
Datomic
MySQL
MarkLogic Server
Valentina Server
Google Cloud Datastore
Datahike
Matisse
Oracle TimesTen
4D
Redis
LiveCode Platform
MongoDB
CouchBase
Azure Cosmos DB
ESM Tools
OrientDB
DatomicMySQL - The world's most popular open source database
Redis - Redis is an open source in-memory data structure project implementing a distributed, in-memory key-value database with optional durability.
MarkLogic Server - MarkLogic Server is a multi-model database that has both NoSQL and trusted enterprise data management capabilities.
LiveCode Platform - It is Both Under the GPL and it is also Proprietary if using the GPL version the software you make...
Valentina Server - Valentina Server is 3 in 1: Valentina DB Server / SQLite Server / Report Server
MongoDB - MongoDB (from "humongous") is a scalable, high-performance NoSQL database.