AWS updated DynamoDB with the ability to publish near real-time notifications of data changes. This new capability – called DynamoDB Streams – spawned two additional features for the NoSQL database-as-a-service: DynamoDB Triggers fire based on specific data changes found in a DynamoDB Stream, and cross-region replication is driven by a DynamoDB Streams-based architecture.
Amazon DynamoDB, the NoSQL database service of AWS now supports online indexing. Along with this, customers can now buy reserved capacity for long term usage.
In their move to event driven architecture, Amazon introduced two enabling technologies allowing the conversion of DynamoDB and S3 written data into events, which can be consumed by other applications and used by Lambda architecture.
Last week, the Amazon Web Services team made changes to their DynamoDB NoSQL database service that improve JSON support, improve scalability, and expand the free usage tier. Developers can now use AWS SDKs to store, index, query, and update large JSON documents while consuming up to 25GB of free storage.
Developed since 2010 by Rich Hickey and the Relevance team, Datomic offers some new approaches to database architecture. Leveraging current trends in cloud and storage it has strong transactions, rich query API and read scaling.