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Top 50 data extraction Interview Questions

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

50questions
~17htotal time
186companies covered
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1
null handlingStart here. 3 questions · ~60 min
SQL Query PracticeEasy
Practice
Recently asked

Return the second-highest distinct non-null salary from a single employee table.

null handlingsqldatabase queryingBBureau VeritasPayUItc Infotech
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2
Joins9 questions · ~180 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
SQL Extraction With JoinsHard
Practice
Recently asked

Extract filtered monthly category revenue and prior-period changes using joins, aggregations, and LAG.

JoinssqlAggregationsInc.VisaInc. In
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3
Date Functions7 questions · ~140 min
Top 5% Clients by VolumeMedium
Practice
Recently asked

Write a query to identify the top 5% of clients by transaction volume over the last quarter. Treat transaction volume as the number of transactions. Use t...

Date Functionssql querytransaction volumeHHighRadiusTTBO tekAirwallex Pty
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4
Data Manipulation7 questions · ~140 min
Split String to RowsEasy
Practice

Split each input string into one ordered row per character while excluding NULL and empty inputs.

Data Manipulationdata validationdata extractionWalmart LabsWalmart
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5
Window Functions6 questions · ~120 min
Finding Second-Highest ValuesMedium
Practice
Recently asked

Find the second-highest distinct non-NULL salary using PostgreSQL window-function logic.

Window FunctionsSubqueriesnull handlingAAccenture EspañaEErnst & Young U.S. LLPLLSEG (London Stock Exchange Group)
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6
data parsing3 questions · ~60 min
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7
More topics15 questions · ~300 min
Data Visualization TechniquesMedium
Practice

Create monthly, region-level metrics suitable for data visualization using SQL joins, date handling, and aggregation.

analytics toolspresentationdata visualizationWalmart Global TechExperian HealthFIRSTNET GLOBAL
Data into SnowflakeMedium
Practice
Recently asked

Summarize Snowflake ingestion activity by source system and load method.

data migrationdata ingestiondata validationSnowflakeSnowflake Computing
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