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7-Day Rolling User Average in SQL
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7-Day Rolling User Average in SQL

MediumSQL · PostgreSQL

Problem

Given a dataset with a timestamp column and user events, write a SQL query to compute a 7-day rolling average of events per user using window functions.

Use the provided user, event, and calendar-date tables. Treat dates without events as zero-event days.

Output

  1. One row per user and calendar date.
  2. Columns: user_id, event_date, daily_event_count, and rolling_7_day_avg.
  3. Include all users and calendar dates, sort by user_id, then event_date.

Schema

users
ColumnTypeDescription
user_idPKINTUnique user identifier
user_nameVARCHAR(100)User display name
user_events
ColumnTypeDescription
event_idPKINTUnique event identifier
user_idINTUser who generated the event
event_timestampTIMESTAMPTimestamp when the event occurred
event_typeVARCHAR(50)Type of user event
calendar_dates
ColumnTypeDescription
calendar_datePKDATECalendar date included in the reporting range
Tablesusersuser_eventscalendar_dates
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