Can you explain what is meant by sharding in non-relational databases?

Sharding in NoSQL databases is a method of horizontal partitioning of data into parts (shards) that are stored on different servers or nodes. Each part contains a subset of the entire database, which allows distributing the load and increasing scalability.

For example, if you have a collection of users, you can split them by the first letter of their last name or by geographic region, and each shard will store data only for its part. This speeds up queries and increases fault tolerance, as the load is distributed among multiple machines.

Main advantages of sharding:

• Scalability: new shards can be added to increase data volume.
• Improved performance through parallel processing.
• Reduced risk of data loss in case of a node failure.

However, sharding complicates the architecture and requires a thoughtful approach to choosing the sharding key.