35. GNU SQL Server

http://panda.ispras.ru/~gsql/
Portable multiuser relational database management system. It supports the full SQL89 dialect and has some extensions from SQL92. It provides multiuser access and transaction isolation based on predicative locks. The working OS is Unix; the working language is C. The program also uses RPC, shared memory, and message queues. Note: as of June 26, 2001, this program is no longer being maintained or developed.