12.8. REVIEW QUESTIONS

  1. Give three reasons why you think ETL functions are most challenging in a data warehouse environment.

  2. Name any five types of activities that are part of the ETL process. Which of these are time-consuming?

  3. The tremendous diversity of the source systems is the primary reason for their complexity. Do you agree? If so, explain briefly why.

  4. What are the two general categories of data stored in source operational systems? Give two examples for each.

  5. Name five types of the major transformation tasks. Give an example for each.

  6. Describe briefly the entity identification problem in data integration and consolidation. How do you resolve this problem?

  7. What is key restructuring? Explain why it is needed.

  8. Define initial load, incremental load, and full refresh.

  9. Explain the difference between destructive merge and constructive merge for applying data to the data warehouse repository. When do you use these modes?

  10. When is a full data refresh preferable to an incremental load? Can you think of an example?

Get DATA WAREHOUSING FUNDAMENTALS: A Comprehensive Guide for IT Professionals now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.