Database Shrading
Database sharding is a type of database partitioning that separates very large databases into smaller, faster, more easily managed parts called data shards. The word shard means a small part of a whole.
Sharding is a method of splitting and storing a single logical dataset in multiple databases. By distributing the data among multiple machines, a shard can improve performance in retrieving the data.
Here are some key points about sharding:
-
Horizontal Partitioning: Sharding is a type of horizontal partitioning. While vertical partitioning involves creating tables with fewer columns and using additional tables to store the remaining columns, horizontal partitioning is about creating tables with fewer rows.
-
Data Distribution: In sharding, data is distributed across multiple databases such that each database only manages a subset of the data.
-
Scalability: Sharding can be a great way to achieve scalability. It can allow you to add additional machines to support more transactions and store more data.
-
Performance: Sharding can improve application performance through query load balancing and reducing the database index size.
-
Complexity: Implementing sharding architecture can be complex. Data distribution, shard performance, handling shard failures, and maintaining data consistency are some of the challenges with sharding.
-
Shard Key: The shard key is a data item that is used to determine the allocation of the rows to the shards. The choice of the shard key can impact the performance of the sharded database.
Sharding is used in data-intensive applications like social networks, IoT applications, and in high-traffic website backends. It's important to note that sharding comes with its own complexities and potential drawbacks, so it should be implemented judiciously.