Download Ch5,6

Chapter 5
Data Resource
Management
授課老師：台大工管系 楊立偉
McGraw-Hill/Irwin
Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved.
Learning Objectives
Provide examples to illustrate each of the
following concepts:
Major types of databases 各種不同的資料庫
Data warehouses and data mining 資料倉儲及資料探勘
Logical data elements 資料庫的組成
Fundamental database structures 基本的資料庫結構
Database development 資料庫的開發
5-2
Section 1
Technical Foundations of Database
Management
5-3
I. Database Management System
Data resources must be structured and
organized in some logical manner so
they can be accessed, processed,
retrieved, and managed easily
5-4
II. Fundamental Data Concepts
Character (and Number, DateTime, Boolean)
Field (or Attribute, Property, Column)
a grouping of related characters, as a last name or
a salary, represents an attribute of some entity
Record (or Row)
a grouping of attributes that describe an entity
File (or Table)
a group of related data records
Database
a collection of logically related data elements
5-5
II. Fundamental Data Concepts
5-6
III. Database Structures (Models)
 Hierarchical Structure – treelike structure of oneto-many parent-child relationships (each child can
have only one parent)
 Network Structure – similar to hierarchical but
allows many-to-many relationships (a child record
can have more than one parent)
 Relational Structure – the most widely used
database model today; data is represented as a
series of two-dimensional tables called Relations;
each column is a named attribute of the entity,
each row is an unnamed instance of that entity
5-7
5-8
人們最習慣的表達方式
亦可呈現階層及網路關係
5-9
III. Database Structures (Models)
Relational Operations
Select – create a subset that meets a criterion 水平
篩選
Project – create a subset of the columns in the
temporary tables 垂直篩選
Join – temporarily combine two or more tables for
comparison 跨表連接
Multidimensional Structure – variation of the
Relational model using multidimensional
structures to organize and express
relationships
5-10
III. Database Structures (Models)
使用附表之外鍵 foreign key of dependent table
至主表之主鍵進行查找 primary key of parent table
5-11
III. Database Structures (Models)
(二維)表格
也可以呈現多維資料
5-12
III. Database Structures (Models)
Object-Oriented Structure 物件導向
combining the data of interest and the processes
that act on that data into a structure called an
object 將資料與允許的操作放在一起 (避免誤用)
Encapsulation – allows complex data types 封裝
(隱藏細節)
Inheritance – allows replication of some/all of the
characteristics of a parent object in the creation of
a child object 繼承 (讓設計變簡單, 不用一直重覆)
5-13
III. Database Structures (Models)
5-14
IV. Database Development
Database Administrator (DBA) – controls
development and administration of the
database 資料庫管理師
Data Definition Language (DDL) – used to
specify the contents, relationships, and
structure of the database 用以定義(設計)資料
庫的語言
5-15
IV. Database Development
Metadata
data about the data 例如書目資料 (描述書籍資料)
Data Dictionary
directory containing the metadata 例如圖書館的
分類目錄 (涵蓋書本、影片、期刊等的metadata)
Data Planning and Database Design
Data Modeling (Entity-Relationship Diagrams) –
logical models of the data itself; this must be done
before choosing the database model
Schema – the physical/internal view of a system
Subschema – the logical/external view of a system
5-16
IV. Database Development
實際到資料庫系統
進行開表配置實作
資料基模 Schema
例如開出一組表格
描述商業邏輯的
需求規格書
資料模型(設計圖)
如E-R model
5-17
IV. Database Development
Entity Relationship Diagram
5-18
Sample E-R Diagram
1
0 or 1
1…N
0…N
5-19
Database Pioneer Rethinks the Best Way
to Organize Data
How do databases currently focus on
data to be stored?
What is suggested as a better away to
focus on data warehouses?
What gains do these changes promise?
Technology of data capturing, storage,
search/retrieve, analysis and applications
5-20
Hadoop: Ready for the Large-scale
Databases of the Future
 What is the strength of Hadoop?
 distributed and scalable
 What does Hadoop do differently from pervious
databases?
 HDFS : Hadoop distributed filesystem
 MapReduce : in a "divide-and-conquer“ way
 Why do we need something different today for
handling data in databases?
 Big data : volume, velocity, variety
 What does this tell you about the future of handling
data?
5-21
Section 2
Managing Data Resources
5-22
I. Data Resource Management
Data are an organizational resource that
must be managed as any other resource
5-23
I. Data Resource Management
Types of Databases Used by
Organizations and End-Users
5-24
II. Types of Databases
Operational Databases – store detailed data to
support business processes and operations
c.f. Informatonal Databases (Data warehouse)
Distributed Databases – many organizations
distribute their databases over multiple
locations
External Databases – outside the firm, free or
fee-based
Hypermedia Databases – hyperlinked pages of
multimedia
5-25
Coty: Using Real-Time Analytics to Track
Demand
What percentage of retails products are
usually out of stock in the U.S.?
