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Data Structures · easy

1. In-Memory Data Structures

Strings, Hashes, Lists, Sets, and Sorted Sets (ZSET).

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Redis is an in-memory key-value data structure store: - Strings: Text, serialized blobs, atomic counters (`INCR`). - Hashes: Field-value maps ideal for objects (`HSET`, `HGETALL`). - Sorted Sets (ZSET): Elements ordered by score; powers rate limiters and leaderboards (`ZADD`, `ZRANGEBYSCORE`).

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Check your understanding

1. Which Redis data structure is optimal for implementing real-time leaderboards and sliding-window rate limiters?
Sorted Sets (ZSET)HashesListsBitmaps
2. Is Redis single-threaded for core command execution?
Yes, core command processing runs on a single event loop to eliminate race conditions without mutex locksNo, multi-threaded per keyOnly on WindowsNo, it uses thread pools for all commands

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