Firebird

Firebird is a relational database offering many ANSI SQL standard features that runs on Linux, Windows, and a variety of Unix platforms. Firebird offers excellent concurrency, high performance, and powerful language support for stored procedures and triggers. It has been used in production systems, under a variety of names, since 1981.
FREE LIKE A BIRD. Anyone can build a custom version of Firebird, as long as the modifications are made available, under the same IDPL licensing, for others to use and build on.
FREE LIKE FREE BEER. No fees for download, registration, licensing or deployment, even you distribute Firebird as part of your commercial software package.
The Firebird Project is a commercially independent project of C and C++ programmers, technical advisors and supporters developing and enhancing a multi-platform relational database management system based on the source code released by Inprise Corp (now known as Borland Software Corp) on 25 July, 2000.
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