19  SQL history

• SQL is developed at IBM in the 1970s by Donald D. Chamberlin and Raymond F. Boyce.

• SQL is based on the article of Edgar F. Codd “A Relational Model of Data for Large Shared Data Banks” Codd (1970)

• Entity-relationship model introduced by Chen.

• First commercial version was released by Oracle in 1979.

• Although it is defined as declarative, it also has procedural elements.

Codd, E. F. 1970. “A Relational Model of Data for Large Shared Data Banks.” Communications of the ACM 13 (6): 377–87. https://doi.org/10.1145/362384.362685.