All problems

Genre Engagement

mediumSQLJoinsGroupBy

The StreamVerse acquisitions team buys by genre, not by title, so a per-show leaderboard is the wrong resolution for them. They want to see attention pooled by genre — and the genre label is not on the session log at all.

watch_events — one row per watch session: one sitting in which one subscriber watched one show. subscriber_id points at a row in subscribers, show_id at a row in shows, and watch_minutes is how long that sitting lasted. The same person can appear many times.

id subscriber_id show_id watch_minutes watch_date
1 1 1 45 2023-05-01
2 1 5 60 2023-05-03
3 2 3 20 2023-05-02
4 3 2 55 2023-05-05
5 4 1 40 2023-05-06
6 4 4 70 2023-05-08
7 1 3 25 2023-05-10
8 3 5 50 2023-05-11
9 2 2 30 2023-05-12
10 5 4 65 2023-05-14

shows — one row per title in the catalogue. genre is a single label such as sci-fi or drama; release_year is the year the title came out.

id title genre release_year
1 Nebula Drift sci-fi 2021
2 The Long Kitchen drama 2019
3 Byte Size comedy 2022
4 Deep Trench documentary 2020
5 Neon Alley sci-fi 2023

Both tables already exist in the database — there is nothing to create or load.

Task: Write a query that returns two columns, genre and minutes, one row per genre that has been watched at least once, minutes being the total watch_minutes across all shows in that genre. Most minutes first; two genres on the same total come back in alphabetical order of genre.

Example output

Shape only — these genres and figures are invented:

genre minutes
thriller 2400
romance 1150
horror 860
western 310

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