Top 19
Prep plan
Updated weekly · Last refresh Aug 30

One Data Analyst Interview Questions

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

19questions
~3htotal time
Track your progressSign up free to work through all 19 questions and resume where you left off.
Start practicing free →
1
SQL & Data ManipulationStart here. 5 questions + 1 drill · ~56 min
Second-Highest Transaction Amount QueryMedium
Practice

Find the second-highest distinct transaction amount using a subquery in PostgreSQL without LIMIT.

SubqueriesRankingsalaryOne
7-Day Rolling DAU on FacebookMedium
Practice

Compute daily distinct active users and a 7-day rolling average using a CTE and window function.

One
Explain Full Outer vs Left JoinMedium

Explain how FULL OUTER JOIN and LEFT JOIN differ when reconciling customer records across systems.

JoinsData WranglingCase WhenOne
Window Ranking in Ticket QueuesMedium

Explain SQL window functions and when to use ROW_NUMBER() versus DENSE_RANK() for ranked ticket analysis.

Window FunctionsRankingrow_numberOne
Top Customers by Region VolumeMedium
Practice
Practice drill

Find the top 3 customers in each region by transaction volume using joins, aggregation, and window ranking.

Window FunctionsJoinsRankingJPMorganChaseSilicon Valley BankNavi
More SQL & Data Manipulation questions with a free account
2
Pipelines4 questions · ~37 min
Version Control for Code and DataEasy

Explain how to version pipeline code and datasets so teams can collaborate, reproduce results, and track changes safely.

Data QualityToolsversion controlOne
Incremental vs Full RefreshMedium

Tests incremental modeling strategy and performance versus correctness trade-offs.

Data ModelingOne
Schema Tests and AssertionsMedium

Tests data quality testing practices and how you operationalize them in pipelines.

Data QualityAutomationQualityOne
More Pipelines 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
3
Behavioral & Leadership10 questions · ~93 min
Sustaining Team Motivation Over TimeEasy

Tests whether you can sustain morale and execution during a prolonged, difficult effort without losing focus, accountability, or team trust.

CommunicationLeadershipOwnershipOne
More Behavioral & Leadership questions with a free account
The finish line: interview-readyComplete all 19 questions plus 1 hands-on drill to finish this plan.