ARCHITECTING A DATA WAREHOUSE:
A CASE STUDY
Project: zBis
Carl Zeiss Vision North America
SPEAKER: ELIZABETH DIAMOND
SAN FRANCISCO SQL SERVER USER GROUP
SEPTEMBER 9, 2009
MARK GINNEBAUGH, USER GROUP LEADER
www.bayareasql.org

The Journey
Determined Need for Enterprise Data Warehouse
Worked with Business Users to Understand Business
Requirements
Determined Software Requirements
MS SQL Server 2005 & 2008
MS SSIS (ETL Tool)
MS SSAS (Analytic Cube Tool)
MS SSRS & Excel (Reporting Tools)
SharePoint for Deploying Reports over Company
Intranet
Designed and Developed zBis Data Warehouse

Z BIS = What We Will Deliver
This project team will deliver the following:
X Consolidated reporting for Carl Zeiss Vision
North America
X Reporting that is consistent and from one
data warehouse
X Reporting that is easy to use and easy to
access
X Toolset will be flexible and able to grow and
change with our business
X Phase I rock solid download from ERP/Manf
– Providing ability to review lab information
as a lab network – not individual silos – with
accurate reporting across all products and
services
We will deliver the best product possible based on the information we
can place in our data warehouse!

• Reporting from cubes – off source systems only –
No data warehouse
• Disparate data systems with different results from
each
• Most systems not balanced to GL
• Reporting for each business unit only
• No reporting across all business units

Transactional Cube of Approach
Sales Queries Other Reports Sales Reports
Corporate
Download
Data Mart Data Mart Data Mart
Finance Inventory Sales & Marketing
ETL Loads
ETL Load
ODS/Staging
Operational Data Store
ETL Load
ERP Manufacturing Other

BI Tools/Analytics Active
Excel Static Reports
Reports
PerformancePoint Server
SharePoint
SQL
SQL Analytics
Reporting
Server (SSAS)
Server
Aggregated Finance Inventory
Sales
Data Mart Data Mart Data Mart
Data Mart
TBD
ETL Load (SSIS)
Data Warehouse
ETL Load (SSIS)
ODS/Staging
Operational Data Store
ETL Load (SSIS)
ERP Manufacturing SW Other Data Sources

Introduction to Data Warehousing
What is a Data Warehouse System
Why a Data Warehouse Vs. Cubes on Source Systems
Star Schema Vs. Transactional Data Warehouses
Star Schemas ease of system integrating
Star Schemas provide substantial performance gains
Star Schemas hierarchy capabilities or Drill Down
Capabilities
Ralph Kimball Developed Current Industry Standards for Star
Schema – Dimensions and Facts

Data Warehouse Project Lifecycle
Technical Product
Architecture Selection &
Design Installation
Project
Business Data Staging Testing
Planning Dimensional Physical
Requirement Design & ETL & Deployment Maintenance
Modeling Design
Definition Development DW/DM
Report Report Report
Specifications Development Testing
Project Management

4 + 1 – Steps
Dimensional Design Process
Ralph Kimball’s Process for Developing Star Schemas
1. Determine Business Process
Model business Processes
Each Process will determine 1 or more Facts
Design DW by Business Process Not Business Unit
2. Identify the Grain of the Fact
• What does 1 row in Fact table represent
• Transactional or Summary
3. Design the DW Dimensions
4. Design the DW Facts
+1 Determine Hierarchies

Business Driven vs. Data Driven
Design DW/BI System via Business Process
Develop DW/BI System via Data from Source Systems
Profile Data as early as possible
Understand data and design DW using existing data
Design & Develop using both Business Process and available
Data if possible

Understanding Your Business
Identify key business sponsors for DW project
Use Corporate Org Chart
Setup initial interviews with key sponsors
Develop Business Process diagrams
Develop high level Use Case Diagrams
Determine Business Hierarchies

The Business Executive Interview
• What are the objectives of your organization?
• What Business goals do you want to accomplish with the
development of zBis data warehouse System?
• How do you measure success? How do you know you are doing
well? How often do you measure your corporate performance?
• What are your key business issues that you are trying to solve
from the zBis system? If these issues are not justified what is the
impact to your department and organization?

