Book Image

Full Stack Web Development with Raspberry Pi 3

By : Soham Kamani
Book Image

Full Stack Web Development with Raspberry Pi 3

By: Soham Kamani

Overview of this book

Modern web technology and portable computing together have enabled huge advances in the Internet of Things (IoT) space,as well as in areas such as machine learning and big data. The Raspberry Pi is a very popular portable computer for running full stack web applications. This book will empower you to master this rapidly evolving technology to develop complex web applications and interfaces. This book starts by familiarizing you with the various components that make up the web development stack and that will integrate into your Raspberry Pi-powered web applications. It also introduces the Raspberry Pi computer and teach you how to get up and running with a brand new one. Next, this book introduces you to the different kinds of sensor you’ll use to make your applications; using these skills, you will be able to create full stack web applications and make them available to users via a web interface. Later, this book will also teach you how to build interactive web applications using JavaScript and HTML5 for the visual representation of sensor data. Finally, this book will teach you how to use a SQLite database to store and retrieve sensor data from multiple Raspberry Pi computers. By the end of this book you will be able to create complex full stack web applications on the Raspberry Pi 3 and will have improved your application’s performance and usability.
Table of Contents (13 chapters)
2
Getting Up-and-Running with Web Development on the Raspberry Pi

Aggregations

The power of SQL and SQLite does not end just in simple CRUD operations. SQLite exposes a number of useful functions that can be utilized to obtain even more meaningful insights from your data.

Some of the functions that we will be using to enhance our application are as follows:

  • avg(X): Returns the average of all values passed to it
  • max(X): Returns the maximum value out of the values passed to it
  • min(X): Returns the minimum value out of the values passed to it
  • count(X): Returns the total number of values passed to it

Here, X denotes the column name to be aggregated.

Most of the functions provided by SQLite work on both text as well as numeric input. For example, max and min would also work on text input by ordering the provided values alphabetically. However, some functions (such as avg) may not make sense for text inputs, and although they return a result, they...