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Customer Retention Cohort
Build a simple retention cohort. For each customer, find their first order month (cohort_month). Then count how many customers from each cohort placed at least one order in each subsequent month. Show cohort_month, order_month, customers_active, and retention_rate (percentage of original cohort still active, rounded to 1 decimal). Sort by cohort_month, order_month. Retention cohorts are the gold standard of product analytics at Meta and Netflix.
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Schema
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: cohort: Jan, month: Feb, retention_rate: 60.0
Hint
Concepts
SELECT CTE MIN Date Functions GROUP BY JOIN DISTINCT CTE + Window Functions
Practise the topic: SQL practice questions · CTE practice · GROUP BY exercises · Date function practice · JOIN practice · Advanced SQL interview questions
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