Table 1: msft_customers
Contains details about customers, including their ID, name, age, gender, and the date they joined.
customer_id: int, name: varchar, age: int, gender: varchar, join_date: date
Question 218
Total Amount Spent by Each Customer
Write a SQL query to find the total amount spent by each customer. Include the customer's name and the total amount spent.
Hint: Join the customer and transaction tables and use aggregation functions.
Table 2: msft_products
Holds information on products, such as product ID, name, price, and category.
product_id: int, product_name: varchar, price: decimal, category: varchar
Table 3: msft_sales
Records details of sales transactions, including the sale ID, customer ID, product ID, date of the transaction, and the quantity of products sold.
sale_id: int, customer_id: int, product_id: int, sale_date: date, quantity: int
Solution
postgres
SELECT c.customer_id, c.name, SUM(p.price * s.quantity) AS total_spent
FROM msft_sales s
JOIN msft_customers c ON s.customer_id = c.customer_id
JOIN msft_products p ON s.product_id = p.product_id
GROUP BY c.customer_id, c.name;
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