Book Image

Moodle 1.9 Extension Development

Book Image

Moodle 1.9 Extension Development

Overview of this book

Moodle gives you the power to create and customize feature-rich plug-ins. If you can write Moodle plug-ins, you can make it do just about anything. From making the site easier to administer, to new features, to completely changing the way it looks; plug-ins are the method Moodle offers to customize and extend its functionality. This book will show you how to build all sorts of Moodle plug-ins: admin plug-ins, Blocks, Activities, Grading components, Reports, Fliters that change the way your site works and looks. You will develop standard Moodle plug-ins such as Activities, Filters, and Blocks by creating functioning code that you can execute in your own Moodle installation. Writing modular plug-ins for Moodle will be a large focus of this book.This book will take you inside Moodle and provide you with the ability to develop code the “Moodle way”.This book will expose you to all of the core code functions in Moodle, in a progressive, understandable way. You will learn what libraries are available, what the API calls are, how it is structured and how it can be expanded beyond the plug-in system.You will begin by getting an understanding of the basic architecture that Moodle uses to operate in. Next you will build your first plug-in; a block. You will carry on building other Moodle plug-ins, gaining knowledge of the “Moodle way” of coding, before plunging deeper into the API and inner libraries. Lastly, you will learn how to integrate Moodle with other systems using a variety of methods.When you have completed, you will have a solid understanding of Moodle programming and knowledge of how to extend its functionality in whatever way you want.
Table of Contents (19 chapters)
Moodle 1.9 Extension Development
Credits
About the Authors
About the Reviewer
Preface

Chapter 6. Developer's Guide to the Database

Moodle supports a variety of SQL databases to store program information. To do that, Moodle provides powerful code libraries to let you write database-agnostic code. Moodle also enforces strict database layout design, allowing you to understand table structures easily. We will examine Moodle's database structures, policies, and libraries in order to better understand how to build our code.

This chapter covers the following topics:

  • Overall structure of the Moodle database

  • Coding methods and APIs for accessing databases

  • Tools and programming tricks to help with your development projects

The database structure

Every data table in Moodle has one common element: the first field is an integer field called id. This field is a unique field that serves as the Primary Key for every table. It also serves as the Foreign Key to any other data table that contains a reference to that table.

Although this may seem excessive to some database programmers, as there are...