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SQL Top Watch Time by Month
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SQL Top Watch Time by Month

MediumSQL · PostgreSQL

Problem

Disney+ France wants to identify its most engaged viewers each month. Write a PostgreSQL query to find the top three users by total watch time for every calendar month.

Requirements

  1. Join users with watch_events using the user identifier.
  2. Aggregate watch time by calendar month and user. Treat NULL watch_seconds values as zero.
  3. Rank users independently within each month and return only the top three, ordered by month and rank.

Schema

users
ColumnTypeDescription
user_idPKINTEGERUnique Disney+ subscriber identifier
user_nameVARCHAR(100)Subscriber display name
country_codeCHAR(2)Subscriber country code
watch_events
ColumnTypeDescription
event_idPKINTEGERUnique viewing event identifier
user_idINTEGERUser associated with the viewing event
watched_atTIMESTAMPViewing event start timestamp
watch_secondsINTEGERNumber of seconds watched
Tablesuserswatch_events
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