SQL Funnel Path Query | Dataford Interview Questions

Your question is SQL Funnel Path Query. Start with the requirements and the two tables on the right.

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Problem

Uber's rider analytics team wants to understand how riders progress through the request funnel. Write a PostgreSQL query that identifies the most common observed path across five Uber ride steps during January 2025.

Requirements

Join rider records to funnel events and keep only January 2025 events from the five defined funnel steps.
Build one ordered path per rider using STRING_AGG, preserving repeated events and ordering ties by event_id.
Return each distinct path, the number of riders following it, and its percentage of all riders with at least one valid funnel event.
Sort by rider count descending, then path ascending.

Schema

riders

Column	Type	Description
rider_idPK	INTEGER	Unique rider identifier
rider_name	VARCHAR(100)	Rider display name
city	VARCHAR(80)	Rider's operating city

rider_funnel_events

Column	Type	Description
event_idPK	INTEGER	Unique funnel event identifier
rider_id	INTEGER	References riders.rider_id
event_name	VARCHAR(40)	Observed funnel step
event_time	TIMESTAMP	Timestamp when the event occurred