Book Image

MongoDB Cookbook - Second Edition - Second Edition

By : Amol Nayak
Book Image

MongoDB Cookbook - Second Edition - Second Edition

By: Amol Nayak

Overview of this book

MongoDB is a high-performance and feature-rich NoSQL database that forms the backbone of the systems that power many different organizations – it’s easy to see why it’s the most popular NoSQL database on the market. Packed with many features that have become essential for many different types of software professionals and incredibly easy to use, this cookbook contains many solutions to the everyday challenges of MongoDB, as well as guidance on effective techniques to extend your skills and capabilities. This book starts with how to initialize the server in three different modes with various configurations. You will then be introduced to programming language drivers in both Java and Python. A new feature in MongoDB 3 is that you can connect to a single node using Python, set to make MongoDB even more popular with anyone working with Python. You will then learn a range of further topics including advanced query operations, monitoring and backup using MMS, as well as some very useful administration recipes including SCRAM-SHA-1 Authentication. Beyond that, you will also find recipes on cloud deployment, including guidance on how to work with Docker containers alongside MongoDB, integrating the database with Hadoop, and tips for improving developer productivity. Created as both an accessible tutorial and an easy to use resource, on hand whenever you need to solve a problem, MongoDB Cookbook will help you handle everything from administration to automation with MongoDB more effectively than ever before.
Table of Contents (17 chapters)
MongoDB Cookbook Second Edition
Credits
About the Authors
About the Reviewers
www.PacktPub.com
Preface
Index

Manually padding a document


Without getting too much into the internals of the storage, MongoDB uses memory mapped files, which means that the data is stored in files exactly as how it would be in memory and it would use the low level OS services to map these pages to memory. The documents are stored in continuous locations in mongo data files and problem arises when the document grows and no longer fits in the space. In such scenarios, mongo rewrites the document towards the end of the collection with the updated data and clearing up the space where it was originally placed (note that this space is not released to OS as free space).

This is not a big problem for applications that don't expect the documents to grow in size. However, this is a big performance hit for those who foresee this growth in the document size over a period of time and potentially a lot of such document movements. With the release of MongoDB 3.0, the Power of 2 method became the default size allocation strategy. As...