The correct pronunciation of SQL is a contentious issue within the database community. In its SQL standard, the American National Standards Institute declared that the official pronunciation is “es queue el.” However, many database professionals have taken to the slang pronunciation “sequel.” The choice is yours.
SQL comes in many flavors. Oracle databases use its proprietary PL/SQL. Microsoft SQL Server makes use of Transact-SQL. All of the variations are based upon the industry standard ANSI SQL. This introduction uses ANSI-compliant SQL commands that work on any modern relational database system.