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Top Pipelines by Volume
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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
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