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practice-01.sql
RunSELECT city, COUNT(*) AS orders
FROM customers
WHERE signup_year = 2025
GROUP BY city
ORDER BY orders DESC
LIMIT 5;Result
5 rowsPassed 2/2
| city | orders |
|---|---|
| Hà Nội | 128 |
| TP. Hồ Chí Minh | 112 |
| Đà Nẵng | 64 |
| Cần Thơ | 31 |
| Hải Phòng | 28 |
Your first SQL query
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Explore the pack- 0130 beginner SQL questions30 exercises · BeginnerSELECT, WHERE, ORDER BY, GROUP BY and JOIN on a retail dataset.
- 02RFM and customer segments12 exercises · IntermediateCompute Recency, Frequency and Monetary, then group customers by behaviour.
- 03Cohorts and churn12 exercises · AdvancedMeasure retention by signup cohort and spot early signs of churn.
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