Interview Q&A / System Design

1. Should you add read replicas or shard when the database is slow?

   Add read replicas when reads dominate, since they scale reads cheaply. Shard when writes or data size exceed one machine. Check indexes, queries and caching before either.

   BeginnerQuick answer1 min read
2. What is the difference between sharding and partitioning?

   Partitioning splits a big table into smaller parts, often inside one database. Sharding is partitioning where the parts live on different servers, so both data and load are spread across machines.

   BeginnerQuick answer1 min read