Top Users by Engagement | Dataford Interview Questions

Your question is Top Users by Engagement. Start with the requirements and the two tables on the right.

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Problem

Dayforce wants to identify the most engaged users of its platform. Using activity recorded during Q2 2025, write a PostgreSQL query that ranks every user and returns the top 10% based on a defined engagement score.

Requirements

Include every user, including users with no qualifying activity during Q2 2025.
Calculate quarterly sessions and completed tasks from engagement_events.
Define engagement_score as (sessions * 2) + completed_tasks.
Use a window function to divide users into ten engagement deciles and return only decile 1, ordered by score descending.

Schema

users

Column	Type	Description
user_idPK	INT	Unique Dayforce user identifier
full_name	VARCHAR(100)	User's display name

engagement_events

Column	Type	Description
event_idPK	INT	Unique engagement event identifier
user_id	INT	User associated with the event
event_type	VARCHAR(30)	Type of engagement activity
engagement_value	INT	Number of represented sessions or completed tasks
occurred_on	DATE	Date on which the activity occurred