Chapter 8 Information Systems and Database Management Systems 國立聯合大學電子工程學系蕭裕弘

Chapter 8Information Systems and

Database Management Systems

國立聯合大學　電子工程學系蕭裕弘

國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘 Chapter 8: Page 2 / 24

Chapter Goals

介紹一些企業常用的資訊系統

介紹資訊系統的的開發過程

介紹資料庫管理系統的內涵與

特性

介紹一些資料庫的應用


1. Introduction

An information system is comprised of all the components that collect, manipulate, and disseminate data or information.

It usually includes hardware,

software, people, communica-

tion systems, and the data itself. The activities involved include

inputting data, processing of

data into information, storage

of data and information, and the

production of outputs such as

management reports.


Database Management Systems

A database is an information set with a regular structure. Its front-end allows data access, searching and sorting routines. Its back-end affords data inputting and updating.

A database management system

(DBMS) is a computer program

designed to manage a

database and run

operations on the data

requested by numerous

users.

Users/Programmers

Application Programs/Queries

Software to process queries/programs

Software to access stored data

Stored databaseDefinition

(Meta-data)Stored database

DBMS


2. Types of Information Systems

Office automation systems Transaction processing systems Management information systems (MIS) Decision support systems (DDS) Enterprise resource planning systems Design and manufacturing systems Geographic information systems (GIS) Artificial intelligence systems


Office Automation Systems

These combinations of hardware, software, and other resources used to facilitate communications and enhance productivity are collectively referred to as office automatic systems. Document-processing systems

Paperless office

Communication systems Email Faxing Video conferencing Workgroup computing ...


Transaction Processing Systems

Transaction processing systems are information system applications that capture and process data about business transactions.

Transaction processing is the unambiguous and independent execution of a set of operations on data in a relational database, which treats that set of actions as a single event. If any part of the transaction process fails, the entire transaction fails

and all participating resources are rolled back to their previous state.


Management Information Systems

Management information systems, sometimes called informati

on reporting systems, evolved from transaction processing syst

ems.

A MIS is a set of software tools

that enables manager to gather,

organize, and evaluate informa-

tion about a workgroup, a depart-

ment, or an entire organization.

每季淨利

0

200000

400000

600000

800000

1000000

1200000

1400000

第一季第二季第三季第四季

季別

金額

收入

成本

淨利


Decision Support Systems

Decision support systems are a class of computerized information systems that support decision making activities.

GovernmentCustomers

and suppliersCompetition and

global market

Decision support system

External data sources

Query, model, andanalysis results

Interaction

Manager orstaff specialist


Enterprise Resource Planning Systems

Enterprise resource planning systems (ERP) are management information

systems that integrate and automate many of the business practices

associated with the operations or production aspects of a company.

These typically include manufacturing, logistics, distribution, inventory,

shipping, invoicing, and accounting.

ERP software can aid in the control of

many business activities,

like sales, delivery, billing, production,

inventory management, and

human resource management systems.


Design and Manufacturing Systems

Computers are widely used in organizational systems to improve

productivity at the design stage and at the manufacturing stage.

Computer-aided design (CAD)

Computer-aided manufacturing (CAM)


Geographic Information Systems

A geographic information system (GIS) is a computer syst

em for capturing, storing, checking, integrating, manipulat

ing, analyzing and displaying data related to positions on t

he Earth's surface.

Typically, a GIS is used for handling maps of one kind or

another. These might be represented as several different la

yers where each layer holds data about a particular kind of

feature (e.g. roads). Each feature is linked to a position on

the graphical image of a map.

The global positioning system (GPS), is an intermediate

circular orbit satellite navigation system used for

determining one's precise location and providing a highly

accurate time reference almost anywhere on Earth.


Artificial Intelligence Systems

A computer can perform work at extremely fast speeds. It can also be

programmed with a set of rules or guidelines, thereby enabling it to draw

certain types of conclusions based on the input it receives.

When computer systems combine these two abilities to perform in ways that

would be considered intelligent if observed in humans, it is commonly

referred to as artificial intelligence (AI).

Systems that use artificial intelligence are called artificial intelligence

systems.

