Firebird RDBMS offers ANSI SQL features & runs on Linux, Windows & several Unix platforms. Features excellent concurrency & performance & powerful stored procedure & trigger language.
More information and downloads at https://firebirdsql.org/, issue tracker is https://github.com/FirebirdSQL/firebird/issues
A relational database management system, based on the principles laid down in the book "Databases, Types, and The Relational Model: The Third Manifesto" by C. J. Date and Hugh Darwen.
Generic Object Oriented Database System
Distributed thick-client OODBMS using aspect-oriented approach to build transparent interface to database from OO programming languages (C++, Java, C#)
Object-oriented simulation-ready database simultaneously supports Java and C# APIs. Fully-transactional. Uses time-stamps and user ID to track all changes. Supports objects with properties whose values change in time under complex patterns.
Dynamic Work and Complex Project Management Platform | Quickbase
Quickbase is the leading application platform for dynamic work.
Our no-code platform lets you easily create, connect, and customize enterprise applications that fix visibility and workflow gaps without replacing a single system.
EyeDB is an Object Oriented Database Management System (OODBMS) providing an advanced object model (inheritance, collections, arrays, methods, triggers, constraints), an object definition language, an object query language and C++ and Java bindings.
DBIO is a tool to simulate Online Transaction Processing Database, which can be used to model production envirment for I/O test. A standard configuration file contained in the software simulates TPCC-Like I/O workload, which is modeled from DB2 Database running TPCC-Like workload. DBIO can also do data consistency check after the I/O workload test.
picoSQL is an Italian multi-user relational database management system with transactions support. Because it derives from a commercial project, it is already robust, fast, and rather complete.