1. Telecommunication Case Study CS 543 – Data Warehousing

2. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS2 Steps Select the business process Declare the grain Choose the dimensions Identify the facts Choosing the duration of the database

3. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS3 Data Warehouse Bus Architecture Bottom up approach with conformed dimensions and standardized facts based on dimensional modeling By defining a standard bus interface for the data warehouse environment, separate data marts can be implemented by different groups at different times. The separate data marts can be plugged together and usefully coexist if they adhere to the standard. Data warehouse bus matrix – an enterprise wide representation of business processes and business dimensions, indicating common dimensions

4. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS4 Data Warehouse Bus Matrix

5. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS5 Customer Billing Process Service line number (individual number) Customer (a customer can have several service lines) Sales representative, organization, and channel (deals with individual customers) Rate plan (constant for a given bill, but can change over time) Bill generated for each customer containing all service line numbers owned by the customer

6. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS6 Draft Schema for Customer Billing

7. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS7 General Design Review Considerations Granularity  Fact granularity  Dimension granularity Data dimension Degenerate dimensions Dimension decodes and descriptions Surrogate keys Too many (or too few) dimensions

8. CS 543 - Data Warehousing (Sp 2007-2008) - Asim Karim @ LUMS8 Revised Schema