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Top 10 Users by Watch Time
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Top 10 Users by Watch Time

MediumSQL · PostgreSQL

Problem

Disney+ Hotstar wants to identify its most engaged users in India. Write a PostgreSQL query that ranks users by total watch time during January 2025.

Requirements

  1. Restrict users to the IN region and sessions starting from 2025-01-01 through 2025-01-31.
  2. Calculate total watch time in seconds for each Indian user, treating users with no matching sessions as having zero watch time.
  3. Return the top 10 users, ordered by total watch time descending and user_id ascending to break ties.

Schema

users
ColumnTypeDescription
user_idPKINTEGERUnique user identifier
display_nameVARCHAR(100)User display name
regionVARCHAR(10)User region code
watch_sessions
ColumnTypeDescription
session_idPKBIGINTUnique viewing session identifier
user_idINTEGERUser associated with the session
started_atTIMESTAMPSession start timestamp
watch_secondsINTEGERNumber of seconds watched
Tablesuserswatch_sessions
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