Introduction to SQL
Added 29 Jul 2008
The SQL language and relational database
systems based on it are one of the most important foundation
technologies in the computer industry. Over the last two decades, SQL
has grown from its first commercial use into a computer product and
services market segment worth tens of billions of dollars per year, and
SQL stands today as the standard computer database language.
Literally hundreds of database products now support SQL, running on
computer systems from mainframes to personal computers and even
handheld devices. An official international SQL standard has been
adopted and expanded twice. Virtually every major enterprise software
product relies on SQL for its data management, and SQL is at the core
of the database products from Microsoft, Oracle, and IBM, the three
largest software companies in the world. SQL is also at the heart of
open-source database products that are helping to fuel the popularity
of Linux and the open-source movement. From its obscure beginnings as
an IBM research project, SQL has leaped to prominence as both an
important computer technology and a powerful market force.