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Top Users by Region Query

MediumSQL · PostgreSQL00:00
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Your question is Top Users by Region Query. Start with the requirements and the two tables on the right.

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Problem

ResMed’s myAir analytics team wants to identify the highest-usage users in each geographic region. Write a PostgreSQL query that ranks users by their total completed therapy duration.

Requirements

  1. Join users to myair_usage_sessions using user_id.
  2. Include only sessions with session_status = 'completed' and a non-null, non-negative duration_minutes value.
  3. Calculate total usage duration for each user within each non-null region.
  4. Return the top 10 users per region, ranking ties deterministically by ascending user_id. Include the region, user ID, total duration, and regional rank.

Schema

users
ColumnTypeDescription
user_idPKINTEGERUnique myAir user identifier
regionVARCHAR(50)Geographic region assigned to the user
myair_usage_sessions
ColumnTypeDescription
session_idPKINTEGERUnique usage session identifier
user_idINTEGERAssociated user identifier
session_dateDATEDate on which the therapy session occurred
duration_minutesINTEGERTherapy usage duration in minutes
session_statusVARCHAR(20)Processing status of the usage session
Tablesusersmyair_usage_sessions
Your solutionPostgreSQL
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