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SQL for Repeat Purchase Rate
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SQL for Repeat Purchase Rate

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the repeat purchase rate of customers who bought a specific skincare product within 30 days of their initial purchase. Use the Sephora product named Hydrating Facial Mask and treat a repeat as another purchase of that same product within 30 calendar days.

Output

  1. One row for the product, with product_name, initial_customers, repeat_customers, and repeat_purchase_rate.
  2. Return the rate as a percentage rounded to two decimal places.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer display name
emailVARCHAR(255)Customer email address
products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(150)Product name
categoryVARCHAR(80)Merchandising category
descriptionTEXTProduct description
orders
ColumnTypeDescription
order_idPKINTUnique order identifier
customer_idINTCustomer who placed the order
order_dateDATEDate the order was placed
order_statusVARCHAR(30)Order fulfillment status
order_items
ColumnTypeDescription
order_item_idPKINTUnique order-line identifier
order_idINTRelated order
product_idINTPurchased product
quantityINTUnits purchased
Tablescustomersproductsordersorder_items
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Your question is SQL for Repeat Purchase Rate. Start with the requirements and the four tables in the Question tab.

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CodePostgreSQL
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