Task

Facebook wants to measure habit strength by finding each user's longest streak of consecutive daily activity. Write a SQL query to return the longest daily activity streak per user.

Requirements

1. Treat multiple events by the same user on the same calendar date as a single active day.
2. A streak is a sequence of activity dates where each date is exactly 1 day after the previous active date.
3. Return one row per user with their user_id, longest streak length, streak start date, and streak end date.
4. If a user has multiple streaks with the same maximum length, return the earliest streak.
5. Order the final output by user_id ascending.

Table Definitions

facebook_activity

Sample Data

Expected Output