neo4j - Meet Neo4j: The graph database platform powering today's mission-critical enterprise applications, including artificial intelligence, fraud detection and recommendations.
ForerunnerDB - ForerunnerDB is the only JavaScript database with a simple, rich JSON-based query language.
ArangoDB - A distributed open-source database with a flexible data model for documents, graphs, and key-values.
Alasql - Alasql.js - is a lightweight client-side in-memory SQL database designed to work in browser and...
Cayley - Open-source graph database.
PouchDB - Open-source JavaScript database inspired by Apache CouchDB that's designed to run well within the browser