Amazon SimpleDB – the highly available, scalable, and flexible non-relational data store – now enables Consistent Reads and Conditional Puts & Deletes. Consistent Reads provide the ability to specify the consistency characteristic you require for each read call within your application, with an eventually consistent read optimized for lowest latency and highest throughput and a consistent read that provides “read my last write” capability. Conditional Puts & Deletes are mechanisms for inserting, updating, or deleting one or more attributes of an item with full transactional semantics using a single PutAttributes or Delete Attributes API call.
Previously, Amazon SimpleDB provided only eventually consistent reads. By offering a new Consistent Reads option and transactional semantics, AWS aims to facilitate development of additional classes of applications with Amazon SimpleDB. Visit the Amazon SimpleDB page to learn more.