In the early 1970s, Chamberlin and Boyce learned about the relational model from Ted Codd. They called this version SEQUEL (Structured English Query Language), but later cut the acronym short to SQL ascribing to trademark issues. The language is made of elements as clauses, expressions, predicates, queries, statements, and insignificant whitespace. SQL, as we know it, is a domain-specific language for managing data in an RDBMS or for stream processing in an RDSMS.

SQL is a 4th-generation language and holds statements of the types DQL, DDL, DCL, and DML.