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Top 50 database querying Interview Questions

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

50questions
~17htotal time
110companies covered
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1
JoinsStart here. 7 questions · ~140 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
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2
Data Manipulation4 questions · ~80 min
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 ComputingKKGISLSBS
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3
Window Functions8 questions · ~160 min
Top N Per Group with WindowMedium
Practice

Use a window function to return the three highest-paid employees within each department.

Window FunctionsJoinsRankingInc.nferenceOptum
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4
postgresql5 questions · ~100 min
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5
Date Functions5 questions · ~100 min
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6
More topics21 questions · ~420 min
Second Highest Value SQLEasy
Practice
Recently asked

Use a scalar subquery and MAX to find the second distinct annual salary.

sql queryRankingdatabase queryingLLuxoft SingaporePCS Global TechAmazon Web Services
Nth Highest Salary QueryEasy
Practice
Recently asked

Find all active Freecharge employees at the third-highest distinct salary using DENSE_RANK and a department join.

sql querydatabase queryingFreechargeOptum TechBrillio
Debug and Optimize Slow SQLMedium
Practice

Explain how to diagnose a slow SQL query and improve its performance.

database optimizationlarge datasetsdatabase queryingCChildren's Cancer Research GroupBBoyd GamingAubay Spain
Indexing and Query PerformanceMedium
Practice

Write a selective PostgreSQL ticket query and explain how indexing can improve its filtering and sorting performance.

database optimizationJoinsData WranglingZendeskFactored
SQL: Second and Nth Highest SalaryMedium
Practice

Return employees tied at the second and fourth highest non-null salary levels using salary ranking.

sqldatabase queryingAggregationsNCR AtleosHashedIn by Deloitte
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