Amazon DynamoDB is a managed key-value store that was one of the first NoSQL databases to be made available in the cloud. A NoSQL database is an alternative to the traditional relational databases that have been used for a variety of purposes in the industry for decades. DynamoDB does not offer many of the standard features of an RDBMS, such as table joins and ACID semantics. ACID stands for Atomic, Consistent, Isolated, and Durable. Consistency is one of the key trade-offs normally made with a NoSQL database since these systems are designed to run in a distributed fashion across a multitude of commodity machines. That being said, it is possible to make consistent reads with DynamoDB, and now you can even initiate transactions across operations, so the lines are being blurred somewhat.

There are still big differences with how you have to approach DynamoDB. It is a key-value store, and you do not use SQL to create, read, update, or delete records. You cannot write ad hoc queries across multiple tables, and in fact, tables are completely disconnected from one another. Each table has its own configuration, and in fact, if you find yourself creating multiple tables for a single service, you may not be following design best practices. Each DynamoDB table should have a single, simple job to perform, which aligns well with microservice design patterns and the overall DevOps philosophy.