Four main types of artificial intelligence systems:

Expert systems

Natural language systems

Neural network systems

Robotics


3. System Development Life Cycle

System development life cycle, or SDLC, is the process of developing

information systems through investigation, analysis, design,

implementation and maintenance.

Preliminaryinvestigation

Systemanalysis

Systemdesign

Systemacquisition

Systemimplementation

Systemmaintenance


Issues to Cover during System Design Stage

Output considerations Who are the system users and what types of information do they need? How often is this information needed? Annually? Monthly? Daily? On demand? What output devices and storage media are necessary to provide the required

information? How should output be formatted or arranged so that it can easily be understood by

users? Input considerations

What data need to be gathered and who will gather them? How often do data need to be gathered? What input devices and media are required for data collection and input?

Storage considerations How will data be accessed and organized? What storage capacity is required? How fast must data be accessed? What storage devices are appropriate?


Issues to Cover during System Design Stage

Processing considerations What type of functionality is required in the software? What type of processing power is required? A mainframe? A minicomputer? A

microcomputer? What special processing environments must be considered? A communication

network? A database processing environment? System controls

What measures must be taken to ensure that data are secure from unauthorized use, theft, and natural disasters?

What measures must be taken to ensure the accuracy and integrity of data going in and information going out?

What measures must be taken to ensure the privacy of individuals represented by the data?

Personnel and procedures What personnel are needed to run the system? What procedures should be followed on the job?


Prototyping

To avoid the potential problem of a system being incompatible with the system user, instead of developing the entire system before users ever lay their hands on it, many system analysts have advocated prototyping.

Identifyuser

requirement

Developinitial

prototype

Implementand use

prototype

Refine andenhance

prototype

Requirements

Initial prototype

Feedback

Improvedprototype


4. What is Database?

A database is a collection of related data that is stored and organized in a manner enabling information to be retrieved from the database as needed.

A database management system (DBMS) can be an extremely complex set of software programs that controls the organization, storage and retrieval of data (fields, records and files) in a database. The DBMS also controls the security and integrity of the database. The DBMS accepts requests for

data from the application program

and instructs the operating system

to transfer the appropriate data.

Hardware

Operating system

DBMS

Applications or users


Database Environment

Users

DBMS

Retrieval/updatefacility

Programminglanguagefacility

Applicationprograms

DatabaseUtility

programs


Adv. and Disadv. of the Database Approach

Advantages Better information. Faster response time. Lower operating cost. Lower storage

requirements. Improved data integrity. Better data

management.

Disadvantages Higher cost of software. New hardware. Higher training costs. Increased vulnerability.


Relational DBMS

In a relational DBMS (RDBMS), the data items and the relationships among them are organized into tables: A table is a collection of records. A record is a collection of related fields. Each field of a database table contains a single data value. Each record in a table contains the same fields.

座號姓名性別

1 王小美女

2 柯南男

3 葉大雄男

座號國文成績

1 85

2 90

3 60

學生資料表格

國文成績表格


Structured Query Language

Structured query language (SQL) is the most popular computer language used with relational databases. Technically, SQL is a declarative programming language.

SELECT 姓名 FROM 學生資料表格SELECT 姓名 FROM 學生資料表格 WHERE 座號 = 2SELECT 姓名 , 國文成績

FROM 學生資料表格 , 國文成績表格WHERE 座號 = 2 ORDER BY 國文成績

INSERT INTO 學生資料表格 VALUES (4, ‘李大同’ , ‘男’ )

INSERT INTO 國文成績表格 VALUES (4, 60)


Databases and the Web

Databases are extremely common on the web.

Examples of web databases in use:

Information retrieval

E-commerce and e-business

Dynamic web pages

The most common applications involve client-server database transactions,

where the user’s browser is the client software.

User Web serverDatabase

server

Web 資料庫應用線上範例


Commonly Used DBMS

Proprietary software Oracle - Oracle Sybase - Sybase DB2 - IBM Informix - IBM Microsoft SQL Server Microsoft Access ...

Freeware MySQL PostgreSQL ...

Documents

Chapter 8 Information Systems and Database Management Systems 國立聯合大學 電子工程學系 蕭裕弘

Chapter 8 Information Systems and Database Management Systems 國立聯合大學電子工程學系蕭裕弘