Sharding pattern means divide the data store into horizontal partitions or shards. Each shard has the same schema, but holds its own distinct subset of the data.
A shard is a data store in its own right (it can contain the data for many entities of different types), running on a server acting as a storage node.
This pattern offers the following benefits:
- You can scale the system out by adding further shards running on additional storage nodes.
- A system can use off the shelf commodity hardware rather than specialized (and expensive) computers for each storage node.
- You can reduce contention and improved performance by balancing the workload across shards.
- In the cloud, shards can be located physically close to the users that will access the data.