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You can choose your language settings from within the program. This article is about the database language. For the topic of the word, see sequel. SQL was one of the first commercial languages for Edgar F.
Codd’s relational model, as described in his influential 1970 paper, “A Relational Model of Data for Large Shared Data Banks”. SQL was initially developed at IBM by Donald D. Boyce after learning about the relational model from Ted Codd in the early 1970s. Chamberlin and Boyce’s first attempt of a relational database language was Square, but it was difficult to use due to subscript notation.
After moving to the San Jose Research Laboratory in 1973, they began work on SEQUEL. In the late 1970s, Relational Software, Inc. Codd, Chamberlin, and Boyce, and developed their own SQL-based RDBMS with aspirations of selling it to the U. DS, and DB2, which were commercially available in 1979, 1981, and 1983, respectively.
SQL deviates in several ways from its theoretical foundation, the relational model and its tuple calculus. Critics argue that SQL should be replaced with a language that strictly returns to the original foundation: for example, see The Third Manifesto. Clauses, which are constituent components of statements and queries. In some cases, these are optional. Boolean truth values and are used to limit the effects of statements and queries, or to change program flow. Queries, which retrieve the data based on specific criteria. This is an important element of SQL.