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Top Customers by Region Volume
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Top Customers by Region Volume

MediumSQL · PostgreSQL

Problem

Write a PostgreSQL query to return the top 3 customers by transaction volume in each region. Rank customers by total transaction count, break ties by higher total transaction amount, and then by lower customer_id.

Schema

Tables
  • customers
  • regions
  • transactions
Tablescustomersregionstransactions
Interviewer

Your question is Top Customers by Region 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.

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CodePostgreSQL
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