Chapter 50. Overview of PostgreSQL Internals

Table of Contents

50.1. The Path of a Query
50.2. How Connections are Established
50.3. The Parser Stage
50.3.1. Parser
50.3.2. Transformation Process
50.4. The PostgreSQL Rule System
50.5. Planner/Optimizer
50.5.1. Generating Possible Plans
50.6. 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.