#0123

Latest Row Per User With ROW_NUMBER

MediumSQL25 min20 XP

Problem

Given events(user_id, event_date, status), return the latest row per user sorted by user_id.

Latest-row extraction is a staple SQL task for profiles, labels, and slowly changing data.

events(user_id INTEGER, event_date TEXT, status TEXT)

Example 1

Inputmultiple status rows per user

Outputlatest status per user

ROW_NUMBER ranks rows inside each user partition by newest date.

CodeSQL

WITH ranked AS (
  -- write your code here
)
SELECT user_id, event_date, status
FROM ranked;

WITH ranked AS (
  -- write your code here
)
SELECT user_id, event_date, status
FROM ranked;

Visible browser tests run here when available.

Testcases1 visible / 3 hidden categories

Core example

Inputmultiple status rows per user

Expectedlatest status per user

ROW_NUMBER ranks rows inside each user partition by newest date.

Hidden Test Categories

single event userunordered inputtie-break discussion