Determine the average order value for customers located in the United States who have made 3 or more orders within the last month, using data from the "orders" and "customers" tables. Use a join operation in your query.

Question Analysis

The question is asking us to calculate the average order value for a specific subset of customers. We need to focus on customers located in the United States who have placed 3 or more orders in the last month. This involves two tables: "orders" and "customers".

• Customers Table: This table likely contains information about each customer, including their location.
• Orders Table: This table likely includes details about each order, such as the customer ID, order date, and order value.

The task requires:

1. Identifying customers from the United States.
2. Filtering these customers to include only those with 3 or more orders in the last month.
3. Calculating the average order value for these customers.

We will need to use a SQL query with a join operation to combine data from the "orders" and "customers" tables and perform the necessary calculations.

Answer

SELECT AVG(order_value) AS average_order_value
FROM (
    SELECT o.customer_id, SUM(o.order_value) / COUNT(o.order_id) AS order_value
    FROM orders o
    JOIN customers c ON o.customer_id = c.customer_id
    WHERE c.location = 'United States'
      AND o.order_date >= DATEADD(month, -1, GETDATE())
    GROUP BY o.customer_id
    HAVING COUNT(o.order_id) >= 3
) AS filtered_orders;

Explanation:

• JOIN: We join the "orders" table with the "customers" table on the customer ID to get location data for each order.
• WHERE Clause: We filter for orders by customers located in the United States and orders placed within the last month.
• GROUP BY and HAVING: We group the results by customer ID and use the HAVING clause to ensure we only consider customers with 3 or more orders.
• AVERAGE Calculation: We calculate the average order value for each customer in the subquery and then compute the overall average from these results.

This query will provide the average order value for customers meeting the specified criteria.