System Design · Senior · Question 56 of 75

How would you implement a real-time game leaderboard?

✓Correct answer: With a sorted set (e.g. Redis ZSET) that keeps scores ordered and returns rank and top N in logarithmic time
2By sorting all players in SQL on every request
3By sorting in the browser

Explanation

Persist scores in a durable store; the sorted set acts as a fast, rebuildable index.

Further reading

Redis: Sorted sets ↗

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