Introduction

1. PostgreSQL is an Object Relational Database Management System.

2. It's also called ORDMS.

3. It's an Open-Source Database Management System.

4. It uses MYSQL standards.

5. It follows a client-server architecture.

Client Applications: PostgreSQL can be accessed by various client applications such as command-line tools, graphical user interfaces (GUIs), web applications, and programming languages.

Server: The PostgreSQL server is the core component that manages the database and handles client requests. It consists of several processes and components:
Postmaster: This is the main process that manages the database connections, authentication, and other server-level operations.

• Background Writer (BGW): It manages the writing of modified data from memory (shared buffers) to disk (data files) to ensure data durability.

• Checkpointer: This process writes dirty pages from shared buffers to disk and updates the checkpoint records.

• Autovacuum Launcher: It automatically initiates the vacuuming and analyzing of tables to reclaim disk space and update query statistics.

• Shared Memory: PostgreSQL uses shared memory to facilitate communication and data sharing among various server processes.