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SQL Top 3 Per Country
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SQL Top 3 Per Country

MediumSQL · PostgreSQL

Problem

Write an SQL query using window functions to rank users by revenue within each country and return the top 3 users per country.

Use the provided users and transactions tables. Include tied users when they share a qualifying rank.

Output

  1. One row per qualifying user.
  2. Columns: user_id, user_name, country, total_revenue, and revenue_rank.
  3. Include users with ranks 1 through 3, ordered by country, rank, and user ID.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User display name
countryVARCHAR(2)Two-letter country code
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTUser associated with the transaction
revenueDECIMAL(12,2)Revenue generated by the transaction
Tablesuserstransactions
Interviewer

Your question is SQL Top 3 Per Country. Start with the requirements and the two tables in the Question tab.

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CodePostgreSQL
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