Amazon’s DynamoDB is a fully managed database service running inside the AWS cloud which is super-scalable and fast. It is perfect for write-intensive workflows and low-latency queries. Its main advantages are the adjustable read and write performance and global secondary indexes (GSI).
We migrated from Cassandra to DynamoDB a while back. This decision was taken mainly because of the tunable performance and also because it’s a managed service and we had one less thing to maintain. Later we found out that global indexes could help us save a lot of extra costs and so we implemented a simple solution, which we call “shared tables”.