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Top 50 Self-Joins Interview Questions

The most frequently asked Self-Joins questions across all roles and companies, ranked by real interview frequency. Updated daily.

50questions
~10htotal time
235companies covered
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1
SubqueriesStart here. 5 questions · ~60 min
Second Highest Without AggregatesHard
Practice
Recently asked

Find the second highest salary in each department without using aggregate functions.

SubqueriesRankingSelf-JoinsCredit GenieCisco Restaurant + BarDevoteam
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2
Date Functions3 questions · ~36 min
Compare Region Performance Across MonthsMedium
Practice
Recently asked

Use a self-join to compare each region's monthly orders and revenue against its prior month.

Date FunctionsSelf-JoinsAggregationsairtelInstacart
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3
Joins29 questions · ~350 min
Employees Earning More Than ManagersEasy
Practice
Recently asked

Use a self-join to find Arcesium employees whose salaries exceed their direct managers' salaries.

JoinsSelf-JoinsArcesiumCATERPILLAR
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4
Window Functions7 questions · ~85 min
Detect Overlapping Subscription PeriodsHard
Practice

Find overlapping subscription periods for each customer account using window functions and date comparisons.

Window FunctionsDate FunctionsSelf-JoinsRipplingKraken
Three-Day Chime Login StreaksHard
Practice

Use CTEs and window functions to count Chime users with a login streak of exactly three consecutive days.

Window FunctionsDate FunctionsCTEsChime
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5
More topics6 questions · ~72 min
Duplicate Transactions QueryMedium
Practice
Recently asked

Identify near-duplicate Mastercard authorizations with a self-join and rank matching transactions within two minutes.

Self-JoinssqlMastercardBank Of America Merrill LynchPitchbook Data
Monthly Retention CohortsHard
Practice
Recently asked

Measure monthly user retention with a self-join and conditional aggregation across Bain & Company platform activity.

Self-JoinssqlBain &SASItc Infotech
Identify Duplicate Accounts by Shared Identity FieldsMedium
Practice

Find duplicate accounts by grouping on identity fields and flagging repeated account records.

Data WranglingSelf-JoinsAggregationsWhatnot
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