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System R - http://www.mcjones.org/System_R/
The first implementation corrupted from the relational model, was the basis for SQL and DB2. A site preserving early history of a technology that became a critical business tool. |
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http://leap.sourceforge.net/ - http://leap.sourceforge.net/
An incomplete relational algebra DBMS. [Free software, GNU GPL] |
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Starbase Data Tables - http://cfa-www.harvard.edu/~john/starbase/starbase.html
An ASCII quasi-relational database for POSIX. |
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FirstSQL - http://www.firstsql.com/
Java in-memory SQL92 DBMS with sane NULLs processing. Purports to actually strive to follow Codd's rules. |
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http://www.strozzi.it/cgi-bin/CSA/tw7/I/en_US/nosql/ - http://www.strozzi.it/cgi-bin/CSA/tw7/I/en_US/nosql/
Portable relational database management system without arbitrary limits that runs under POSIX operating systems. It uses the Operator-Stream Paradigm. |