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Rank Users With SQL Window Functions

EasySQL · PostgreSQL00:00
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Your question is Rank Users With SQL Window Functions. Start with the requirements and the two tables on the right.

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Problem

Basis Technologies wants to compare user revenue performance across countries in Basis DSP. Write a PostgreSQL query that aggregates credited revenue per user and ranks users against others in the same country.

Requirements

  1. Include every user, including users with no credited revenue.
  2. Calculate each user's total credited revenue.
  3. Rank users within each country by total revenue in descending order. Users with tied revenue must receive the same rank.
  4. Return results ordered by country, rank, and user ID.

Schema

users
ColumnTypeDescription
user_idPKINTEGERUnique user identifier
user_nameVARCHAR(100)User display name
countryVARCHAR(2)Two-letter user country code
revenue_events
ColumnTypeDescription
event_idPKINTEGERUnique revenue event identifier
user_idINTEGERUser associated with the revenue event
amountNUMERIC(12,2)Revenue amount
event_statusVARCHAR(20)Revenue event processing status
Tablesusersrevenue_events
Your solutionPostgreSQL
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