The Business Executive Interview
• How do you identify problems or know when you might be
headed for trouble?
• How do you spot exceptions in your business? What
opportunities exist to dramatically impact your business based
on improved access to information? What is the financial
impact
• If you could….., What would it mean to your business?
• What is your vision to better leverage information within your
organization?
• How do you anticipate that your staff will interact directly with
this information?

The Business Manager Interview
• What are the objectives of your department?
• What are you trying to accomplish? How would do you go
about achieving your objectives?
• What are your success metrics?
• How do you know you are doing well?
• How often do you measure your department/team?
• How do you anticipate that your staff will interact directly with
this information?

Business Process Diagrams
Understand Business Requirements for building
DW/BI system.
Defines the Measures and Dimensions for data
warehouse

Determine Hierarchies
Customer Hierarchies – Sales Channels
Distribution Channels
Business Channels
Customer Channels
Product Divisions
Sales Organizations
Sales Office
Buy Groups/Directly Purchase

Determine Hierarchies
Product Hierarchy
Manufacturer
Brand
Product Type – Each product type had own Hierarchy
Lens
Service
Equipment
etc…
Design
Make/Model

Determine Hierarchies
Geo Hierarchy
Sales Division
Sales Region
Sales Territory

Conformed Dimensions
Standardized dimensions across data warehouse
Dimensions are associated with multiple business
processes
Determine by using Bus Matrix & enforced in ETL
Conformed Dimensions are shared and consistent
across fact tables

Use Data Warehouse BUS Matrix
Use Data Warehouse BUS Matrix for
Understanding & mapping of Business Processes and
Dimensions
Ongoing DW/BI planning efforts
Team & Management Communications
Understand Business Process unions across the enterprise

Data Warehouse BUS Matrix
Date Company Customer Product Geo Dist Ctr Promo
Company X X X X X X
Sales
Customer X X X X X X
Discounts
Product X X X X X X X
Cost
Company X X X
Inventory
Dist Ctr X X X
Inventory

Develop Dimensional Schema

Slow Changing Dimensions
Type 1 – Overwrite existing Dimension Row
Use when don’t need to keep history data row
Can be used to correct bad data
Type 2 – Create a new Dimension Row
Use date and/or active non-active fields to identify current
and inactive data rows
Type 3 – Keep old and add new attributes in Dimension Row
Allow Alternate realities to exist simultaneously in one
Dimension Row
Slow Changing Dimensions are handled in the ETL

Type of Dimensions
Mini-Dimension
Junk Dimensions
Outrigger Dimensions
Small Static Dimensions
Lookup tables

Type of Facts
Transaction Fact Tables
Snapshot Fact Tables
Accumulating Snapshot Fact Tables
Consolidated or Aggregated Fact Tables

Bridge Tables

Bridge Tables

Recommended Reading list
The Data Warehouse Toolkit: The Complete Guide to Dimensional
Modeling (Second Edition) by Ralph Kimball and Margy Ross
The MicrosoftData Warehouse Toolkit: With SQL Server2005 and the
MicrosoftBusiness Intelligence Toolset by Joy Mundy, Warren
Thornthwaite, and Ralph Kimball
Building a Data Warehouse: With Examples in SQL Server (Expert's Voice)
by Vincent Rainardi
The Data Warehouse Lifecycle Toolkit by Ralph Kimball, Margy Ross,
Warren Thornthwaite, and Joy Mundy
The Data Warehouse ETL Toolkit: Practical Techniques for Extracting,
Cleanin by Ralph Kimball and Joe Caserta

Elizabeth Diamond
LSI Data Management / Partner with DesignMind
Sr. Data Warehouse Architect
lizd@techrecover.com
Phone: 415-990-8204

www.bayareasql.org
To attend our meetings or inquire about speaking opportunities,
please contact:
Mark Ginnebaugh, User Group Leader mark@designmind.com