1. technology and computing
2. software
3. databases

Business Intelligence:
A Managerial Perspective on
Analytics (3rd Edition)
Chapter 2:
Data Warehousing
Learning Objectives
 Understand the basic definitions and
concepts of data warehouses
 Learn different types of data warehousing
architectures; their comparative
advantages and disadvantages
 Describe the processes used in developing
and managing data warehouses
 Explain data warehousing operations
(Continued…)
Copyright © 2014 Pearson Education, Inc.
Slide 2- 2
Learning Objectives
 Explain the role of data warehouses in
decision support
 Explain data integration and the extraction,
transformation, and load (ETL) processes
 Describe real-time (a.k.a. right-time and/or
active) data warehousing
 Understand data warehouse administration
and security issues
Copyright © 2014 Pearson Education, Inc.
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Opening Vignette…
Isle of Capri Casinos Is Winning with
Enterprise Data Warehouse
 Company background
 Problem description
 Proposed solution
 Results
 Answer & discuss the case questions.
Copyright © 2014 Pearson Education, Inc.
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Questions for the Opening Vignette
1. Why is it important for Isle to have an EDW?
2. What were the business challenges or opportunities that
Isle was facing?
3. What was the process Isle followed to realize EDW?
Comment on the potential challenges Isle might have
had going through the process of EDW development.
4. What were the benefits of implementing an EDW at
Isle? Can you think of other potential benefits that were
not listed in the case?
5. Why do you think large enterprises like Isle in the
gaming industry can succeed without having a capable
data warehouse/business intelligence infrastructure?
Copyright © 2014 Pearson Education, Inc.
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Main Data Warehousing Topics
 DW definition
 Characteristics of DW
 Data Marts
 ODS, EDW, Metadata
 DW Framework
 DW Architecture & ETL Process
 DW Development
 DW Issues
Copyright © 2014 Pearson Education, Inc.
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What is a Data Warehouse?

A physical repository where relational data
are specially organized to provide
enterprise-wide, cleansed data in a
standardized format

“The data warehouse is a collection of
integrated, subject-oriented databases
designed to support DSS functions, where
each unit of data is non-volatile and
relevant to some moment in time”
Copyright © 2014 Pearson Education, Inc.
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A Historical Perspective to
Data Warehousing
ü
ü
ü
ü
ü
Mainframe computers
Simple data entry
Routine reporting
Primitive database structures
Teradata incorporated
1970s
ü
ü
ü
ü
ü
Centralized data storage
Data warehousing was born
Inmon, Building the Data Warehouse
Kimball, The Data Warehouse Toolkit
EDW architecture design
1980s
ü
ü
ü
ü
ü
1990s
Mini/personal computers (PCs)
Business applications for PCs
Distributer DBMS
Relational DBMS
Teradata ships commercial DBs
ü Business Data Warehouse coined
ü
ü
ü
ü
ü
2000s
ü
ü
ü
ü
ü
ü
ü
Big Data analytics
Social media analytics
Text and Web Analytics
Hadoop, MapReduce, NoSQL
In-memory, in-database
2010s
Exponentially growing data Web data
Consolidation of DW/BI industry
Data warehouse appliances emerged
Business intelligence popularized
Data mining and predictive modeling
Open source software
SaaS, PaaS, Cloud Computing
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Characteristics of DWs
 Subject oriented
 Integrated
 Time-variant (time series)
 Nonvolatile
 Summarized
 Not normalized
 Metadata
 Web based, relational/multi-dimensional
 Client/server, real-time/right-time/active …
Copyright © 2014 Pearson Education, Inc.
Slide 2- 9
Data Mart
A departmental small-scale “DW” that
stores only limited/relevant data
 Dependent data mart
A subset that is created directly from a
data warehouse
 Independent data mart
A small data warehouse designed for a
strategic business unit or a department
Copyright © 2014 Pearson Education, Inc.
Slide 2- 10
Other DW Components
 Operational data stores (ODS)
A type of database often used as an interim area
for a data warehouse
 Oper marts - an operational data mart.
 Enterprise data warehouse (EDW)
A data warehouse for the enterprise.
 Metadata
Data about data. In a data warehouse, metadata
describe the contents of a data warehouse and
the manner of its acquisition and use
Copyright © 2014 Pearson Education, Inc.
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Application Case 2.1
A Better Data Plan: Well-Established TELCOs
Leverage Data Warehousing and Analytics to
Stay on Top in a Competitive Industry
Questions for Discussion
1. What are the main challenges for TELCOs?
2. How can data warehousing and data analytics
help TELCOs in overcoming their challenges?
3. Why do you think TELCOs are well suited to
take full advantage of data analytics?
Copyright © 2014 Pearson Education, Inc.
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A Generic DW Framework
No data marts option
Applications
(Visualization)
Data
Sources
Access
ETL
Process
Metadata
Extract
POS
Transform
Enterprise
Data warehouse
Integrate
Other
OLTP/wEB
Data mart
(Finance)
Load
Replication
External
data
Data mart
(Engineering)
Data mart
(...)
Copyright © 2014 Pearson Education, Inc.
/ Middleware
Data mart
(Marketing)
Select
Legacy
Routine
Business
Reporting
API
ERP
Data/text
mining
OLAP,
Dashboard,
Web
Custom built
applications
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Application Case 2.2
Data Warehousing Helps MultiCare
Save More Lives
Questions for Discussion
1. What do you think is the role of data
warehousing in healthcare systems?
2. How did MultiCare use data warehousing
to improve health outcomes?
Copyright © 2014 Pearson Education, Inc.
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DW Architecture
Three-tier architecture

