What is SQL?
Structured Query Language (SQL) is both the internatioal organization for standardization (ISO) and the American National Standards Institute (ANSI) standard language for creating, updating and querying relational database management systems (RDBMS). Both ISO and ANSI are influential in establishing standards for technology and computing. The standardization of SQL, at both the international and national levels, ensures compatibility and consistency in database development around the world.
SQL dates back to the 1970s when IBM, with the assistance of others, developed SEQUEL, structured english query lagnguage. SEQUEL involved a relational model, for large shared data banks, with multiple tables and multiple users. A revised version was named SEQUEL/2, and later, for legal reasons, it was renamed SQL. Other Software vendors, including oracle, ingress and Sybase, were receptive of the relational model and also developed SQL-based products.
In 1986, the ANSI standardized SQL and in 1987 the ISO standardized it. The early standards were not complete, leaving some features to be defined by the user or "implementer defined". Later revisions have advaned hte language to include object-relational concepts, integrity management and call level interfaces.
SQL provides standards for
- The language used to construct and manipulate database tables
- Schema for defining, administerign and manipulating data
- Defining data types, triggers, recursive queries
- Schema for defining, administerign and manipulating of objects
