Choosing A Scripting Language For Your Web Site.

Building Web pages and databases today is easier than ever before. The real trick is expertly integrating the two together so that some Web pages can let visitors input data from HTML forms while other pages display database information. The answer lies in server-side scripting frameworks such as ASP.NET, ColdFusion, JSP, PHP and Perl. These frameworks let you write HTML documents with islands of code embedded in them.

<ASP.NET is the first major overhaul of the original Active Server Pages (ASP). Sun's JSP improved on ASP (for example, JSP documents are compiled the first time they are loaded, which speeds response time for each subsequent visitor). ASP.NET includes many of the enhancements found in JSP. ASP.NET ships with the .NET Framework, available from http://msdn.microsoft.com/net.

ColdFusion by Macromedia (formerly from Allaire) was one of the earliest commercial Web/database solutions. Since its introduction, it has grown to a full-fledged application server, with capabilities comparable to ASP.NET and JSP/Java Servlets. You'll find a trial edition of ColdFusion at www.macromedia.com.

JSP (Java Server Pages) combines HTML and the Java programming language. You can add bits of Java, which will execute on the server, to your HTML pages. Java is completely different from (but often confused with) JavaScript, a lightweight language that executes on browsers and uses syntax similar to Java's. You can get JSP by downloading and installing Tomcat, the official reference implementation of JSP and Java Servlets. Tomcat is open-source and can be found at http://jakarta.apache.org/tomcat.

PHP (www.php.net) is a scripting language with syntax similar to that of Perl. It was originally written in Perl but was ported to C. PHP is more mature than ASP or JSP. PHP markup is interspersed with bits of HTML. PHP code is marked off using the delimiters. Although PHP has a simple syntax for connecting to databases, each database has its own set of functions, prefixed with the name of the database. Contrast this with ASP.NET, ColdFusion, JSP, and Perl, in which the functions are the same, regardless of the database you connect to. In those languages, the only thing you need to change is your database connection string. There is one exception to this in ASP.NET: In addition to the framework's generic data provider (the OLE DB provider), ASP.NET offers an optimized provider for SQL Server. MySQL (www.mysql.com), which is open-source, is the database server most commonly associated with PHP, and you can use the mysql_* functions to interact with this database.

Perl (www.perl.com) is a powerful, versatile, but not very elegant scripting language. Its attractiveness is the many different things you can do with Perl. Aside from Web development, you can use Perl for log-file analysis and data conversion, for example. Perl has great support for Web programming and a great database-access API called DBI.

You can use any of the solutions covered here to develop great Web/database applications. So how do you select the one to use if you're starting from scratch?

The best advice, once you've figured out what you want to do, is to look for similar Web/database applications that are successful. What approach did they use? In some cases, their software may be available, and you can customize it. For example, the high-traffic news and discussion site Slashdot (www.slashdot.org) uses Perl and MySQL. The code that drives the site is called Slash. You can download Slash for free at http://slashcode.com. Whether or not a site has code you can take and customize, you can gain valuable information just by looking at what the developers chose to drive the site. Here's a hint: Even if the developers don't explicitly tell you what they use, the filename extensions on their Web site can help.

If you can find a few sites similar to the one you want to build, compare the performance and features. You can even try sending mail to the sites' Webmasters and get some war stories about their choices of software. You can also find a discussion list where Webmasters hang out. Try http://directory.google.com/Top/Computers/Programming/Internet/Resources for Web development resources.