What percentage of promotional items
are usually out of stock in the U.S.?
What effect does this have on business?
How does Coty deal with these issues?
5-26
III. Data Warehouses and Data Mining
Data Warehouse – stores data extracted
from other databases
Data Mart – subset of a data warehouse
focusing on a single topic, customer,
product, etc.
Data Mining – analyzing a data
warehouse to reveal hidden patterns
and trends
5-27

Data Warehouse:






A subject-oriented, integrated, time-variant, nonupdatable collection of data used in support of
management decision-making processes
Subject-oriented: e.g. customers, patients, students,
products
Integrated: Consistent naming conventions, formats,
encoding structures; from multiple data sources
Time-variant: Can study trends and changes
Non-updatable: Read-only, periodically refreshed
Data Mart:

A data warehouse that is limited in scope
Ex. Corporate (Data Warehouse) v.s. Department (Data Mart)
Chapter 11

28
III. Data Warehouses and Data Mining
Components of a Data Warehouse System
5-29
III. Data Warehouses and Data Mining
A Data Warehouse and its Data Mart Subsets
5-30
III. Data Warehouses and Data Mining
Data Mining Extracts Business Knowledge
from a Data Warehouse
5-31
IV. Traditional File Processing
Data was stored in independent files without
regard to other needs for that data
Problems of File Processing – databases seek
to solve these problems
1. Data Redundancy – the same data is kept in
more than one location; databases seek to
Control (NOT reduce!) Redundancy; this led to
Data Inconsistency – same data in multiple
locations but the Values were Different
5-32
IV. Traditional File Processing (Cont.)
2. Lack of data Integration – data not easily
available for ad hoc requests
3. Data Dependence – data and programs were
“tightly coupled”, changing one meant having to
change the other
4. Lack of Data Integrity (Standardization) – data
was defined differently by different end users or
applications
5-33
V. Database Management Approach
Consolidate the data from separate files into
databases accessible by multiple application
programs
Database Management System (DBMS) – a
collection of programs to create, maintain, and use
(retrieve) data in a database
Database Maintenance – organizational databases
need to be updated continually
Application Development – facilitated by the Data
Manipulation Language (DML) provided by the
DBMS
5-34
V. Database Management Approach
Database Interrogation – query (“ask”) the
database for information
 Query Language – allows ad hoc requests of the
database
 SQL Queries (Structured Query Language) –
standard query language found in many
databases
 Boolean Logic – 3 logical operators: AND, OR,
and NOT
 Graphical and Natural Queries – easier methods
of structuring SQL statements
5-35
Online Dating: The Technology Behind
Finding Love
Are all dating sites the same? For users,
what makes the difference between
different dating sites?
What is the biggest challenge for
eHarmony?
When is the demand for eHarmony’s
services greatest? Why might this be?
What does this mean from a business
perspective?
5-36
補充 : 大數據如何協助數位行銷 (1)
• 建立資料庫
– 有目標、有主題地、匯整多個資料來源、統整結構與內容
• 協助管理者進行決策
– 了解舊客戶行為，做好客戶關係管理
– 開發新客戶
– 決策支援，選定目標市場與行銷策略
– 降低行銷成本，提高回應率與成交率
– 預測並創造營收、降低成本，提高營運效率
補充 : 大數據如何協助數位行銷 (2)
• 資料探勘 Data mining
– 從大量資料或歷史資料中，透過人工智慧、機器學習等技術，找出
人類難以觀察出、或傳統之統計所無法發現之隱性知識。
– 這些隱性知識包括分布趨勢、決策樹、關聯性、連續性等，對行銷
與客戶關係經營有重大價值。
Ex. Wal-mart 找到尿布與啤酒的關係
7-11的台湾的753感冒指数
• Amazon's Recommendation
– data mining
• to guess
what you would like
based on past records
– collaborative filtering
• "customers who viewed this also viewed…"
案例 : Target
http://www.forbes.com/sites/kashmirhill/2012/02/16/how-target-figured-out-a-teen-girl-was-pregnant-before-her-father-did/
Big Data 的應用方式
運用資料與演算，達成智慧決策
需要快速、大量、各式資料的處理分析能力
Data
Information &
Decisions &
Insights
Actions
• Structured
• Modeling 模型
• Results 結果
• Unstructured
• Deduction 演繹
• Options 選項
• Historic
• Inference 推理
• Prevention 預防
• Prediction 預測
• Suggestion 建議
"turning data into action"
41
近年來的技術突破
語意分析、機器學習、演算法及模型、
計算複雜度及規模、巨量資料
Copyright © Proprietary and Confidential. All rights reserved.
