SQL and Data Modeling | Dataford Interview Questions

Your question is SQL and Data Modeling. Start with the requirements and the three tables on the right.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem

Describe your experience with SQL and data modeling in a professional setting.

Use the supplied relational schema to demonstrate that experience by producing a concise activity summary for active entities. Include entities without qualifying activity and classify them based on their total completed value.

Output

One row per active entity, including entities without qualifying events.
Return entity_name, group_name, completed_event_count, total_completed_value, latest_completed_date, and value_band.
Include only completed events from 2025-01-01 through 2025-03-31. Order by total_completed_value descending, then entity_id ascending.

Schema

data_entities

Column	Type	Description
entity_idPK	INT	Unique entity identifier
entity_name	VARCHAR(100)	Display name of the entity
entity_type	VARCHAR(50)	Classification of the entity
is_active	BOOLEAN	Whether the entity is active

data_events

Column	Type	Description
event_idPK	INT	Unique event identifier
entity_id	INT	Related entity identifier
event_date	DATE	Date on which the event occurred
status	VARCHAR(30)	Current event status
event_value	NUMERIC(12,2)	Numeric value associated with the event

entity_groups

Column	Type	Description
group_idPK	INT	Unique group identifier
entity_id	INT	Entity assigned to the group
group_name	VARCHAR(100)	Assigned group name