1) In a project involving sales data, ETL transformations calculate quarterly totals. What’s an important testing approach?

2) A financial institution needs ETL validation to ensure no data loss between data extraction and loading. Which test is most effective?

3) In an ETL job that runs nightly, the system often encounters high data volumes that slow down processing. What test should be prioritized?

4) Your ETL job is set up to handle JSON and XML files from API sources. How should you test file format compatibility?

5) In an ETL process that prepares marketing data, time-sensitive campaigns must be processed within an hour of being received. What type of testing is essential?

6) Your ETL job is designed to process data from an HR system, where employee records are updated daily. If an employee is terminated, the data should be flagged accordingly in the target database. How would you verify that terminated records are processed correctly?

7) During ETL processing, your job reads data from multiple financial data sources and performs currency conversions for analysis. However, exchange rates can fluctuate frequently. How would you ensure currency accuracy across different data loads?

8) In a retail data warehouse, sales records are loaded daily. The ETL team discovers that some transactions appear twice due to system lags in data feeds. What’s the best way to validate and fix this issue?

9) An ETL process loads customer demographic data into a marketing database, where addresses are standardized into a specific format. Recently, the format requirements changed, impacting how addresses should appear. How would you validate this change?

10) In a healthcare ETL pipeline, patient data is anonymized to comply with data protection regulations. How would you confirm that sensitive data is appropriately masked before loading?

11) An ETL process processes product inventory from multiple warehouses and consolidates it into a central warehouse management system. How would you ensure inventory counts are correct in the final system?

12) Your ETL pipeline aggregates monthly sales data from various regions. One region’s data is delayed by two days. What would be your best approach to testing the aggregated results?

13) In a telecom ETL project, call records are transformed into summarized reports by area codes. Recently, new area codes were introduced. How would you validate that new area codes are handled correctly?

14) A manufacturing company’s ETL process integrates production data from multiple plants, each with unique product IDs. How would you ensure product IDs are consistent in the central data warehouse?

15) An ETL job is supposed to clean and load sensor data every hour. Due to network issues, some data fails to load occasionally. What’s the best way to test for data continuity?