Perl (Programming the Perl DBI)

1.2. Perl

Perl is a very high-level programming language originally developed in the 1980s by Larry Wall. Perl is now being developed by a group of individuals known as the Perl5-Porters under the watchful eye of Larry. One of Perl's many strengths is its ability to process arbitrary chunks of textual data, known as strings , in many powerful ways, including regular-expression string manipulation. This capability makes Perl an excellent choice for database programming, since the majority of information stored within databases is textual in nature. Perl takes the pain of manipulating strings out of programming, unlike C, which is not well-suited for that task. Perl scripts tend to be far smaller than equivalent C programs and are generally portable to other operating systems that run Perl with little or no modification.

Perl also now features the ability to dynamically load external modules , which are pieces of software that can be slotted into Perl to extend and enhance its functionality. There are literally hundreds of these modules available now, ranging from mathematical modules to three-dimensional graphics-rendering modules to modules that allow you to interact with networks and network software. The DBI is a set of modules for Perl that allows you to interact with databases.

In recent years, Perl has become a standard within many companies by just being immensely useful for many different applications, the "Swiss army knife of programming languages." It has been heavily used by system administrators who like its flexibility and usefulness for almost any job they can think of. When used in conjunction with DBI, Perl makes loading and dumping databases very straightforward, and its excellent data-manipulation capabilities allow developers to create and manipulate data easily.

Furthermore, Perl has been tacitly accepted as being the de facto language on the World Wide Web for writing CGI programs. What's this got to do with databases? Using Perl and DBI, you can quickly deploy powerful CGI scripts that generate dynamic web pages from the data contained within your databases. For example, online shopping catalogs can be stored within a database and presented to shoppers as a series of dynamically created web pages. The sample code for this book revolves around a database of archaeological sites that you can deploy on the Web.

Bolstered by this proof of concept, and the emergence of new and powerful modules such as the DBI and the rapid GUI development toolkit Tk, major corporations are now looking towards Perl to provide rapid development capabilities for building fast, robust, and portable applications to be deployed within corporate intranets and on the Internet.