1. Data Warehousing/Loading the DW—Topics
Review of Steps & Components
SQL Server Integration Services
Define Data Sources
Create Packages & Process Flows
Data Flows for Dimension Tables
Data Flows for Fact Tables
Lookup Translations
Importing Excel Data

2. Steps and Components Source Systems—provide raw data to the DW
Integration Services—Provide transformation and loading services from source data to DW
Data Warehouse—Customized data store for Business Intelligence
Analysis Services—Tools for data mining and reporting
Reporting Services—Out old friend acting on an enhanced data store

3. Star Schema & Dimension Tables
Dimension Tables represent concepts (entities) used to group data in the fact tables
Also contain descriptive attributes of the entity represented by the dimension table
Simplest way for nontechnical users to picture the data
Relate to FKs in the fact tables

4. Design Steps
It is impractical to design a one-source DW as the first deliverable
Identify initial scope of DW
Problem Statement
Business Requirements
Build DW Data Model
Business Processes to address requirements
Level of Detail
Fact Tables (what we are measuring)
Dimension Tables (how we look at the data)

5. SQL Server Integration Services
SSIS creates projects containing packages to select, transform, and load data
From a data source
To a data destination (DW)
Start projects through Business Intelligence Studio (Same as Reporting Services designers)
Packages can be narrowly or broadly focused
Recommend narrowly focused packages to do one specific task

6. Create New Integration Services Project

7. Create Data Sources Right-Click Data Sources in Solution Explorer
Create data sources for source and destination DB

8. Define Process Flow
Process flow defines steps needed to perform package tasks
Process flow tasks are found in the toolbar
Add a data flow task to the process flow
Set name property in properties
Define Data flow task by double-clicking
Process flows can be simple or incredibly complex

9. Define Data Flow
Middle of Design Area
Add source and destination data sources to Connection Managers area—Right-click
Select New connection from data source…
Select all sources needed for current transformation
Source DB
Destination (DW) DB

10. Define Data Flow (cont.)
Data flows start with sources that provide columns of data
End with an output destination
Along the way…
Columns can be added
Other sources
Calculations
Columns can be transformed
Columns can be ignored
Flow columns map to columns in destination table

11. Adding Data Source & Destination
Add Data Source & Destination controls from toolbox
OLEDB Data Source & Destination for SQL Server
Several other source and destination types available
Set Name properties

12. Configure Data Source Control
Double-click
Choose avail. Connection Manager
Select Data access mode
Build queries if needed
Use view or SP
Use table

13. Configure Data Destination Control
Drag green arrow from source control to destination control
Set connection manager to DW Set name of table or view to DW destination table
Select Mappings

14. Configure Data Destination Control (cont.)
Confirm column mappings from source to dest.
Drag source col onto dest. col if necessary

15. Modify Process Flow New data is appended to destination table
If we want to empty the destination table we can add an Execute SQL Task control
Set SQL statement to a DELETE statement

16. Loading Fact Tables Lookup Translations
Fact table loading similar to dimension table loading
More likely to be based on a query instead of a table
Needs Lookup translations to map from available FKs in source DB to Dimension keys in destination table
Lookup Translations

17. Lookup Translations Add Lookup control to data flow from toolbox
Sequence is (usually) not important
Set table on which to perform lookup action
Use Columns tab to set lookup

18. Lookup Translations (cont.)
Confirm column mappings for lookup values
Select value to be returned
Select Replace PK if available
Otherwise select <add as new column>

19. Importing Excel Data
See government statistical data in excel format
Create new package as before
Add Excel Source
Set name property

20. Importing Excel Data (cont.)
Double-click Excel source to configure
New connection

21. Importing Excel Data (cont.)
Find Excel file
Set version
Decide whether layout supports providing column names

22. Importing Excel Data (cont.)
Excel data is likely to need some transformations
Unusual data typing in Excel
Unpivoting pivot tables
Extracting data
I recommend getting rid of messy data in Excel source file if possible before importing
Derived Column Control
Data Type Conversion

23. Importing Excel Data (cont.)
As with other data flows the results are a set of columns
Final step is to map the developed set of columns to the destination data source columns

24. Importing Data--Summary
There are hundreds (or thousands) of combinations of data sources and transformations to result in data for DW
Topics not covered
Validating data
Many different transformations
Using alternative data sources
Easy loads are easy
Difficult transformations are more challenging