PostgreSQL: Documentation: 14: Chapter 53. Frontend/Backend Protocol

May 8, 2025: PostgreSQL 17.5, 16.9, 15.13, 14.18, and 13.21 Released! | PostgreSQL 18 Beta 1 Released!

Documentation → PostgreSQL 14

Supported Versions: Current (17) / 16 / 15 / 14 / 13

Development Versions: 18 / devel

Unsupported versions: 12 / 11 / 10 / 9.6 / 9.5 / 9.4 / 9.3 / 9.2 / 9.1 / 9.0 / 8.4 / 8.3 / 8.2 / 8.1 / 8.0 / 7.4 / 7.3 / 7.2 / 7.1

Chapter 53. Frontend/Backend Protocol
Prev	Up	Part VII. Internals	Home	Next

Chapter 53. Frontend/Backend Protocol

Table of Contents

53.1. Overview

53.1.1. Messaging Overview
53.1.2. Extended Query Overview
53.1.3. Formats and Format Codes

53.2. Message Flow

53.2.1. Start-up
53.2.2. Simple Query
53.2.3. Extended Query
53.2.4. Pipelining
53.2.5. Function Call
53.2.6. COPY Operations
53.2.7. Asynchronous Operations
53.2.8. Canceling Requests in Progress
53.2.9. Termination
53.2.10. SSL Session Encryption
53.2.11. GSSAPI Session Encryption

53.3. SASL Authentication

53.3.1. SCRAM-SHA-256 Authentication

53.4. Streaming Replication Protocol

53.5. Logical Streaming Replication Protocol

53.5.1. Logical Streaming Replication Parameters
53.5.2. Logical Replication Protocol Messages
53.5.3. Logical Replication Protocol Message Flow

53.6. Message Data Types

53.7. Message Formats

53.8. Error and Notice Message Fields