Book Image

MongoDB Fundamentals

By : Amit Phaltankar, Juned Ahsan, Michael Harrison, Liviu Nedov
Book Image

MongoDB Fundamentals

By: Amit Phaltankar, Juned Ahsan, Michael Harrison, Liviu Nedov

Overview of this book

MongoDB is one of the most popular database technologies for handling large collections of data. This book will help MongoDB beginners develop the knowledge and skills to create databases and process data efficiently. Unlike other MongoDB books, MongoDB Fundamentals dives into cloud computing from the very start – showing you how to get started with Atlas in the first chapter. You will discover how to modify existing data, add new data into a database, and handle complex queries by creating aggregation pipelines. As you progress, you'll learn about the MongoDB replication architecture and configure a simple cluster. You will also get to grips with user authentication, as well as techniques for backing up and restoring data. Finally, you'll perform data visualization using MongoDB Charts. You will work on realistic projects that are presented as bitesize exercises and activities, allowing you to challenge yourself in an enjoyable and attainable way. Many of these mini-projects are based around a movie database case study, while the last chapter acts as a final project where you will use MongoDB to solve a real-world problem based on a bike-sharing app. By the end of this book, you'll have the skills and confidence to process large volumes of data and tackle your own projects using MongoDB.
Table of Contents (15 chapters)
Preface

Properties of Indexes

In this section, we will cover different properties of indexes in MongoDB. An index property can influence the usage of an index and can also enforce some behavior on the collection. Index properties are passed as an option to the createdIndex function. We will be looking at unique indexes, TTL (time to live) indexes, sparse indexes, and finally, partial indexes.

Unique Indexes

A unique index property restricts the duplication of the index key. This is useful if you want to maintain the uniqueness of a field in a collection. The unique fields are useful for avoiding any ambiguity in identifying documents precisely. For example, in a license collection, a unique field such as license_number can help identify each document individually. This property enforces the behavior on the collection to reject duplicate entries. Unique indexes can be created on a single field or on a combination of fields. The following is the syntax to create a unique index on a single...