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Top 41
Prep plan
Updated weekly · Last refresh Aug 30

Inc. Data Engineer Interview Questions

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

41questions
~6htotal time
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1
SQL & Data ManipulationStart here. 8 questions + 2 drills · ~88 min
Monthly Sales Trends by CategoryMedium
Practice

Aggregate monthly sales by product category and use LAG to calculate month-over-month changes.

InfrastructureToolsData WranglingInc.
Top Earners Per DepartmentMedium

Tests window function proficiency and correct ranking per group in SQL.

Window FunctionsRankingGroup ByInc.
DAU With Three Consecutive DaysHard

Tests SQL skills with CTEs, date logic, and consecutive-day user activity patterns.

SubqueriesDate FunctionsCTEsInc.
Top Customers SQL QueryEasy
Practice
Practice drill

Aggregate customer sales volume and return Pyramid Consulting's top 10 customers in descending order.

RankingGroup ByAggregationsPyramid ConsultingBNYCambia Health Solutions
SQL Top 10 Products by SalesEasy
Practice
Practice drill

Aggregate completed SMX product sales and return the top 10 products by units sold.

RankingGroup ByAggregationsSMXBellEaze
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2
Pipelines10 questions · ~84 min
Design High-Throughput Event PipelineHard

Design a real-time event pipeline that can handle millions of events per second with sub-second latency.

data pipelineevent processinglatencyInc.
Unix Archive Recent FilesEasy

Tests practical command-line skills for file handling in data engineering workflows.

InfrastructureBatch ProcessingAutomationInc.
Real-Time Streaming Pipeline DesignHard

Tests streaming architecture choices and strategies for late data handling in production pipelines.

Stream ProcessingDependenciesBackfillingInc.
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3
Coding4 questions · ~34 min
Flatten Nested JSON in PythonMedium

Tests data parsing and schema design for turning nested JSON into load-ready structures.

deduplicationStringsfunctionsInc.
PySpark Wide Join With Schema FixesHard

Tests PySpark proficiency for joining at scale, schema reconciliation, and wide transformations.

JoinsData WranglingsparkInc.
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4
Behavioral & Leadership19 questions · ~160 min
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The finish line: interview-readyComplete all 41 questions plus 2 hands-on drills to finish this plan.