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SQL Top Spenders With Recent Logins
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SQL Top Spenders With Recent Logins

MediumSQL · PostgreSQL

Problem

Given a table of user transactions and a table of user logins, write a query to identify the top 10% of users by spend who have logged in within the last 30 days.

Use CURRENT_DATE as the reference date. Treat a user's spend as the sum of their transaction amounts, and rank all users with transactions before selecting users in the top decile.

Output

  1. One row per qualifying user with user_id, total_spend, and last_login_at.
  2. Include only users in the top 10% by total spend who logged in within the last 30 days.
  3. Sort by total_spend descending, then user_id ascending.

Schema

user_transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTUser who made the transaction
amountNUMERIC(12,2)Transaction amount included in user spend
transaction_atTIMESTAMPTimestamp when the transaction occurred
user_logins
ColumnTypeDescription
login_idPKINTUnique login event identifier
user_idINTUser associated with the login
login_atTIMESTAMPTimestamp when the user logged in
Tablesuser_transactionsuser_logins
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