Can you explain the principles of horizontal sharding and its use in data storage systems?

Horizontal sharding is a database scaling method where data is divided into parts (shards) by rows and distributed across different servers or nodes.

Unlike vertical sharding (where data is divided by columns), horizontal sharding splits a table into several parts, each containing a subset of rows.

Examples of usage:

• A user table is split by ID range: users with IDs 1-10000 on one server, 10001-20000 on another.
• Database queries are directed to the appropriate shard based on the key (e.g., user ID).

Advantages of horizontal sharding:

• Allows handling more data and queries by distributing the load.
• Reduces load on a single server.
• Ensures system scalability.

Disadvantages:

• Complexity in implementation and maintenance.
• Difficulties with queries that involve multiple shards.

Thus, horizontal sharding helps scale data storage systems by distributing data and load across multiple nodes.