How it works...

PostgreSQL can dynamically load libraries in the following ways:

• Using the explicit LOAD command in a session
• Using the shared_preload_libraries parameter in postgresql.conf at the server start
• At the session start, using the local_preload_libraries parameter for a specific user, as set using ALTER ROLE

PostgreSQL functions and objects can reference code in these libraries, allowing extensions to be bound tightly to the running server process. The tight binding makes this method suitable for use even in very high-performance applications, and there's no significant difference between additionally supplied features and native features.