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Quality Grade Distribution
How many products are in each quality grade (L=low, M=medium, H=high)? Show type, product_count. Order by product_count descending.
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Schema
products
| udi | product_id | type | tool_wear_min |
|---|---|---|---|
| 5640 | L52819 | L | 180 |
| 2171 | M17030 | M | 10 |
| 228 | L47407 | L | 168 |
Expected output: Per-grade product counts
Hint
GROUP BY type with COUNT(*).
Concepts
SELECT GROUP BY Aggregation
Practise the topic: SQL practice questions · GROUP BY exercises
Read the concept: How to find duplicates in SQL
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