Book Image

Web Development with Django Cookbook- Second Edition - Second Edition

By : Aidas Bendoraitis
Book Image

Web Development with Django Cookbook- Second Edition - Second Edition

By: Aidas Bendoraitis

Overview of this book

Django is a web framework that was designed to strike a balance between rapid web development and high performance. It has the capacity to handle applications with high levels of user traffic and interaction, and can integrate with massive databases on the backend, constantly collecting and processing data in real time. Through this book, you'll discover that collecting data from different sources and providing it to others in different formats isn't as difficult as you thought. It follows a task-based approach to guide you through all the web development processes using the Django framework. We’ll start by setting up the virtual environment for a Django project and configuring it. Then you’ll learn to write reusable pieces of code for your models and find out how to manage database schema changes using South migrations. After that, we’ll take you through working with forms and views to enter and list data. With practical examples on using templates and JavaScript together, you will discover how to create the best user experience. In the final chapters, you'll be introduced to some programming and debugging tricks and finally, you will be shown how to test and deploy the project to a remote dedicated server. By the end of this book, you will have a good understanding of the new features added to Django 1.8 and be an expert at web development processes.
Table of Contents (18 chapters)
Web Development with Django Cookbook Second Edition
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Introduction


Whether you build your own forum, threaded comments, or categorization system, there will be a moment when you need to save hierarchical structures in the database. Although the tables of relational databases (such as MySQL and PostgreSQL) are of a flat manner, there is a fast and effective way to store hierarchical structures. It is called Modified Preorder Tree Traversal (MPTT). MPTT allows you to read the tree structures without recursive calls to the database.

At first, let's get familiar with the terminology of the tree structures. A tree data structure is a recursive collection of nodes, starting at the root node and having references to child nodes. There is a restriction that no node references back to create a loop and no reference is duplicated. The following are some other terms to learn:

  • Parent is any node that is referencing to the child nodes.

  • Descendants are the nodes that can be reached by recursively traversing from a parent to its children. Therefore, the node...