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SQL Aggregation Across Tables
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SQL Aggregation Across Tables

MediumSQL · PostgreSQL

Problem

Write a SQL query to aggregate user data from multiple tables for Disney Experiences.

Return one row for each active user, combining reservation and park-entry activity. Include users without matching reservations or park-entry events, count only confirmed or completed reservations, and treat missing monetary values as zero.

Output

  1. Columns: user_id, user_name, reservation_count, total_spend, park_entry_count, and last_park_entry
  2. One row per active user
  3. Sort by total_spend descending, then user_id ascending

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User display name
statusVARCHAR(20)User account status
reservations
ColumnTypeDescription
reservation_idPKINTUnique reservation identifier
user_idINTUser who made the reservation
statusVARCHAR(20)Reservation lifecycle status
amountDECIMAL(10,2)Reservation amount
visit_events
ColumnTypeDescription
event_idPKINTUnique visit event identifier
user_idINTUser associated with the event
event_typeVARCHAR(30)Type of visit event
event_dateDATEDate of the event
Tablesusersreservationsvisit_events
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