WNS Data Engineer Interview Questions

The questions to prepare for a WNS Data Engineer interview. Questions from real interview reports rank first. Updated daily.

3questions

~1htotal time

Track your progressSign up free to work through all 3 questions and resume where you left off.

PipelinesStart here. 2 questions · ~16 min

Explain how you would design, implement, validate, orchestrate, and monitor an ETL pipeline from scratch.

Data Quality and Schema EvolutionMedium

Approach for handling schema changes and data quality checks in a high-volume data lake pipeline.

schema evolutionData ModelingQuality

WNS

SQL & Data Manipulation1 question + 3 drills · ~38 min

Assesses practical SQL and Python skills for data transformation work.

Find the second highest distinct salary from a single table using basic PostgreSQL ordering and limiting.

Find the second highest salary in each department without using aggregate functions.

Standardize missing observation fields with fallback values, missingness flags, and ordered output.

Create a free account to unlock this list and practice real interview questions.

The finish line: interview-readyComplete all 3 questions plus 3 hands-on drills to finish this plan.