SQL Definition

SQL, stands for structured query language, is a domain-specific declarative programming language based on tuple relational calculus and relational algebra. It is used in programming and designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS).

RDBMS is a relational database management system and stores related data in database objects called table which consists of rows (aka Records) and columns (aka Fields).  

RDSMS is a distributed, in-memory data stream management system that use SQL queries to process unstructured and structured data stream in real-time.

SQL History

SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd in the early 1970s.

SQL became a standard of the American National Standards Institute (ANSI) in 1986 and of the International Organization for Standardization (ISO) in 1987. Recent version was published in 2016.