Dataford
Interview QuestionsInterview GuidesExperiencesCoaching
New
Pricing
Get started
Dataford
Popular roles
Software EngineerData AnalystData ScientistData EngineerBusiness AnalystAI EngineerMachine Learning EngineerProduct Manager
Browse
Browse All RolesEvery role hub, from analyst to MLBrowse All CompaniesCompany-specific interview loopsAll Interview GuidesThe full guide library
Top questions by role
Software EngineerData AnalystData ScientistData EngineerBusiness AnalystAI EngineerMachine Learning EngineerProduct Manager
Top questions by skill
SQLPythonStatisticsMachine LearningA/B TestingSystem DesignGenerative AIProduct SenseMetricsBehavioral
Browse all questions →Try a mock interview
Experiences
Practice
Mock InterviewsTimed interview simulations with feedbackCoaching1:1 coaching with people at your target companiesSuccess PathYour 6-week structured planModulesCurated lessons by topicWebinarsTalks from ex-Big Tech data leadsPlaygroundA free-form scratch editor
Learn
BlogInterview strategy and career adviceTech Job Market ReportHiring trends across data and AI rolesFor UniversitiesDataford for career centersAbout DatafordWho we are and how we build
Pricing
Build my plan
SQL Query From Scenario
00:00
5 left

SQL Query From Scenario

MediumSQL · PostgreSQL

Problem

Tell me about a time you were given a data storage scenario and had to write a SQL query to produce a specific output.

For this exercise, use the supplied users and transactions tables. Write a query that returns users with at least two successful transactions.

Output

  1. One row per qualifying user with user_name, successful_transaction_count, and successful_transaction_amount
  2. Include only transactions whose status is SUCCESS
  3. Sort by total amount descending, then user_id ascending for ties

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User display name
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTUser associated with the transaction
statusVARCHAR(20)Transaction processing status
amountNUMERIC(12,2)Transaction amount
Tablesuserstransactions
Interviewer

Your question is SQL Query From Scenario. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

You need to log in / sign up to run or submit.
CodePostgreSQL
Sign up free to run your codeLog inLn 1
Run your query to see results here.