocks of Interfaces System Builders’ View of Interfaces

System builders construct, install, test, and implement both user and system interfaces.

• For user interfaces, the technology is usually embedded into the programming language environments used to construct the computer processes.

• System interfaces are considerably more complex to construct and may utilize system interfacing technologies such as middleware.– Middleware is a layer of utility software that sits in between

applications software and systems software to transparently integrate differing technologies so that they can operate.

47


Building Blocks of Geography Information systems geography describes:

the distribution of DATA, PROCESSES, and INTERFACES (the other building blocks) to appropriate business locations

the movement of data and information between those locations The inclusion of GEOGRAPHY in the framework is driven by the

trend towards distributed computing. Distributed computing is the decentralization of applications

and databases to multiple computers across a computer network.

48


Building Blocks of Geography The most popular application of distributed computing is called

client/server computing. In a client/server computing application, information system

building blocks are distributed between ‘client’ personal computers and ‘server’ shared computers. The clients and servers effectively interoperate to share the overall workload.

49


Building Blocks of Geography Distributed computing is being driven by several trends.

Organizations that can gain faster access to critical information have a competitive advantage.

Organizations that can extend their information systems to include their customers and suppliers have a competitive advantage.

Organizations operate in more locations, national and international, then ever before.

50


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

Database Scehma

Data Requirements

Business Subjects

FOCUS ONSYSTEM

DATA


Application Schema


Business Functions

FOCUS ONSYSTEM

PROCESSES

Component Programs

Interface Schema

Input/Output Reqts.

System Context

FOCUS ON SYSTEM

INTERFACES


Technology


Telchnology

Network Programs

Network Schema

Communication Reqts.

Operating Locations

FOCUS ONSYSTEM

GEOGRAPHY

EDI Cust

St. Louis

HQ

LA Office

Indy Ware- house

NY Off ice

West Customers

East Customers

Maintenance Records

Products Cata logorder catalog

changes

ship order

ship order ship order

credit credit

service

St. Louis Mainframe

Indy AIX Server

NT Server LA

NT Server NY

Communications Controlle r

PBX

Enternet LAN A IX/Lan Manager

Ethernet LAN/NT

Ethernet LAN/N T

Client PC Client PC

Client PC Client PC

Create AccountType = SalesClerk Set OrderDir.Rights=full Set CustomerDir.Rights=full Set ProductDir.Rights=read Set OrderAppDir.Rights=copy

51


Building Blocks - Expanding The Information System Framework

Building Blocks of Geography System Owners’ View of Geography

The system owner views the geography in terms of operating locations.

The system owners will ultimately decide the degree to which the system will be centralized, distributed, or duplicated.

52



Building Blocks of Geography System Users’ View of Geography

System users are the experts about the requirements for any given location.

System users are interested in operating locations. System users tend to have a more microscopic view of

locations. System users think in terms of communications requirements.

• Communications requirements define the information resource requirements for operating locations, and how different operating locations need to communicate with one another. These communication requirements are expressed independent of any specific technology is or can be used to implement them.

53



Building Blocks of Geography System Designers’ View of Geography

System designer's view of GEOGRAPHY is influenced and/or constrained by the limitations of specific technology.

System designer's view of GEOGRAPHY is depicted via a network schema that can support the business network.

• A network schema (also called a network configuration or topology) is a technical model that identifies all of the computing centers, computers, and networking hardware that will be involved in a computer application.

System designer's view of networks is technical.

54



Building Blocks of Geography System Designers’ View of Geography (continued)

Given the network schematic, the designer’s job is to determine the optimal distribution of DATA, PROCESSES, and INTERFACES across the network.

• This is called application partitioning. The system designer's intent is to prepare specifications that:

• fulfill the business network requirements of the users• provide sufficient detail and consistency for communicating the

network design to the system builders.

55



Building Blocks of Geography System Builders’ View of Geography

System builders use telecommunications languages and standards to write network programs.

• Network programs are machine-readable specifications of computer communications parameters such as node addresses, protocols, line speeds, flow controls, security, privileges, and other complex, networking parameters.

