

Streak Leaderboard
You work for a popular language learning company and have a table containing ~900,000 lesson completions, including the date, user, and lesson ID.
Your task is to calculate the active streak for each user, then create a leaderboard of the top 10 users with the longest active streaks.
The streak length is the number of consecutive days with at least one lesson completion
For the purpose of this drill, consider the current date to be 2025-09-29
For a streak to be considered “active”, the user must have completed a lesson on 2025-09-28
See example below:

Submit your solution
How long is the third longest active streak?
