What database replication structure is used in your project: master-slave or master-master?

In projects, two main database replication structures are often used:

• Master-Slave: There is one primary server (master) that handles all write operations, and one or more slaves for reading. Slaves are synchronized with the master. This approach simplifies read scaling but centralizes write operations.

• Master-Master: Multiple servers can accept writes and synchronize with each other. This increases fault tolerance and availability but requires conflict resolution during concurrent changes.

The choice depends on the project requirements: if simplicity and predominantly reading are important — master-slave; if high availability and write scalability are needed — master-master.

Example: a small application might use master-slave, while a distributed system with high load might use master-master.