LokiJS

The super fast in-memory javascript document oriented database. Enable offline-syncing to your SQL/NoSQL database servers with SyncProxy !! Code-free real time syncing, ideal for mobile, electron and web apps. https://github.com/techfort/LokiJS

mindsdb

Machine Learning in your database Integrate MindsDB and make predictions on top of the data in your existing database using SQL queries, eliminating costly replication and simplifying your application infrastructure. https://mindsdb.com

EdgeDB

The next generation database EdgeDB combines the simplicity of a NoSQL database with relational model’s powerful querying, strictness, consistency, and performance. https://www.edgedb.com