Dataford
Top 50
Topic roadmap
Updated weekly · Last refresh Sep 13

Top 50 Data Manipulation Interview Questions

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

50questions
~17htotal time
149companies covered
Track your progressSign up free to work through all 50 questions and resume where you left off.
Start practicing free →
1
SQL & Data ManipulationStart here. 41 questions · ~857 min
SQL Query for Data ExtractionEasy
Practice
Recently asked

Extract qualifying market observations by venue and price, then return them in chronological order.

JoinsData ManipulationGroup ByEquifaxDPR ConstructionRigUp
Second and Nth Highest ValuesMedium
Practice
Recently asked

Find the second highest distinct salary and adapt the query to retrieve any requested salary rank.

Data Manipulationsqldatabase queryingSnowflake ComputingKKGISLAARi
Truncate vs DeleteMedium
Practice
Recently asked

Explain how TRUNCATE and DELETE differ in row removal, transaction behavior, and identity handling.

database managementData Manipulationdata managementCCitiusTechArcesiumDDatamatics Global Services
SQL Rolling Average WindowEasy
Practice

Calculate monthly IRS return processing averages and three-month rolling averages with a window function.

Data ManipulationIRSGrubMarketOrbital Insight
Rolling Average Over Last 30 DaysMedium
Practice

Calculate each customer's 30-day rolling engagement average using a PostgreSQL window function.

Date FunctionsData ManipulationAggregationsTTecholutionSSignifyAAman
Rolling 30-Day Transaction AverageMedium
Practice
Recently asked

Calculate each Scotiabank customer's rolling 30-day transaction average using PostgreSQL window functions and date-based frames.

Window FunctionsData ManipulationsqlSScotiabankAscendionLendbuzz
Window Functions Rolling ComparisonHard
Practice

Compute each user's seven-day activity average and compare it with the corresponding rolling average from the prior week.

Window FunctionsLag/LeadData ManipulationFactoredCContentsquareCCult (Cure.fit)
Rolling 7-Day Average by RegionMedium
Practice

Calculate each product-region's rolling 7-day average sales using daily aggregation and calendar-aware windowing.

Window FunctionsDate FunctionsData ManipulationBayerCCoca-Cola Beverages SingaporeTTesco
More SQL & Data Manipulation questions with a free account

Sign up to see every question

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

Get my prep plan
2
Coding9 questions · ~188 min
More Coding questions with a free account
The finish line: interview-readyComplete all 50 questions to finish this plan.