Database replication and clustering are increasingly widespread solutions to scalability and high avail-ability challenges in current information systems. We offer a complete overview of these techniques, from theory to practice. We starts by making an overview of the main challenges involved and the algorithms and engineering techniques to address them. Then, provide an in depth description of the architecture of a modern open-source database replication system and a hands-on guide to its deployment. Therefore, the aim is both at database management system and middleware developers, as well as those making use of database technology in planning and deploying large scale applications.

The following are different replication techniques for SQL Database Servers.

Merge Replication
Lazy Replication
Eager Replication