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 Joins and Subqueries
00:00
5 left

SQL Joins and Subqueries

MediumSQL · PostgreSQL

Problem

Write a simple SQL query involving JOINs and subqueries.

Use the provided customer, policy, and claim tables. Return customers whose total approved claim amount is greater than the average approved claim amount across all approved claims.

Output

  1. One row per qualifying customer
  2. Columns: customer_id, customer_name, total_approved_claims
  3. Sort by total_approved_claims descending, then customer_id ascending

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer name
policies
ColumnTypeDescription
policy_idPKINTUnique policy identifier
customer_idINTCustomer who owns the policy
policy_numberVARCHAR(30)Business policy number
policy_statusVARCHAR(20)Current policy status
claims
ColumnTypeDescription
claim_idPKINTUnique claim identifier
policy_idINTPolicy associated with the claim
claim_statusVARCHAR(20)Current claim status
claim_amountDECIMAL(12,2)Claim amount
Tablescustomerspoliciesclaims
Interviewer

Your question is SQL Joins and Subqueries. Start with the requirements and the three 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.