eXist-db

RavenDB is the pioneer NoSQL Document Database that is fully transactional (ACID) across your database and throughout your cluster. At a fraction of the total cost of ownership (TCO), our open source distributed database offers high availability and high performance with zero administration. It is designed as an easy to use all-in-one database which minimizes the need for third party addons, tools, or support to boost developer productivity and get your project into production fast. You can setup and secure a data cluster in minutes and deploy in the cloud, on-premise or in a hybrid environment. RavenDB offers a Database as a Service solution, allowing you to pass on all your database operations to us so you can focus exclusively on your application. RavenDB has a built-in storage engine, Voron, that operates at speeds up to 1 million reads per second and 150,000 writes per second on a single node using simple commodity hardware to increase your application’s performance.

Berkeley DB is a family of embedded key-value database libraries providing scalable high-performance data management services to applications. The Berkeley DB products use simple function-call APIs for data access and management. Berkeley DB enables the development of custom data management solutions, without the overhead traditionally associated with such custom projects. Berkeley DB provides a collection of well-proven building-block technologies that can be configured to address any application need from the hand-held device to the data center, from a local storage solution to a world-wide distributed one, from kilobytes to petabytes.