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Top Failed Payments in Rolling Window
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Top Failed Payments in Rolling Window

HardSQL · PostgreSQL

Problem

Write a SQL query to find the top 5 user accounts with the highest number of failed payment attempts within a rolling 10-minute window at Affirm.

Use the provided account and payment-attempt data. Consider only failed attempts. Return one row per account, selecting the latest window when an account has multiple windows with the same maximum count.

Output

  1. Columns: user_account_id, max_failed_attempts_10m, window_start, and window_end
  2. One row per account, limited to the top 5 accounts
  3. Sort by max_failed_attempts_10m descending, then user_account_id ascending

Schema

user_accounts
ColumnTypeDescription
user_account_idPKINTUnique Affirm user account identifier
account_typeVARCHAR(30)Account classification
payment_attempts
ColumnTypeDescription
payment_attempt_idPKINTUnique payment attempt identifier
user_account_idINTAccount associated with the payment attempt
attempted_atTIMESTAMPTimestamp when the payment attempt occurred
is_failedBOOLEANWhether the payment attempt failed
failure_reasonVARCHAR(40)Optional reason for a failed attempt
Tablesuser_accountspayment_attempts
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Your question is Top Failed Payments in Rolling Window. Start with the requirements and the two tables in the Question tab.

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