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McGraw-Hill/Irwin ©2005 The McGraw-Hill Companies, All rights reserved
©2005 The McGraw-Hill Companies,
All rights reservedMcGraw-Hill/Irwin
McGraw-Hill/Irwin ©2005 The McGraw-Hill Companies, All rights reserved
CHAPTER 3CHAPTER 3
DATABASES AND DATA WAREHOUSES
DATABASES AND DATA WAREHOUSES
3-3
OPENING CASE STUDYOPENING CASE STUDY
• Chrysler Spins a Competitive Advantage with Supply Chain Management Software
• Chapter 2 – supply chain management is a key business initiative
• Chrysler’s SCM is called SPIN, a Web-based system
3-4
OPENING CASE STUDYOPENING CASE STUDY
• Behind SPIN are powerful databases• Databases store a wealth of information
– Inventory– Work-in-progress– Supplier information– Recall notices– Customer purchases
• This chapter – databases and data warehouses
3-5
STUDENT LEARNING OUTCOMESSTUDENT LEARNING OUTCOMES
1. Describe business intelligence and its role2. Compare databases and data warehouses
by OLTP and OLAP3. List/describe key characteristics of a
relational database4. Define 5 software components of a DBMS
3-6
STUDENT LEARNING OUTCOMESSTUDENT LEARNING OUTCOMES
5. List/describe key characteristics of a data warehouse
6. Define 4 major types of data-mining tools
7. List key considerations in managing information as a resource
3-7
INTRODUCTIONINTRODUCTION
• Organizations need business intelligence
• Business intelligence (BI) – knowledge about your customers, competitors, business partners, competitive environment, and internal operations to make effective, important, and strategic business decisions
3-8
INTRODUCTIONINTRODUCTION
• IT tools help process information to create business intelligence according to:– OLTP
– OLAP
3-9
INTRODUCTIONINTRODUCTION
• Online transaction processing (OLTP) – the gathering of input information, processing that information, and updating existing information to reflect the gathered and processed information– Databases support OLTP
– Operational database – databases that support OLTP
3-10
INTRODUCTIONINTRODUCTION
• Online analytical processing (OLAP) – the manipulation of information to support decision making– Databases can support some OLAP
– Data warehouses only support OLAP, not OLTP
– Data warehouses are special forms of databases that support decision making
3-11
INTRODUCTIONINTRODUCTION
3-12
THE RELATIONAL DATABASE MODEL
THE RELATIONAL DATABASE MODEL
• There are many types of databases
• The relational database model is the most popular
• Relational database – uses a series of logically related two-dimensional tables or files to store information in the form of a database
3-13
Databases Are…Databases Are…
• Collections of information
• Created with logical structures
• With logical ties within the information
• With built-in integrity constraints
3-14
Databases – Collections of InformationDatabases – Collections of Information
• Databases have many tables
• Consider Solomon Enterprises that provides concrete to home and commercial builders. Tables or files include:– Order
– Customer
– Concrete Type
– Employee
– Truck
3-15
Databases – Collections of InformationDatabases – Collections of Information
3-16
Databases – Created with Logical Structures
Databases – Created with Logical Structures
• In databases, the row number is irrelevant
• Not true in spreadsheet software
• In databases, column names are very important. Column names are created in the data dictionary
• Data dictionary – contains the logical structure of the information in a database
3-17
Databases – With Logical Ties Within the Information
Databases – With Logical Ties Within the Information
• Logical ties must exist between the tables or files in a database
• Logical ties are created with primary and foreign keys
• Primary key – field (or group of fields in some cases) that uniquely describes each record
• Can you find primary keys in Figure 3.1 on page 129?
