Redis Study Flashcards
High-speed in-memory key-value data structure store used as a database, cache, and message broker. Click any card to flip and test your knowledge.
What data structures does Redis support?
Strings, Hashes, Lists, Sets, Sorted Sets (ZSet), Bitmaps, HyperLogLogs, Geospatial indexes, and Streams.
What is TTL in Redis?
Time-To-Live (TTL) sets an automated expiration time after which Redis deletes the key from RAM.
How does Redis persistence work?
Redis supports RDB (point-in-time snapshot files) and AOF (Append-Only File logging every write command).
What is Pub/Sub in Redis?
A messaging pattern where publishers send messages to channels without knowing connected subscribers.
What is a Sorted Set (ZSET)?
A collection of unique strings where each element is associated with a floating-point score used for ordering.
What is Redis Sentinel?
A system providing high availability, monitoring, notification, and automatic failover for Redis primary nodes.
What is Redis Cluster?
Provides a way to run a Redis installation where data is automatically sharded across 16,384 hash slots.
What is Pipeline execution in Redis?
Sending multiple commands to the server without waiting for individual replies, reducing round-trip time (RTT).
What is the LRU Eviction Policy?
Least Recently Used (LRU) automatically evicts least recently accessed keys when RAM usage hits maxmemory limits.
How do Lua scripts execute in Redis?
Lua scripts run atomically on the Redis server, guaranteeing no other command executes concurrently during script run.
Need practical SQL queries for Redis?
Explore our ready-to-use copy-paste query recipes in the Cookbook.