56


SYSTEM

ANALYSTS

(facilitation)

SYSTEMBUILDERS

(components)

SYSTEMDESIGNERS

(specification)

SYSTEMUSERS

(requirements)

SYSTEMOWNERS

(scope)

DatabaseTechnology

Database Structures

any good DB course

Database Scehma

Chapter 12

Data Requirements

Chapters 5, 6

Business Subjects

Chapters 5, 6

FOCUS ONSYSTEM

DATA


any good programming course

Application Schema

Chapters 11, 16

Business Processes

Chapters 5, 7

Business Functions

Chapters 5, 7

FOCUS ONSYSTEM

PROCESSES

Component Programs

any good programming course

Interface Schema

Chapters 11, 13, 14, 15

Interface Requirements

Chapters 5, 13, 14

System Context

Chapters 5, 7

FOCUS ON SYSTEM

INTERFACES


Technology


Telchnology

Network Programs

any good data communication course

Network Schema

Chapter 11

Communication Reqts.

Chapters 5, 8

Operating Locations

Chapters 5, 8

FOCUS ONSYSTEM

GEOGRAPHY

CREATE TABLE CUSTOMER (customer_no CHAR(10) NOT NULL customer_name CHAR(32) NOT NULL customer _rating CHAR(1) NOT NULL balance_due DECIMAL(5,2) CREATE INDEX cust_no_idx on CUSTOMER CREATE INDEX cust_rt_idx on CUSTOMER

CUSTOMER customer-no customer-name customer-rating balance-due

PRODUCT product-no product-name unit-of-measure unit-price quantity-available

ORDER order-no order-date products-ordered quantities-ordered

Order Form

Help +

Customer Form

Product Lookup

Logon

New Customer

New Order

Order AcceptedChange

of Address

First Order

Request Order Help

Order Help Complete

Request Product Lookup

Request Product Lookup Help

Product Lookup Help Complete

On Event Help.ButtonClick Do Change Focus HelpDialog On Event OKButton Do Begin {proecdure} End On Event CancelButton Do

Create AccountType = SalesClerk Set OrderDir.Rights=full Set CustomerDir.Rights=full Set ProductDir.Rights=read Set OrderAppDir.Rights=copy

Customers order zero, one, or more products. Products may be ordered by zero, one, or more customers.

Market ing

Advert ising

Orders

Sales


Or der Managem ent

SystemCustom er

Accounts Receivable Database

War ehouse

Bank

Order P icking Order

Cr edit

Cr edit Voucher

Check credit

Validate customer

Validate products

Release order

Customers

Orders

Products

order

customer number

valid order

order without valid

customer

credit

order with valid products

approved order

quantity in stock

approved order

rejected order

prices

picking ticket

Fir ecracker Sal es

EDI Cust

St. Louis

HQ

LA Office

Indy Ware- house

NY Office

West Customers

East Customers

Maintenance Records

Products Catalogorder catalog

changes

ship order

ship order ship order

credit credit

service

CUST OMER custo mer_no [Alph a (10)] INDEX custo mer_name [Alph a(32)] custo mer_rating [Alpha(1)] INDEX balan ce_due [Real(5,2)]

PRODUCT product_no [Alph a(10)] INDEX product_name [Alpha(32)] unit_o f_measu re [Alp ha(2)] unit_p rice [Real(3,2)] quan tity_availab le [Integer(4)]

ORDER order_n o [Alpha(12)] INDEX order_d ate [Date(mmdd yyyy) CUSTO MER.custo mer_no

ORDER_PRODUCT ORDER.o rder_no PRODUCT.product_no qu antity_ordered [Integer(2)

Order Processing

Program

Process an Order

Initiation Routine

Shutdown Routine

Get an Order

Validate an Order

File an Order

Check Customer

Credit

Check Product

Data

Check Credit Data

Release an

Order

Customers Products Orders

St. Louis Mainfr am e

Indy AIX S er ver

NT Ser ver LA

NT Ser ver NY

Comm unications Contr oller

PBX

Enter net LA N AIX /Lan Manager

Ether net LA N/NT

Ethernet LAN/NT

Client PC Client PC

Client PC Client PC


57


Summary Introduction A Review of Fundamentals of Information

Systems A Framework For Information Systems

Architecture Perspectives - The People Side of

Information Systems Building Blocks - Expanding The

Information System Framework

information systems building blocks

Documents