History of SQL

In June 1970, Edgar F. Codd published the paper "A Relational Model of Data for Large Shared Data Banks".

Based on Codd's model introduced in his paper, a group at IBM's San Jose research center developed the System R relational database management system.

Later on, two members of IBM named Donald D. Chamberlin and Raymond F. Boyce subsequently created the Structured English Query Language (SEQUEL) to manipulate and manage data stored in System R database.

Later the name SEQUEL was changed to SQL because SEQUEL was a trademark of the UK-based Hawker Siddeley aircraft company.

In 1979, Relational Software, Inc. (now Oracle Corporation) introduced the first commercially available implementation of SQL.

That was the Oracle version 2 and was available for VAX computer.

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