- Developed by IBM as SEQUEL in 1970s
- Oracle coperation took the ownership of SQL after 1977
- ANSI standardized SQL in 1986 – SQL1
- SQL2 introduced in 1992
- SQL3 was produced in 1999
Database Sublanguage…
- SQL2 standard can be divided in to four major parts;
DDL – commands concerned with declaring the structure of schemas and tables.
DML – commands concerned with retrieving data and updating data in tables.
DIL – data integrity is attached to the DD. Commands concerned with declaring entity, referential and domain integrity.
DCL – commands concerned with administering the database.
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