SQL Tutorial - SQL Query Reference and Programming Examples. SQL (Structured Query Language) is a computer language aimed to store, manipulate, and query data stored in relational databases. The first incarnation of SQL appeared in 1974, when a group in IBM developed the first prototype of a relational database. The first commercial relational database was released by Relational Software (later becoming Oracle). Standards for SQL exist. However, the SQL that can be used on each one of the major RDBMS today is in different flavors. This is due to two reasons: 1) the SQL command standard is fairly complex, and it is not practical to implement the entire standard, and 2) each database vendor needs a way to differentiate its product from others.
In this tutorial, such differences are noted where appropriate. This SQL programming help site lists commonly-used SQL statements, and is divided into the following sections: For each command, the SQL syntax will first be presented and explained, followed by an example. Cheat Sheet : All Cheat Sheets in one page. Cheat Sheet : All Cheat Sheets in one page. MySQLTuner. MySQLTuner.pl.