An open source RDBMS that started as a research project at Berkeley in the 1970’s. There are now two strains of Ingres; the university Ingres (also known as Berkeley Ingres), which is open source, and also a commercial version called OpenIngres, which uses SQL and some forms of QUEL as its language for queries and database transactions. The university Ingres is believed to be the first implementation of a relational database management system that pre-dates IBM's System R. Version 8.9 was the last public release of University Ingres and it was discontinued in 1985. Ingres is also written as INGRES.
