ETL Testing ETL Testing Tools and Automation 3

Question 1

Which Informatica feature is primarily used by ETL testers to validate data flows and transformation logic in Informatica PowerCenter?

Accepted Answer

Informatica Data Quality (IDQ) rules and mapplets

Answer

Informatica Data Quality rules and mapplets allow testers to embed data quality checks directly into PowerCenter mappings to validate transformation outputs.

Question 2

What is 'test data management' (TDM) in the context of ETL testing?

Accepted Answer

The discipline of creating, masking, provisioning, and maintaining test datasets that accurately represent production data without exposing PII

Answer

TDM ensures ETL test environments have realistic, safe, and sufficient data by masking PII from production copies or generating synthetic equivalents.

Question 3

In ETL testing automation, what is the benefit of using version-controlled ETL test scripts stored in Git?

Accepted Answer

It provides change history, enables team collaboration, and allows rollback of test logic changes

Answer

Storing ETL test scripts in Git provides full audit history, enables collaborative development, supports code review, and allows reverting to previous test versions if needed.

Question 4

Which Python library is widely used in US data engineering teams to write unit tests for PySpark ETL transformations?

Accepted Answer

PyTest with PySpark's local mode or Chispa for DataFrame assertions

Answer

PyTest combined with PySpark's local execution mode or the Chispa library allows engineers to write fast, isolated unit tests for Spark DataFrame transformation logic.

Question 5

What is 'observability' in the context of ETL pipeline testing and monitoring?

Accepted Answer

The ability to infer the internal state and health of an ETL pipeline from its external outputs, logs, and metrics

Answer

ETL observability means instrumented pipelines emit logs, metrics, and traces that allow engineers to diagnose failures, detect data quality degradation, and understand pipeline behavior without direct inspection.

ETL Testing - extract, transform, load Practice Test

ETL Testing - extract, transform, load Practice Test

ETL Testing ETL Testing Tools and Automation 3