30 TOP ETL Testing Interview Questions and Answers for freshers and experienced pdf

1. What is ETL?   
2. What is the difference between etl tool and olap tools?
3. What is ODS (operation data source)?
4. Where do we use connected and unconnected lookups?
5. Where do we use semi and non additive facts?
6. What are the different Lookup methods used in Informatica?
7. What is a mapping, session, worklet, workflow, mapplet?
8. Do we need an ETL tool? When do we go for the tools in the market?
9. What is Full load & Incremental or Refresh load?
10. How can we use mapping variables in Informatica? Where do we use them?
11. What are critical success factors?
12. What is data cube technology used for?
13. What is data cleaning?
14. Explain how to mine an OLAP cube?
15. What are different stages of data mining?
16. What are the different problems that data mining can solve?
17. What is Data Purging?
18. What is BUS schema?
19. What is conformed fact? What are conformed dimensions used for?
20. What is real time data-wearhousing?
21. Explain the use lookup tables and Aggregate tables?
22. Define slowly changing dimensions (SCD)?
23. What is cube grouping?
24. What is data wearhousing?
25. What is virtual Data Wearhousing?
26. What is active data wearhousing?
27. What is data modeling and data mining?
28. What is ETL process ?How many steps ETL contains explain with example?   
29. Define non-additive facts?   
30. Compare ETL & Manual development?