<ul><li>Sharding is a technique where a database is split into smaller, manageable pieces to improve performance and scalability.</li><li>Sharding is necessary when the database outgrows the capacity of a single machine, query performance degrades, high availability is required, scaling up is not feasible, or for faster local access.</li><li>The main types of sharding include Key-Based (Hash) Sharding, Geo Sharding, Directory-Based (Lookup) Sharding, Range-Based Sharding, and Vertical Sharding.</li><li>Challenges of sharding include managing complexity, difficulty in rebalancing, expensive joins across shards, ensuring data consistency, and separate backup and recovery strategies for each shard.</li></ul>

Database Sharding: Breaking It Down Without Breaking Your DB

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