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Top 50 Data Wrangling Interview Questions

The most frequently asked Data Wrangling questions across all roles and companies, ranked by real interview frequency. Updated daily.

50questions
~17htotal time
198companies covered
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1
SQL & Data ManipulationStart here. 46 questions · ~938 min
SQL vs NoSQL DifferencesEasy
Practice
Recently asked

Query a comparison table to present the key structural and operational differences between SQL and NoSQL databases.

nosqlJoinsData WranglingCogitoRamsey SolutionsPyramid Consulting
Find Duplicate Records in SQLEasy
Practice
Recently asked

Use GROUP BY and HAVING to find duplicate patient records in a Johns Hopkins Medicine dataset.

Data WranglingGroup ByHavingEmersonCareDxSberbank
Top Customers by Net SalesMedium
Practice
Recently asked

Compute top 10 customers by net sales using joins and aggregations, ordering by revenue with deterministic tie-breaking.

SubqueriesJoinsData WranglingGain DigitalTCSZest AI
Monthly Sales Trends by CategoryMedium
Practice

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

InfrastructureToolsData WranglingTotal Wine & MoreInc.Benjamin Moore
Find Duplicates With SQLEasy
Practice

Find repeated non-null customer emails in Nagarro onboarding data using GROUP BY and HAVING.

Data WranglingGroup ByAggregationsInformaticaChetuBJC HealthCare
Monthly Campaign Performance SummaryEasy
Practice

Aggregate January 2024 campaign data by channel using GROUP BY, filtering, and ordering by total clicks.

JoinsData WranglingAggregationsDNVEversanaDiscord
SQL Join Matching RowsEasy
Practice

Filter Revature assessment records to find candidates who passed SQL Fundamentals, then sort the matching rows by candidate name.

SubqueriesJoinsData WranglingIncedoCloudFactoryRevature
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2
Coding4 questions · ~82 min
Merge Overlapping Trade IntervalsEasy
Practice

Merge overlapping time intervals for trade activity using sorting and greedy scanning.

ArraysData WranglingSortingRobinhoodPoint72Coinbase
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