Chapter 51. Overview of PostgreSQL Internals

Table of Contents

51.1. The Path of a Query
51.2. How Connections Are Established
51.3. The Parser Stage
51.3.1. Parser
51.3.2. Transformation Process
51.4. The PostgreSQL Rule System
51.5. Planner/Optimizer
51.5.1. Generating Possible Plans
51.6. Executor


This chapter originated as part of [sim98], Stefan Simkovics' Master's Thesis prepared at Vienna University of Technology under the direction of O.Univ.Prof.Dr. Georg Gottlob and Univ.Ass. Mag. Katrin Seyr.

This chapter gives an overview of the internal structure of the backend of PostgreSQL. After having read the following sections you should have an idea of how a query is processed. This chapter does not aim to provide a detailed description of the internal operation of PostgreSQL, as such a document would be very extensive. Rather, this chapter is intended to help the reader understand the general sequence of operations that occur within the backend from the point at which a query is received, to the point at which the results are returned to the client.