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Movie Title Initial Letter Histogram (SUBSTR)
A library-style index wants a histogram of movie titles by their first letter. Group movies by UPPER(SUBSTR(title, 1, 1)) so 'a' and 'A' bucket together.
Show initial and movie_count. Order by initial.
The UPPER is a defensive normalization — most titles start with capitals, but mixed casing in source data is the kind of subtle bug that shows up in production after a content team imports something messy.
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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: A → 2, B → 1
Hint
SELECT, GROUP BY, SUBSTR, and open the hint there if you stall.Concepts
SELECT GROUP BY SUBSTR String Functions
Practise the topic: SQL practice questions · GROUP BY exercises · String function practice
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