1) While testing an incremental ETL load, you notice that duplicate records are being inserted into the target table. What is the most likely cause?
2) You are performing a data reconciliation test, and the source table has a different structure than the target table. What should you focus on first?
3) During an ETL load, a complex transformation rule was applied to convert currency values based on historical exchange rates. What type of test would be most appropriate to ensure accuracy?
4) In an ETL job, data from multiple sources needs to be aggregated and deduplicated. Which approach would ensure that only unique records are loaded into the target?
5) You are performing data validation on an ETL pipeline that uses multiple transformations. Which of the following is NOT a best practice?
6) During ETL testing, you encounter a NULL value in a target field that should never be null according to business rules. What is the most likely reason?
7) Which of the following methods is most effective for verifying that an ETL process successfully updates only modified records in the target?
8) You are testing a transformation where a CASE statement is used to convert status codes. Which type of testing would most effectively ensure accuracy of this transformation?
9) If you are required to test the ETL pipeline's resilience to corrupted source data, which of the following techniques would be most appropriate?
10) A company requires real-time data updates from a source system with frequent changes. Which ETL method is most suitable?
11) In ETL, “Data Lineage” refers to:
12) Which testing approach helps ensure that sensitive data fields are correctly masked in a data pipeline?
13) Which of the following would best validate a target table's data consistency across multiple ETL loads?
14) During an ETL job, a column transformation for a complex business rule is failing intermittently. Which strategy would best help you debug the issue?
15) When testing a multi-source ETL load, you find discrepancies in the joined data. What should you check first?
16) In ETL Testing, which is an essential step when testing transformations with aggregate calculations?
17) You find that a large ETL load is repeatedly failing halfway through. What is the best first step?
18) When performing "End-to-End Testing" in ETL, which scenario should you prioritize?
19) You notice that a specific ETL process fails when handling null or blank values in critical fields. What type of test case could help prevent this?
20) Which tool or feature in ETL testing can help you verify that the ETL process captures all audit information?
