SQL - technical definition

(Structured Query Language) Pronounced "S-Q-L" or "see-quill," a language used to interrogate and process data in a relational database. Originally developed by IBM for its mainframes, all database systems designed for client/server environments support SQL. SQL commands can be used to interactively work with a database or can be embedded within a programming language to interface to a database. Programming extensions to SQL have turned it into a full-blown database programming language, and all major database management systems (DBMSs) support the language.

ANSI standardized SQL, but most database management systems (DBMSs) have some proprietary enhancement, which if used, makes SQL non standard. Moving an application from one SQL database to another may require tailoring to convert some commands. The age old dilemma in this business! See MDX, CLI, ODBC and IDAPI.

The following SQL query selects customers with credit limits of at least $5,000 and puts them into sequence from highest credit limit to lowest. The blue words are SQL verbs. See SPUFI.

       select name, city, state, zipcode
       from customer
       where creditlimit > 4999
       order by creditlimit desc