Database Sharding — PlanetScale

Sharding is the process of improving database scalability by distributing data across multiple servers, known as shards. This technique is widely used by large companies like Uber and Slack. Effective sharding involves choosing the right sharding strategy and shard key to optimize performance and avoid issues like cross-shard queries. PlanetScale, built on Vitess, provides tools to simplify sharding implementation and management. Additionally, sharding can help with data durability, high availability, and faster backups by using replicas.