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Top 50 data relationships Interview Questions

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

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SQL & Data ManipulationStart here. 49 questions · ~498 min
Find Inactive CustomersEasy
Practice

Find Flipkart customers with no orders in the prior six months using a LEFT JOIN and date-filtered aggregation.

data relationshipsuser retentionsql queriesFlipkartPNC Financial Services Group
Mutual Follows QueryMedium
Practice
Recently asked

Use a self-join to return each mutual follower pair once, with the lower user ID first.

data relationshipsnull handlingJoinsBee RoboticsSupermicro
First and Last Transaction Day PurchasesMedium
Practice
Recently asked

Use CTEs and conditional aggregation to find Meta users with at least three items on both their first and last transaction days.

data relationshipsJoinsAggregationsMeta
SQL Query for Team MatchesEasy
Practice
Recently asked

Pair every Pool A team with every Pool B team and format each matchup as Team A vs Team B.

data relationshipsJoinssqlAltimetrik
SQL Match Customers by CityMedium
Practice

Use a self-join to return unique pairs of customers who share the same non-null city and country.

data relationshipsnull handlingJoinsPhonepe
SQL: Parents With SiblingsEasy
Practice

Use joins and COUNT(DISTINCT) to find Janus Henderson Investors parents linked to multiple students.

data relationshipssqlJanus Henderson Investors
Find First Defect Created After Each DeploymentMedium
Practice

Use joins and ROW_NUMBER to find the earliest defect created after every deployment.

Window Functionsdata relationshipsDate FunctionsApex Systems
SQL Churn After First MonthMedium
Practice

Use monthly cohort logic to find users with no transaction in the calendar month after their first transaction month.

data relationshipsDate FunctionsCTEsServiceTitan
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