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GROUP BY Basics
Count how many movies exist in each genre. Show genre and movie_count. Sort by movie_count descending to see the most popular genres first.
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Schema
movies
| id | title | year | genre | rating | votes | revenue_millions | runtime | director |
|---|---|---|---|---|---|---|---|---|
| 1 | Guardians of the Galaxy | 2014 | Action | 8.1 | 757074 | 333.13 | 121 | James Gunn |
| 2 | Prometheus | 2012 | Adventure | 7 | 485820 | 126.46 | 124 | Ridley Scott |
| 3 | Split | 2016 | Horror | 7.3 | 157606 | 138.12 | 117 | M. Night Shyamalan |
Expected output: Genre names with their movie counts, sorted
Hint
GROUP BY genre creates one row per genre. COUNT(*) counts movies in each group. ORDER BY movie_count DESC sorts largest first.
Concepts
SELECT GROUP BY Aggregation
Practise the topic: SQL practice questions · GROUP BY exercises
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