4D - 4D is a relational database management system and IDE.
MySQL - The world's most popular open source database
H2 Database - H2 is free SQL database written in Java
PostgreSQL - PostgreSQL is a powerful, open source object-relational database system.
ESM Tools - ESM Tools is a powerful and widely known software development platform that comes with a centralized model infrastructure, providing the common frame for compiling, running, downloading, and organizing models (ones or multiple).
SQLite - SQLite Home Page