What is database replication?

Database replication is the process of copying and maintaining data from one database (the master) to one or more others (replicas). The goal is to increase system availability, fault tolerance, and scalability.

Main types of replication:

• Synchronous: changes are written simultaneously to the master and replicas, ensuring consistency but potentially reducing performance.
• Asynchronous: changes are first applied to the master, and then replicas are updated with a delay, which increases performance but may lead to data inconsistency.

In the context of Golang, replication can be used to build distributed systems where one service handles writing, and others handle reading, reducing load and increasing fault tolerance.

Example: the master database accepts write requests, while replicas handle read requests, allowing load scaling and data backup.