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Interactive practice · 10 questions on scaling, caching, databases, CDNs, sharding, replication, and the CAP theorem — easy to hard, with step-by-step explanations.
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Easy What component distributes incoming requests across multiple servers?
Answer: B — Load balancer
Easy What is the main purpose of a cache?
Answer: A — Store frequently used data for faster access
Medium In the CAP theorem, CAP stands for:
Answer: B — Consistency, Availability, Partition tolerance
Medium During a network partition, CAP says a distributed system must sacrifice one of:
Answer: B — Consistency or Availability
Medium Horizontal scaling means:
Answer: B — Adding more machines/nodes
Medium Which database type best fits flexible, schema-less document data?
Answer: A — Document store (NoSQL)
Medium What does a CDN primarily do?
Answer: A — Serve static content from edge locations near users
Hard Which technique splits one large database into smaller pieces across servers by a key?
Answer: C — Sharding
Hard Which are benefits of database replication? Select all that apply.
Answer: A, C
Hard Placing a message queue between two services mainly provides:
Answer: D — Asynchronous decoupling and buffering of work