1.
2.
3.

Data acquisition software (back-end)
The data warehouse that contains the data &
software
Client (front-end) software that allows users to
access and analyze data from the warehouse
Two-tier architecture
First two tiers in three-tier architecture is combined into
one
… sometimes there is only one tier?
Copyright © 2014 Pearson Education, Inc.
Slide 2- 15
DW Architectures
Tier 1:
Client workstation
Tier 1:
Client workstation
Tier 2:
Application server
Tier 3:
Database server
Tier 2:
Application & database server
Copyright © 2014 Pearson Education, Inc.
Slide 2- 16
Data Warehousing Architectures
 Issues to consider when deciding
which architecture to use:
 Which database management system (DBMS)
should be used?
 Will parallel processing and/or partitioning be
used?
 Will data migration tools be used to load the data
warehouse?
 What tools will be used to support data retrieval
and analysis?
Copyright © 2014 Pearson Education, Inc.
Slide 2- 17
A Web-Based DW Architecture
Web pages
Client
(Web browser)
Internet/
Intranet/
Extranet
Application
Server
Web
Server
Data
warehouse
Copyright © 2014 Pearson Education, Inc.
Slide 2- 18
Alternative DW Architectures
(a) Independent Data Marts Architecture
ETL
Source
Systems
Staging
Area
Independent data marts
(atomic/summarized data)
End user
access and
applications
(b) Data Mart Bus Architecture with Linked Dimensional Datamarts
ETL
Source
Systems
Staging
Area
Dimensionalized data marts
linked by conformed dimensions
(atomic/summarized data)
End user
access and
applications
(c) Hub and Spoke Architecture (Corporate Information Factory)
ETL
Source
Systems
Staging
Area
Normalized relational
warehouse (atomic data)
End user
access and
applications
Dependent data marts
(summarized/some atomic data)
Alternative DW Architectures
(d) Centralized Data Warehouse Architecture
ETL
Source
Systems
Staging
Area
Normalized relational
warehouse (atomic/some
summarized data)
End user
access and
applications
(e) Federated Architecture
Data mapping / metadata
Existing data warehouses
Data marts and legacy systems
Logical/physical integration of
common data elements
End user
access and
applications
 Each architecture has advantages
and disadvantages!
 Which architecture is the best?
Ten factors that potentially affect the
architecture selection decision
1. Information
interdependence between
organizational units
2. Upper management’s
information needs
3. Urgency of need for a data
warehouse
4. Nature of end-user tasks
5. Constraints on resources
6. Strategic view of the data
warehouse prior to
implementation
7. Compatibility with existing
systems
8. Perceived ability of the inhouse IT staff
9. Technical issues
10. Social/political factors
Copyright © 2014 Pearson Education, Inc.
Slide 2- 21
Teradata Corp. DW Architecture
Copyright © 2014 Pearson Education, Inc.
Slide 2- 22
Data Integration and the Extraction,
Transformation, and Load (ETL) Process
 ETL = Extract Transform Load
 Data integration
Integration that comprises three major processes: data
access, data federation, and change capture.
 Enterprise application integration (EAI)
A technology that provides a vehicle for pushing data
from source systems into a data warehouse
 Enterprise information integration (EII)
An evolving tool space that promises real-time data
integration from a variety of sources, such as relational or
multidimensional databases, Web services, etc.
Copyright © 2014 Pearson Education, Inc.
Slide 2- 23
Data Integration and the Extraction,
Transformation, and Load (ETL) Process
Transient
data source
Packaged
application
Data
warehouse
Legacy
system
Extract
Transform
Cleanse
Load
Data mart
Other internal
applications
Copyright © 2014 Pearson Education, Inc.
Slide 2- 24
ETL (Extract, Transform, Load)
 Issues affecting the purchase of an ETL tool
 Data transformation tools are expensive
 Data transformation tools may have a long learning
curve
 Important criteria in selecting an ETL tool
 Ability to read from and write to an unlimited number of
data sources/architectures
 Automatic capturing and delivery of metadata
 A history of conforming to open standards
 An easy-to-use interface for the developer and the
functional user
Copyright © 2014 Pearson Education, Inc.
Slide 2- 25
Data Warehouse Development
Data warehouse development approaches



