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Running Total and User Ranking
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Running Total and User Ranking

MediumSQL · PostgreSQL

Problem

Write a SQL query using window functions to calculate a running total of daily revenue by user and rank users within each day.

Use the users and revenue_events tables. Include only completed events with non-null amounts. Ties in daily revenue share the same rank.

Output

  1. One row per user and event date, with user_id, user_name, event_date, daily_revenue, running_total, and daily_rank.
  2. Order by event_date, daily_rank, and user_id.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User display name
revenue_events
ColumnTypeDescription
event_idPKINTUnique revenue event identifier
user_idINTUser associated with the event
event_dateDATECalendar date of the event
amountNUMERIC(12,2)Revenue amount for the event
statusVARCHAR(20)Processing status of the event
Tablesusersrevenue_events
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