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Analyze Customer Purchase Trends with Window Functions

MediumSQL · PostgreSQL00:00
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Welcome to the SQL screen.

The question is on your right: Analyze Customer Purchase Trends with Window Functions. Read through the requirements and the two tables first.

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Problem

An online retail company wants to analyze customer spending trends over months. Write a SQL query to calculate the total spending for each customer by month, along with the cumulative spending for each customer over time.

Requirements

  1. Join the customers and orders tables on customer_id.
  2. Group the results by customer and month of the order date.
  3. Calculate total spending per customer per month.
  4. Use a window function to calculate cumulative spending for each customer.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique identifier for each customer
customer_nameVARCHAR(255)Name of the customer
orders
ColumnTypeDescription
order_idPKINTUnique identifier for each order
customer_idINTIdentifier linking to the customer who made the order
order_dateDATEDate when the order was placed
amountDECIMAL(10,2)Total amount of the order
Tablescustomersorders
Your solutionPostgreSQL
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