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Rank Top 3 Users Per Region

EasySQL · PostgreSQL00:00
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Your question is Rank Top 3 Users Per Region. Start with the requirements and the two tables on the right.

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Problem

Chevron's analytics team wants to identify the highest-revenue users in each operating region. Write a PostgreSQL query that aggregates transaction revenue by user, ranks users within their region, and returns the top three users per region.

Requirements

  1. Include users with no transactions and treat their revenue as zero.
  2. Aggregate all transaction rows for each user before ranking.
  3. Use a window function to rank users independently within each region.
  4. Return the top three users per region, breaking revenue ties by ascending user_id.

Schema

users
ColumnTypeDescription
user_idPKINTEGERUnique user identifier
full_nameVARCHAR(100)User's full name
region_nameVARCHAR(50)Chevron operating region
transactions
ColumnTypeDescription
transaction_idPKINTEGERUnique transaction identifier
user_idINTEGERUser associated with the transaction
revenueNUMERIC(12,2)Revenue attributed to the transaction
transaction_dateDATETransaction date
Tablesuserstransactions
Your solutionPostgreSQL
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