Adam Marcus Unlike most of the other projects in this book, NoSQL is not a tool, but an ecosystem composed of several complimentary and competing tools. The tools branded with the NoSQL monicker provide an alternative to SQL-based relational database systems for storing data. To understand NoSQL, we have to understand the space of available tools, and see how the design of each one explores the space of data storage possibilities. If you are considering using a NoSQL storage system, you should first understand the wide space of options that NoSQL systems span. NoSQL systems do away with many of the traditional comforts of relational database systems, and operations which were typically encapsulated behind the system boundary of a database are now left to application designers. This requires you to take on the hat of a systems architect, which requires a more in-depth und...