3-18
Databases – With Logical Ties Within the Information
Databases – With Logical Ties Within the Information
• Foreign key – primary key of one file that appears in another file
• Foreign keys help you create logical ties within the information in a database
3-19
Databases – With Logical Ties Within the Information
Databases – With Logical Ties Within the Information
3-20
Databases – With Built-In Integrity Constraints
Databases – With Built-In Integrity Constraints
• Integrity constraints – rules that help ensure the quality of the information
• Examples– Primary keys must be unique
– Foreign keys must be present
– Sales price cannot be negative
– Phone number must have area code
3-21
DATABASE MANAGEMENT SYSTEM TOOLS
DATABASE MANAGEMENT SYSTEM TOOLS
• Database management system (DBMS) – helps you specify the logical organization for a databases and access and use the information within a database– Word processing software = document
– Spreadsheet software = workbook
– DBMS software = database
3-22
DATABASE MANAGEMENT SYSTEM TOOLS
DATABASE MANAGEMENT SYSTEM TOOLS
• 5 software components:1. DBMS engine
2. Data definition subsystem
3. Data manipulation subsystem
4. Application generation subsystem
5. Data administration subsystem
3-23
DATABASE MANAGEMENT SYSTEM TOOLS
DATABASE MANAGEMENT SYSTEM TOOLS
3-24
DBMS EngineDBMS Engine
• DBMS engine – accepts logical requests from the various other DBMS subsystems, converts them into their physical equivalent, and actually accesses the database and data dictionary as they exist on a storage device
• DBMS engine separates the logical from the physical
3-25
DBMS EngineDBMS Engine
• Physical view – how information is physically arranged, stored, and accessed on some type of storage device
• Logical view – how you as a knowledge worker need to arrange and access information
• With a database, you only concern yourself with your logical view
3-26
Data Definition SubsystemData Definition Subsystem
• Data definition subsystem – helps you create and maintain the data dictionary and define the structure of the files in a database
• You must create a data dictionary before entering information into a database
• Module J covers this for Microsoft Access
3-27
Data Manipulation SubsystemData Manipulation Subsystem
• Data manipulation subsystem – helps you add, change, and delete information
• This is your primary DBMS interface as you work with a database– Views
– Report generators
– QBE tools
– SQL
3-28
ViewsViews
• View – allows you to see the contents of a database file– Make whatever changes you want
– Perform simple sorting
– Query to find the location of information
– Looks similar to a workbook with no row numbers
3-29
ViewsViews
3-30
Report GeneratorsReport Generators
• Report generator – helps you quickly define formats of reports and what information you want to see in a report
• You can save report formats and generate reports at any time with up-to-date information
3-31
Report GeneratorsReport Generators
3-32
Report GeneratorsReport Generators
3-33
QBE ToolsQBE Tools
• Query-by-example (QBE) tool – helps you graphically design the answer to a question
• “What driver most often delivers concrete to Triple A Homes?”
3-34
QBE ToolsQBE Tools
3-35
SQLSQL
• Structured query language (SQL) – standardized fourth-generation language found in most DBMSs
• Performs the same task as a QBE tool– But uses a sentence structure instead of point-
and-click interface
• SQL is used mostly by IT people
3-36
Application Generation SubsystemApplication Generation Subsystem
• Application generation subsystem – contains facilities to help you develop transaction-intensive applications– Data entry screen (called forms)
– Programming languages
• Used mostly by IT specialists
3-37
Data Administration SubsystemData Administration Subsystem
• Data administration subsystem – helps you manage the overall database environment– Backup and recovery
– Security management
– Query optimization
– Concurrency control
– Change management
3-38
Data Administration SubsystemData Administration Subsystem
• Backup and recovery– Periodically back up information
– Recover a database if a failure occurs
• Security management– Who has access to what information
– Who can perform certain tasks (e.g., add, change, or delete) on information
3-39
Data Administration SubsystemData Administration Subsystem
• Query optimization– Restructure physical view of information to
optimize response times to queries
• Concurrency control– What happens if two people makes changes to
the same information at the same time?
3-40
Data Administration SubsystemData Administration Subsystem
• Change management– What is the effect of structural changes to a
database?
– What if you add a new column?
– What happens if you delete a column?
– What happens if you change a column’s attributes?
3-41
DATA WAREHOUSES AND DATA MINING
DATA WAREHOUSES AND DATA MINING
• Data warehouses support OLAP and decision making
• Data warehouses do not support OLTP
• Data-mining tools are the tools you use to work with a data warehouse– DBMS software = database
– Data-mining tools = data warehouse
3-42
What Is a Data Warehouse?What Is a Data Warehouse?