42
Chapter 6
Telecommunications
and Networks
授課老師：台大工管系 楊立偉
McGraw-Hill/Irwin
Copyright © 2013 by The McGraw-Hill Companies, Inc. All rights reserved.
Section 1
Telecommunications and Networks
6-44
I. Networking the Organization
Merging computing and communications
yields computer networks which are
more than the sum of their parts.
6-45
II. The Concept of a Network
The Concept of a Network – an
interconnected/interrelated system
Metcalf’s Law – the utility (use) of a
network equals the square of the number of
users
網路價值以用戶數量的平方的速度增長
a.k.a Network effect 網路效應, Network
Externality 網路外部性
外部性效果：使用者愈多對原來的使用者而言，
不僅其效果不會如一般經濟財（人愈多分享愈
少），反而其效用會愈大
6-46
III. Trends in Telecommunications
6-47
III. Trends in Telecommunications
Telecommunications – the exchange of
information in any form over a network
Industry Trends – massively changed from
government regulated monopolies to a fiercely
competitive markets with many choices
Business Application Trends – all these changes
have caused significant changes in the businesses
use of telecommunications
Internet2 – a high performance network using an
entirely different infrastructure from the public
Internet; used mostly by universities (educational),
research, and government
6-48
III. Trends in Telecommunications
Technology Trends
 Internet Networking Technologies – open systems
with unrestricted connectivity using Internet
networking technologies
 Open Systems – IS using common standards for
h/w, s/w, applications, and networking
 Middleware – programs that mediate between
other programs; an essential part of IT
infrastructure because it joins disparate systems
 Wireless technologies
6-49
IV. The Business Value of
Telecommunications Networks
Cut costs, shorten lead/response times,
improve collaboration, support e-commerce
The Internet Revolution – a “network of networks”,
the largest and most important network, constantly
expanding
Internet Service Providers (ISP) – provides easy
access to the Internet
Internet Applications – browsing the Net, email,
instant messaging
Business Use of the Internet – the Internet adds
value to every prt of the business cycle
The Business Value of the Internet
6-50
6-51
6-52
Telepresence: GE Does Training and
Meetings Face to Face , but Virtually
What is the ultimate competitive advantage?
What did GE want to reduce/eliminate from
meetings and training?
How did participants respond to the meetings?
How would you feel about this type of meeting?
This type of training?
6-53
V. The Role of Intranets
Intranet – a private internal network using
Internet technologies
 The Business Value of Intranets – an enterprise information
portal supporting communications and collaboration
 Communications and Collaboration – improved by Intranets
 Web Publishing – developing and publishing hyperlinked
multimedia documents
 Business Operations and Management – develop/deploy
critical applications supporting operations and managerial
decision making
 Intranet Portal Management – managed by IS/IT professionals
6-54
6-55
Intranet dashboard Revs Up Audi Australia
What was Audi’s problem?
Why was the old portal a problem?
What did they want to do with the portal?
What solution did iD provide?
6-56
VI. The Role of Extranets
Extranet – A private network using Internet
technologies (intranet) opened to select
external entities for purposes of
communications
Purpose – interconnect the business with its
suppliers/customers/business partners
6-57
VI. The Role of Extranets
Extranets connect the internetworked enterprise
to customers, suppliers, and trading partners
6-58
The NFL Scores with New Extranet
According to the case, in 1997 the NFL was the
first major sport league to do what?
By 2008, what had happened? What had
happened in that time?
What solution did the NFL provide?
How does this help the NFL from a business
standpoint?
6-59
Section 2
Telecommunications Network Alternatives
6-60
I. Telecommunications Alternatives
Telecommunications is a highly technical,
rapidly changing field, but most business
professional do not need detailed
knowledge of these details
6-61
II. Telecommunications Network
Model – 5 basic components:
Terminals – any input/output device to
transmit/receive data
Telecommunications Processors – support data
transmission/reception between terminals
Telecommunications Channels – media over which
messages are sent
Computers – interconnected by
telecommunications networks
Telecommunications control software – programs
to control telecommunications activities and
functions
6-62
6-63
III. Types of Telecommunications
Networks
A Network is defined by its geographic area
and who owns the equipment
Wide Area Networks (WAN) – between cities/large
geographic areas, LANs connected by common
carrier or leased lines
Metropolitan Area Networks (MAN) – LANs
connected over a specific geographical area
Local Area Networks (LAN) – equipment owned by
the firm, short distances, usually within a single
building (or room)
6-64
III. Types of Telecommunications
Networks
A LAN allows sharing of resources
6-65
6-66
III. Types of Telecommunications
Networks
Virtual Private Networks (VPN) – a network using
the Internet as a backbone but incorporating
security for privacy
Client/Server Networks – a powerful, central
computer (server) providing information and
processing (services) to multiple end-user
computers (clients)
Network Computing – a minimally-powered
browser-based computer obtains its data and
processing from the Internet
6-67
Wireless VPNs: Alternatives for Secure
Remote Access
What is VPN?
