SQL Overview

An abbreviation of structured query language, and pronounced see-kwell, SQL is a standardized query language for requesting information from a database. The original version called SEQUEL (structured English query language) was designed by an IBM research centre in 1974 and 1975. SQL was first introduced as a commercial database system in 1979 by Oracle Corporation. Historically, SQL has been the favourite query language for database management systems.

Although there are different dialects of SQL, it is nevertheless the closest thing to a standard query language that currently exists. In 1986, ANSI approved a rudimentary version of SQL as the official standard, but most versions of SQL since then have included many extensions to the ANSI standard. In 1991, ANSI updated the standard. The new standard is known as SAG SQL.

Actually though it is not a programming language - SQL is actually a simple language. It has a limited number of commands and those commands are very readable and are almost structured like English sentences so are relatively easy to interpret.

In the UK, regarding the terms quoted in IT jobs advertised, SQL is ranked third. In the three months to the end of April 2009, there were 14,500 SQL related jobs advertised. This was half the number of jobs in the same period in 2008.

The average salary for SQL related jobs advertised in the UK is around £40,000. SQL Developer jobs are the most popular and are highly sought after. Interviews for these roles can often include practical questions and challenges related to SQL to assess the candidates technical knowledge and skills. You can find the most common SQL interview questions here.

The Structured Query Language (SQL) is the language of databases. All modern relational databases, including Access, FileMaker Pro, Microsoft SQL Server and Oracle use SQL as their basic building block. In fact, it’s often the only way that you can truly interact with the database itself. All of the fancy graphical user interfaces that provide data entry and manipulation functionality are nothing more than SQL translators. They take the actions you perform graphically and convert them to SQL commands understood by the database.