sql

sql (structured query language) is a comprehensive database language: it has statements for data definitions, queries, and updates. hence, it is both a ddl and a dml. in addition, it has facilities for defining views on the database, for specifying security and authorization, for defining integrity constraints, and for specifying transaction controls.
sql uses the terms table, row, and column for the formal relational model terms relation, tuple, and attribute, respectively.
[cite:@elmasri_db_2015 chapter 6 basic sql]

sql is primarily based on concepts from relational calculus and has been extended to incorporate some concepts from relational algebra aswell.
[cite:@elmasri_db_2015 chapter 8 the relational algebra and relational calculus]