Contents

• Postgres Function Extension Template
  • Getting started
  • Building
    • Build steps
    • Installation
  • Using the extension
  • Running the tests
  • Distributing your extension
  • Files

Postgres Function Extension Template

This repository contains a template for creating a Postgres function. The goal of this template is to provide a starting point for the creation of functions for Postgres.

This extension template implements the Soundex Algorithm as a function.

Getting started

First step to getting started is to create your own repo from this template by clicking Use this template. Then clone your new repository using

git clone https://github.com/<you>/<your-new-extension-repo>.git

Building

Build steps

To build the extension, run:

make

The binary that will be built and the other components of the extension are:

./soundex-function--1.0.0.sql
./soundex-function.control
./soundex-function.so

• soundex-function--1.0.0.sql is the SQL definition that creates the function.
• soundex-function.control is the control file that describes the extension to Postgres.
• soundex-function.so is the shared object that is created that is the heart of the extension.

Installation

To install the extension, run:

make install

Using the extension

To use the extension:

CREATE EXTENSION "soundex-function";

We can then run the function that the extension created:

SELECT soundex('postgres');
 soundex
---------
 P232
(1 row)

Running the tests

Tests can be executed after the extension is installed:

make installcheck

The tests that are run are stored in the ./sql directory, and specified in the Makefile.

Distributing your extension

There are multiple ways to distribute your extension, and this template contains the metadata files for PGXMAN and PGXN.

• META.json - the metadata file for PGXN.
• extension.yaml - the build-kit file for PGXMAN.

Files

• Makefile is the build system file that sets up the build using the Postgres build system.
• soundex-function--1.0.0.sql is the SQL definition that creates the function.
• soundex-function.control is the control file that describes the extension to Postgres.
• src/function.c is the main function definition in C.
• src/soundex.c is the Soundex implementation in C.
• src/soundex.h is the header file for soundex.c.
• sql/soundex_function.sql is the file to be executed for tests.
• expected/soundex_function.sql is the file that the results of the tests are compared to.