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Rolling Transaction SQL and Ranking

HardSQL · PostgreSQL00:00
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Your question is Rolling Transaction SQL and Ranking. Start with the requirements and the two tables on the right.

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Problem

Write an SQL query using window functions to calculate each user's 7-day rolling average transaction amount and rank users within each day by total spend. Use the users and transactions tables. Include users with transactions in the output and calculate the rolling average over calendar days, including the current day.

Output

  1. One row per user and day with at least one transaction
  2. Columns: user_id, activity_date, daily_total_spend, rolling_7_day_avg_transaction_amount, and daily_spend_rank
  3. Sort by activity_date, daily_spend_rank, then user_id

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
display_nameVARCHAR(100)User display name
emailVARCHAR(255)User email address
transactions
ColumnTypeDescription
transaction_idPKINTUnique transaction identifier
user_idINTUser who made the transaction
transaction_dateDATECalendar date of the transaction
amountNUMERIC(12,2)Transaction amount
Tablesuserstransactions
Your solutionPostgreSQL
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