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Customer Lifetime Value
Amazon's BI team builds a CLV (Customer Lifetime Value) table within their first week on the job — it's the foundation every downstream revenue model joins against. For each customer, return customer name, membership, total_orders, total_spent, and avg_order_value. Include customers with NO orders (show 0). Order by total_spent descending. CLV questions come up in virtually every Amazon BIE/DA screen because once you have this one table, you can answer 80% of follow-up questions ('top 10 buyers by membership,' 'CLV by signup cohort,' etc.).
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Schema
customers
| customer_id | name | signup_date | membership | total_orders | |
|---|---|---|---|---|---|
| 1 | John Smith | john.smith@email.com | 2023-01-15 | Gold | 15 |
| 2 | Emma Wilson | emma.wilson@email.com | 2023-03-20 | Silver | 8 |
| 3 | Michael Brown | michael.brown@email.com | 2023-02-10 | Gold | 12 |
orders
| order_id | customer_id | product | category | quantity | price | total | order_date | country | status |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 1 | Laptop Pro | Electronics | 1 | 1299.99 | 1299.99 | 2024-01-15 | USA | completed |
| 2 | 2 | Wireless Mouse | Electronics | 2 | 49.99 | 99.98 | 2024-01-16 | Canada | completed |
| 3 | 3 | Office Chair | Furniture | 1 | 349.99 | 349.99 | 2024-01-17 | USA | completed |
Expected output: total_orders: 3, total_spent: $150, avg_order_value: $50
Hint
Concepts
SELECT JOIN GROUP BY Aggregation ORDER BY Multiple JOINs + Aggregation
Practise the topic: SQL practice questions · JOIN practice · GROUP BY exercises · Advanced SQL interview questions
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Amazon · Apple · Revolut · Shopify · Snowflake · Stripe
A SQL Quest challenge matched to patterns reported for these companies — not a question any of them has published.
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