Transcript 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
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
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
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, communication 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.
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 3 / 24
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
DBMS
operations on the data
requested by numerous
users.
Users/Programmers
Application Programs/Queries
Software to process queries/programs
Software to access stored data
Stored database
Definition
(Meta-data)
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Stored database
Chapter 8: Page 4 / 24
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
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 5 / 24
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

...
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 6 / 24
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.
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 7 / 24
Management Information Systems
 Management information systems, sometimes called
information reporting systems, evolved from transaction
processing systems.
 A MIS is a set of software tools
每季淨利
that enables manager to gather,
1400000
1200000
organize, and evaluate informa金額
tion about a workgroup, a depart-
收入
1000000
ment, or an entire organization.
成本
800000
淨利
600000
400000
200000
0
第一季
第二季
第三季
第四季
季別
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 8 / 24
Decision Support Systems
 Decision support systems are a class of computerized
information systems that support decision making activities.
Government
Customers
and suppliers
Competition and
global market
External data sources
Interaction
Decision support system
Manager or
staff specialist
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Query, model, and
analysis results
Chapter 8: Page 9 / 24
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.
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 10 / 24
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)
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 11 / 24
Geographic Information Systems
 A geographic information system (GIS) is a computer
system for capturing, storing, checking, integrating,
manipulating, analyzing and displaying data related to
positions on the Earth's surface.
 Typically, a GIS is used for handling maps of one kind or
another. These might be represented as several different
layers 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.
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 12 / 24
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
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 13 / 24
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.
Preliminary
investigation
System
maintenance
System
analysis
System
implementation
System
design
System
acquisition
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 14 / 24
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?
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 15 / 24
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?
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 16 / 24
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.
Requirements
Identify
user
requirement
Feedback
Develop
initial
prototype
Implement
and use
prototype
Initial prototype
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Refine and
enhance
prototype
Improved
prototype
Chapter 8: Page 17 / 24
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.
Applications or users
DBMS
Operating system
Hardware
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 18 / 24
Database Environment
Users
DBMS
Retrieval/
update
facility
Programming
language
facility
Application
programs
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Database
Utility
programs
Chapter 8: Page 19 / 24
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




國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Higher cost of software.
New hardware.
Higher training costs.
Increased vulnerability.
Chapter 8: Page 20 / 24
Relational DBMS
 In a relational DBMS (RDBMS), the data items and the relationships among
them are organized into tables:




學
生
資
料
表
格
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
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
國
文
成
績
表
格
座號 國文成績
1
85
2
90
3
60
Chapter 8: Page 21 / 24
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 = 2
SELECT 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)
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 22 / 24
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
Web 資料庫應用
線上範例
 The most common applications involve client-server database transactions,
where the user’s browser is the client software.
User
Web server
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Database
server
Chapter 8: Page 23 / 24
Commonly Used DBMS
 Proprietary software







Oracle - Oracle
Sybase - Sybase
DB2 - IBM
Informix - IBM
Microsoft SQL Server
Microsoft Access
...
 Freeware



MySQL
PostgreSQL
...
國立聯合大學電子工程學系 – 計算機概論 – 蕭裕弘
Chapter 8: Page 24 / 24