OrientDB

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.

MongoDB is a general purpose, document-based, distributed database built for modern application developers and for the cloud era. No database is more productive to use. Ship and iterate 3–5x faster with our flexible document data model and a unified query interface for any use case. Whether it’s your first customer or 20 million users around the world, meet your performance SLAs in any environment. Easily ensure high availability, protect data integrity, and meet the security and compliance standards for your mission-critical workloads. An integrated suite of cloud database services that allow you to address a wide variety of use cases, from transactional to analytical, from search to data visualizations. Launch secure mobile apps with native, edge-to-cloud sync and automatic conflict resolution. Run MongoDB anywhere, from your laptop to your data center.