Inmon Model: EDW approach (top-down)
Kimball Model: Data mart approach
(bottom-up)
Which model is best?
 Table 2.3 provides a comparative analysis
between EDW and Data Mart approach
 One alternative is the hosted warehouse
Copyright © 2014 Pearson Education, Inc.
Slide 2- 26
Application Case 2.5
Starwood Hotels & Resorts Manages
Hotel Profitability with Data Warehousing
Questions for Discussion
1. How big and complex are the business
operations of Starwood Hotels & Resorts?
2. How did Starwood Hotels & Resorts use
data warehousing for better profitability?
3. What were the challenges, the proposed
solution, and the obtained results?
Copyright © 2014 Pearson Education, Inc.
Slide 2- 27
Additional Data Warehouse Considerations
Hosted Data Warehouses
 Benefits:
 Requires minimal investment in infrastructure
 Frees up capacity on in-house systems
 Frees up cash flow
 Makes powerful solutions affordable
 Enables solutions that provide for growth
 Offers better quality equipment and software
 Provides faster connections
 … more in the book
Copyright © 2014 Pearson Education, Inc.
Slide 2- 28
Representation of Data in DW
 Dimensional Modeling
 A retrieval-based system that supports high-volume
query access
 Star schema
 The most commonly used and the simplest style of
dimensional modeling
 Contain a fact table surrounded by and connected to
several dimension tables
 Snowflakes schema
 An extension of star schema where the diagram
resembles a snowflake in shape
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Slide 2- 29
Multidimensionality
The ability to organize, present, and analyze data by
several dimensions, such as sales by region, by
product, by salesperson, and by time (four
dimensions)
 Multidimensional presentation
 Dimensions: products, salespeople, market segments,
business units, geographical locations, distribution
channels, country, or industry
 Measures: money, sales volume, head count, inventory
profit, actual versus forecast
 Time: daily, weekly, monthly, quarterly, or yearly
Copyright © 2014 Pearson Education, Inc.
Slide 2- 30
Star versus Snowflake Schema
Star Schema
Dimension
TIME
Snowflake Schema
Dimension
PRODUCT
Dimension
MONTH
Quarter
Brand
M_Name
...
...
...
Fact Table
SALES
Dimension
QUARTER
UnitsSold
Dimension
BRAND
Brand
Dimension
DATE
Date
LineItem
...
...
Q_Name
...
Dimension
GEOGRAPHY
Division
Country
...
...
...
Dimension
CATEGORY
Category
Fact Table
SALES
...
Dimension
PEOPLE
Dimension
PRODUCT
...
UnitsSold
...
Dimension
PEOPLE
Dimension
STORE
Division
LocID
...
...
Dimension
LOCATION
State
...
Copyright © 2014 Pearson Education, Inc.
Slide 2- 31
Analysis of Data in DW
 OLTP vs. OLAP…
 OLTP (online transaction processing)
 Capturing and storing data from ERP, CRM, POS, …
 The main focus is on efficiency of routine tasks
 OLAP (Online analytical processing)
 Converting data into information for decision support
 Data cubes, drill-down / rollup, slice & dice, …
 Requesting ad hoc reports
 Conducting statistical and other analyses
 Developing multimedia-based applications
 …more in the book
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Slide 2- 32
OLAP vs. OLTP
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Slide 2- 33
OLAP Operations
 Slice - a subset of a multidimensional array
 Dice - a slice on more than two dimensions
 Drill Down/Up - navigating among levels of data
ranging from the most summarized (up) to the
most detailed (down)
 Roll Up - computing all of the data relationships
for one or more dimensions
 Pivot - used to change the dimensional
orientation of a report or an ad hoc query-page
display
Copyright © 2014 Pearson Education, Inc.
Slide 2- 34
A 3-dimensional
OLAP cube with
slicing
operations
e
Ti
m
Slicing
Operations on a
Simple TreeDimensional
Data Cube
Product
Cells are filled
with numbers
representing
sales volumes
Geography
OLAP
Sales volumes of
a specific Product
on variable Time
and Region
Sales volumes of
a specific Region
on variable Time
and Products
Sales volumes of
a specific Time on
variable Region
and Products
Copyright © 2014 Pearson Education, Inc.
Slide 2- 35
Variations of OLAP



