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SQL for Repeat Customers
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SQL for Repeat Customers

MediumSQL · PostgreSQL

Problem

Affirm wants to identify customers who completed multiple purchases through Affirm Checkout during the 12 months ending 2025-01-15. Write a PostgreSQL query that returns one row per qualifying customer.

Requirements

  1. Include only purchases with status = 'completed' from 2024-01-15 through 2025-01-15, inclusive.
  2. Return the customer ID, customer name, number of completed purchases, total purchase amount, and most recent purchase date.
  3. Include only customers with at least two qualifying purchases.
  4. Sort by purchase count descending, total purchase amount descending, and customer ID ascending.

Schema

customers
ColumnTypeDescription
customer_idPKINTEGERUnique customer identifier
customer_nameVARCHAR(100)Customer's display name
emailVARCHAR(255)Customer email address
purchases
ColumnTypeDescription
purchase_idPKINTEGERUnique purchase identifier
customer_idINTEGERCustomer associated with the purchase
purchase_dateDATEDate the purchase was submitted
amountNUMERIC(10,2)Purchase amount
statusVARCHAR(20)Purchase processing status
Tablescustomerspurchases
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