• Data warehouse – logical collection of information – gathered from operational databases – used to create business intelligence that supports business analysis activities and decision-making tasks
3-43
What Is a Data Warehouse?What Is a Data Warehouse?
3-44
What Is a Data Warehouse?What Is a Data Warehouse?
• Multidimensional
• Rows and columns
• Also layers
• Many times called hypercubes
• What are the dimensions in Figure 3.8 on page 142?
3-45
What Are Data-Mining Tools?What Are Data-Mining Tools?
• Data-mining tools – software tools that you use to query information in a data warehouse– Query-and-reporting tools
– Intelligence agents
– Multidimensional analysis tools
– Statistical tools
3-46
What Are Data-Mining Tools?What Are Data-Mining Tools?
3-47
Query-And-Reporting ToolsQuery-And-Reporting Tools
• Query-and-reporting tools – similar to QBE tools, SQL, and report generators in the typical database environment
3-48
Intelligent AgentsIntelligent Agents
• Use various artificial intelligence tools such as neural networks and fuzzy logic to form the basis for “information discovery” and building business intelligence
• Help you find hidden patterns in information
• Chapter 4 focuses more on these
3-49
Multidimensional Analysis ToolsMultidimensional Analysis Tools
• Multidimensional analysis (MDA) tools – slice-and-dice techniques that allow you to view multidimensional information from different perspectives– Bring new layers to the front
– Reorganize rows and columns
3-50
Statistical ToolsStatistical Tools
• Help you apply various mathematical models to the information stored in a data warehouse to discover new information– Regression
– Analysis of variance
– And so on
3-51
Data MartsData Marts
• Data warehouses can support all of an organization’s information
• Data marts have subsets of an organizationwide data warehouse
• Data mart – subset of a data warehouse in which only a focused portion of the data warehouse information is kept
3-52
Data MartsData Marts
3-53
Data Mining as a Career OpportunityData Mining as a Career Opportunity
• Knowledge of data mining can be a substantial career opportunity for you– Query and Analysis and Enterprise Analytic Tools
(Business Objects)
– Business Intelligence and Information Access tools (SAS)
– Many in Cognos (the data warehouse leader)
– PowerAnalyzer (Informatica)
3-54
Considerations in Using a Data Warehouse
Considerations in Using a Data Warehouse
• Do you need a data warehouse?– Perhaps database OLAP is sufficient
• Do all employees need the entire data warehouse?– If no, build smaller data marts
• How up-to-date must the information be?
• What data-mining tools do you need?
3-55
MANAGING THE INFORMATION RESOURCE
MANAGING THE INFORMATION RESOURCE
• Information is an organizational resource
• Just like people, capital, and equipment
• It must be managed effectively
3-56
MANAGING THE INFORMATION RESOURCE
MANAGING THE INFORMATION RESOURCE
• Who should oversee your organization’s information resource?– Chief information officer (CIO) – oversees an
organization’s information resource
– Data administration – plans for, oversees the development of, and monitors the information resource
– Database administration – technical and operational aspects of managing information
3-57
MANAGING THE INFORMATION RESOURCE
MANAGING THE INFORMATION RESOURCE
• Is information ownership a consideration?– If you create information, you “own” it
– You will also share it with others
– Because you “own” it, you are responsible for its quality
3-58
MANAGING THE INFORMATION RESOURCE
MANAGING THE INFORMATION RESOURCE
• How “clean” must your information be?– Duplicate information (records) must be
eliminated
– Inaccurate information must be corrected
– Information forms the basis of business intelligence
– If your business intelligence is bad, you will make poor decisions
3-59
CAN YOU…CAN YOU…
1. Describe business intelligence and its role2. Compare databases and data warehouses
by OLTP and OLAP3. List/describe key characteristics of a
relational database4. Define 5 software components of a DBMS
3-60
CAN YOU…CAN YOU…
5. List/describe key characteristics of a data warehouse
6. Define 4 major types of data-mining tools
7. List key considerations in managing information as a resource
McGraw-Hill/Irwin ©2005 The McGraw-Hill Companies, All rights reserved
CHAPTER 3CHAPTER 3
End of Chapter 3End of Chapter 3
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