Multidimensional OLAP (MOLAP)
OLAP implemented via a specialized
multidimensional database (or data store) that
summarizes transactions into multidimensional
views ahead of time
Relational OLAP (ROLAP)
The implementation of an OLAP database on
top of an existing relational database
Database OLAP and Web OLAP (DOLAP and
WOLAP); Desktop OLAP,…
Copyright © 2014 Pearson Education, Inc.
Slide 2- 36
Technology Insights 2.2
Hands-On DW with MicroStrategy
 A wealth of teaching and learning
resources can be found at TUN portal
www.teradatauniversitynetwork.com
 The available resources include
scripted demonstrations,
assignments, white papers, etc…
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Slide 2- 37
DW Implementation Issues
 Identification of data sources and governance
 Data quality planning, data model design
 ETL tool selection
 Establishment of service-level agreements
 Data transport, data conversion
 Reconciliation process
 End-user support
 Political issues
 … more in the book
Copyright © 2014 Pearson Education, Inc.
Slide 2- 38
Successful DW Implementation
Things to Avoid
 Starting with the wrong sponsorship chain
 Setting expectations that you cannot meet
 Engaging in politically naive behavior
 Loading the data warehouse with information just
because it is available
 Believing that data warehousing database design
is the same as transactional database design
 Choosing a data warehouse manager who is
technology oriented rather than user oriented
 … more in the book
Copyright © 2014 Pearson Education, Inc.
Slide 2- 39
Failure Factors in DW Projects

Lack of executive sponsorship
 Unclear business objectives
 Cultural issues being ignored

Change management

Unrealistic expectations
 Inappropriate architecture
 Low data quality / missing information
 Loading data just because it is available
Copyright © 2014 Pearson Education, Inc.
Slide 2- 40
Massive DW and Scalability

Scalability

The main issues pertaining to scalability:


The amount of data in the warehouse
How quickly the warehouse is expected to
grow
 The number of concurrent users
 The complexity of user queries

Good scalability means that queries and
other data-access functions will grow
linearly with the size of the warehouse
Copyright © 2014 Pearson Education, Inc.
Slide 2- 41
Real-Time/Active DW/BI
 Enabling real-time data updates for
real-time analysis and real-time
decision making is growing rapidly
 Push vs. Pull (of data)
 Concerns about real-time BI
 Not all data should be updated continuously
 Mismatch of reports generated minutes apart
 May be cost prohibitive
 May also be infeasible
Copyright © 2014 Pearson Education, Inc.
Slide 2- 42
Enterprise Decision Evolution
and Data Warehousing
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Slide 2- 43
Real-Time/Active DW at Teradata
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Slide 2- 44
Traditional versus Active DW
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Slide 2- 45
DW Administration and Security
 Data warehouse administrator (DWA)
 DWA should…
 have the knowledge of high-performance software, hardware
and networking technologies
 possess solid business knowledge and insight
 be familiar with the decision-making processes so as to suitably
design/maintain the data warehouse structure
 possess excellent communications skills
 Security and privacy is a pressing issue in DW
 Safeguarding the most valuable assets
 Government regulations (HIPAA, etc.)
 Must be explicitly planned and executed
Copyright © 2014 Pearson Education, Inc.
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The Future of DW
 Sourcing…
 Web, social media, and Big Data
 Open source software
 SaaS (software as a service)
 Cloud computing
 Infrastructure…
 Columnar
 Real-time DW
 Data warehouse appliances
 Data management practices/technologies
 In-database & In-memory processing New DBMS
 Advanced analytics
 …
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Slide 2- 47
Free of Charge DW Portal
for Teaching & Learning
 www.TeradataUniversityNetwork.com
 Password to signup: <check with your instructor>
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Slide 2- 48
End of the Chapter
 Questions, comments
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Slide 2- 49
All rights reserved. No part of this publication may be reproduced,
stored in a retrieval system, or transmitted, in any form or by any
means, electronic, mechanical, photocopying, recording, or otherwise,
without the prior written permission of the publisher. Printed in the
United States of America.
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