Many of the applications that a Web developer wants to use can be made easier by the use of a standardized database to store, organize, and access information. MySQL is an Open Source (GPL) Standard Query Language (SQL) database that is fast, reliable, easy to use, and suitable for applications of any size. SQL is the ANSI-standard database query language used by most databases (though all have their nonstandard extensions).
MySQL can easily be integrated into Perl programs by using the Perl DBI (DataBase Independent interface) module. DBI is an Application Program Interface (API) that allows Perl to connect to and query a number of SQL databases (among them MySQL, mSQL, PostgreSQL, Oracle, Sybase, and Informix).
If you installed Linux as suggested in Chapter 2, MySQL and DBI are already installed.