Why is a VPN important to business
travelers today?
What is the challenge of a VPN today?
6-68
6-69
6-70
6-71
III. Types of Telecommunications
Networks
Peer-to-Peer Networks (P2P)
Central Server Architecture – P2P software
connects a PC to the central server with a
directory of all other users (peers)
Pure Peer-to-Peer – PCs connected without any
central server
Every peer communicates with its neighbors, and
then propagate to the network.
6-72
IV. Digital and Analog Signals
Analog (continuous) – any value
between the maximum/minimum value
is possible (e.g., any frequency between
20hz and 20K hz)
Digital (discrete) – only certain values
are permitted (e.g., 0 and 1)
6-73
V. Telecommunications Media
Media – the physical pathway over which signals
travel
Twisted-Pair Wire – pair of very thin copper wires
twisted in opposite directions (noise reduction);
cheap, easy to use, but low bandwidth 雙絞線
Coaxial Cable – central copper wire wrapped with
insulator, an external wire braid surrounded by a
cover; not as easy to manipulate, more expensive
than twisted pair, but higher bandwidth 銅軸電纜
6-74
V. Telecommunications Media
 Fiber Optics – hair-thin glass fibers wrapped in
protective jacket (cladding), conducts light (photons);
difficult to handle, expensive, but highest bandwidth
光纖
 The Problem of “The Last Mile” 最後一哩 – although a
telecomm provider puts the latest technology to your
door, your home/office is still wired with old fashioned
technology, so all the provider’s efforts do not help
once the signal reaches your location and you are
constrained (limited) by the technology in your own
home/office
6-75
6-76
6-77
VI. Wireless Technologies
Wireless Technologies – communications without wires
 Terrestrial Microwave – earth-bound towers and line-of-sight
radio signals, towers placed on hills and tops of building
 Communications Satellites – also use microwaves, satellites in
geosynchronous orbits, for voice, video, and data
 Cellular and PCS Systems – use cellular technologies
 Wireless LANs – cheaper than re-wiring a building
 Bluetooth – short range wireless
 The Wireless Web – wireless is becoming so popular that new
wireless standards for the Web are appearing
6-78
View from Space: Satellite Farming for
Greener Pastures
How are farmers using technology to
better manage their farms?
How has NASA helped farmers manage
their pastures?
How does technology enable farmers to
better control their costs and outputs?
6-79
Around the World: Mobile Buying and
Banking
How much did mobile shopping increase
in 2009? What did mobile phone users
do to make this happen?
What was the increase in mobile
banking in 2009?
What is a point-to-point payment system?
Why is it important?
6-80
VII. Telecommunications Processors
Telecommunications Processors – perform a
variety of support functions in networks
Modems – Modulate/Demodulate – change digital
signals to analog and analog to digital to use common
carrier (voice lines) between computers; most common
processor
Inter-Network Processors – connects networks;
switches, routers, hubs
Multiplexor – allows a single channel to carry multiple
signals at one time
6-81
VIII. Telecommunications Software
Network Management – network operating
systems and telecommunications monitors
6-82
IX. Network Topologies
 Topologies – the structure (or “look”) of a network; 3
basic types: bus, ring, star
 Protocols – formal rules for communications
 Network Architectures
 The Internet’s TCP/IP – Transmission Control
Protocol/Internet Protocol – the standard protocol for
the Internet
 Voice Over IP – Internet telephony, replaces publicswitched service
6-83
IX. Network Topologies
6-84
IX. Network Topologies
The OSI Model – a standard “reference model”
for how messages should be transmitted
Layer 1:
Layer 2:
Layer 3:
Layer 4:
Layer 5:
Layer 6:
Layer 7:
The physical layer
The data link layer
The network layer
The transport layer
The session layer
The presentation layer
The application layer
6-85
6-86
Ottawa Regional Hospital: Lowering Costs
While Converting to VoIP
What was the problem with the old
phone system?
What does the new phone system do for
the hospital complex?
Why is this appropriate for a modern
medical complex?
6-87
X. Bandwidth Alternatives
Bandwidth: the capacity of a network
6-88
6-89
XI. Switching Alternatives
Switching Alternatives – packet
switching and other new ideas to replace
the standard circuit switching of POTS
(Plain Old Telephone Service)
6-90
XII. Network Interoperability
Network Interoperability – common
procedures and protocols so that anyone
on a network can communicate with
anyone else on another network
6-91
6-92