WHAT IS SQL?

 WHAT IS SQL?


    It is a domain-specific language used to manage data, especially in a relational database management system. It is particularly useful in handling structured data, i.e., data incorporating relations among entities and variables.


    Originally based upon relational algebra and tuple relational calculus, SQL consists of many types of statements, which may be informally classed as sublanguages, commonly: Data query Language (DQL), Data Definition Language (DDL), Data Control Language (DCL), and Data Manipulation Language (DML).


 

     SQL was one of the first commercial languages to use Edgar F. Codd's relational model. The model was described in his influential 1970 paper, "A Relational Model of Data for Large Shared Data Banks".[8] Despite not entirely adhering to the relational model as described by Codd, SQL became the most widely used database language.



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