Book Image

PostgreSQL 11 Server Side Programming Quick Start Guide

By : Luca Ferrari
Book Image

PostgreSQL 11 Server Side Programming Quick Start Guide

By: Luca Ferrari

Overview of this book

PostgreSQL is a rock-solid, scalable, and safe enterprise-level relational database. With a broad range of features and stability, it is ever increasing in popularity.This book shows you how to take advantage of PostgreSQL 11 features for server-side programming. Server-side programming enables strong data encapsulation and coherence. The book begins with the importance of server-side programming and explains the risks of leaving all the checks outside the database. To build your capabilities further, you will learn how to write stored procedures, both functions and the new PostgreSQL 11 procedures, and create triggers to perform encapsulation and maintain data consistency. You will also learn how to produce extensions, the easiest way to package your programs for easy and solid deployment on different PostgreSQL installations.
Table of Contents (12 chapters)

Executing dynamic statements

Non-PL/pgSQL statements are sent to the server engine as regular SQL statements. A few examples in the previous sections have already performed some queries within code blocks. It is possible for a code block to construct an SQL statement dynamically to be executed by the server engine. This can be achieved using the EXECUTE statement.

An EXECUTE statement is made of three parts:

  • A mandatory query string, which represents the SQL statement that will be executed
  • An optional INTO (or INTO STRICT) clause, which allows us to store values from the previous statement in variables
  • An optional USING clause, which provides positional values for parameter substitution

The query string will not be interpolated, which means that no variable substitution will be performed on it. In order to insert variable values into a query string, we must use special positional...