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Top 50 SQL Interview Questions

The most frequently asked questions on this topic across all roles and companies, ranked by real interview frequency. Updated weekly.

50questions
~7htotal time
2,354companies covered
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1
JoinsStart here. 21 questions · ~188 min
Customer Orders: LEFT vs INNER JOINEasy
Recently asked

Explain how INNER JOIN and LEFT JOIN differ, and when to use each for matched-only versus all-left-row analysis.

JoinsData WranglingGroup ByBMC SoftwareThe Home DepotMeta
Discuss Data Analysis Tooling ChoicesEasy
Recently asked

Explain how SQL fits with data analysis and visualization tools, and when to use each in an analytics workflow.

JoinsData WranglingAggregations360LearningNationwideUC Santa Barbara
SQL vs NoSQL for Go-to-Market DataEasy
Recently asked

Explain how SQL and NoSQL differ in schema, consistency, scaling, and Demandbase-style analytics use cases.

JoinsData WranglingZebra TechnologiesUniversity of ArkansasBuck
Clustered vs Non-Clustered IndexesMedium
Recently asked

Explain how clustered and non-clustered indexes differ in storage, lookup behavior, and query performance.

JoinsData WranglingAkamaiVerisk AnalyticsHewlett Packard Enterprise Development
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2
Data Wrangling9 questions · ~81 min
Handling Missing and Dirty SQL DataMedium
Recently asked

Explain how to profile, clean, and standardize missing or dirty data before analysis.

Data WranglingCase WhenQualitySamsung ElectronicsAmerican AirlinesUS Air Force
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3
Window Functions5 questions · ~45 min
Window Ranking in Ticket QueuesMedium
Recently asked

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

Window FunctionsRankingrow_numberXYZPDI SoftwareThe Cigna Group
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4
Tools3 questions · ~27 min
Explaining Visualization Tool ExperienceEasy
Recently asked

Explain how you use SQL analysis to build dashboards, choose visuals, and communicate insights to stakeholders.

ToolsData WranglingKohl'sHP SCDSTypeform
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5
Subqueries3 questions · ~27 min
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6
More topics9 questions · ~81 min
Analyze Customer Purchase Trends with Window FunctionsMedium
Practice
Recently asked

Calculate the monthly spending trends for customers using window functions and joins.

The Home DepotWorld Wide TechnologyHewlett Packard Enterprise
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