MySQL Community Edition - MySQL :: MySQL Community Edition
Valentina Server - Valentina Server is 3 in 1: Valentina DB Server / SQLite Server / Report Server
MariaDB - An enhanced, drop-in replacement for MySQL
Datomic - The fully transactional, cloud-ready, distributed database
Mimer SQL - Mimer SQL is an SQL-based relational database management system from the Swedish company Mimer...
MarkLogic Server - MarkLogic Server is a multi-model database that has both NoSQL and trusted enterprise data management capabilities.