PostgreSQL, a robust and open-source relational database system, is renowned for its native replication mechanisms, logical replication, and physical replication (also known as streaming replication). PostgreSQL 16 includes numerous improvements in logical replication designed to enhance performance, bolster data consistency, and advance compatibility.

In the context of PostgreSQL, logical replication employs a publisher/subscriber model to mirror changes between PostgreSQL servers. The primary node, where the database resides, is the publisher, while the stand-by node, which receives transaction copies, is the subscriber. Changes in the database are replicated from the publisher node to one or more subscriber node(s) identified by the subscription.