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Year-over-Year Movie Rating Trends
Analyze year-over-year trends in movie quality. For each year, show year, num_movies, avg_rating (2 dec), prev_year_avg (LAG), and rating_change (difference from previous year, 2 dec). Sort by year. YoY comparison with LAG is one of the most common analytical patterns at every data-driven company.
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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: rating_change: -0.40
Hint
Concepts
SELECT Window Functions LAG GROUP BY CTE
Practise the topic: SQL practice questions · Window function practice · GROUP BY exercises · CTE practice · Advanced SQL interview questions
In these company practice sets
Airbnb · Anthropic · Apple · Databricks · NVIDIA · Netflix · Snowflake · Spotify · Tesla
A SQL Quest challenge matched to patterns reported for these companies — not a question any of them has published.
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