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
Top Pipelines by Volume
00:00
5 left

Top Pipelines by Volume

MediumSQL · PostgreSQL

Problem

Write a query to identify the top three data pipelines by volume for each customer account over the last 30 days.

Use the run-level volume recorded in pipeline_runs and treat a NULL volume as zero. Include only pipelines with activity in the time period.

Output

  1. One row per qualifying account and pipeline, with at most three rows per account
  2. Columns: account_id, account_name, pipeline_id, pipeline_name, and total_volume_bytes
  3. Sort by account_id, then total volume descending, with pipeline_id ascending as the tie-breaker

Schema

customer_accounts
ColumnTypeDescription
account_idPKINTUnique customer account identifier
account_nameVARCHAR(100)Customer account name
pipelines
ColumnTypeDescription
pipeline_idPKINTUnique data pipeline identifier
account_idINTOwning customer account
pipeline_nameVARCHAR(120)Data pipeline name
pipeline_runs
ColumnTypeDescription
run_idPKINTUnique pipeline run identifier
pipeline_idINTPipeline executed by the run
completed_atTIMESTAMPTimestamp when the run completed
volume_bytesBIGINTBytes processed by the run
Tablescustomer_accountspipelinespipeline_runs
Interviewer

Your question is Top Pipelines by Volume. 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.