Chapter 20. Custom Applications

If you are generating dynamic content, you will need to do some kind of programming, even if it is simply inserting HTML-like tags that generate predefined dynamic responses. Custom programming is a likely source of bottlenecks and crashes, and in this chapter we go over some common problems.


Programmers vary widely in ability and aesthetics, as all humans do, but when you are paying them, it makes a big difference to you how good they are. The most important point to remember is the best programmers write the least code, and what little code they write, others can easily read and understand. The reason they write the least code is they can clearly see a simple way to accomplish what they need to do. It is amusing that many large software companies grade their programmers on the number of lines of code they write per day. This is exactly the opposite of efficiency. Good programmers often spend their day removing unnecessary and complicated lines of code others have written, so on a really good day, they may actually have produced a negative number of lines of code!

CGI Programs

While plain HTML documents stored on your web server can contain whatever text you like, that text is static. Everyone who requests that document through a web browser will get exactly the same document. Quite often, however, you’d like to customize the response for a particular user. For example, a retail chain store might want to query a database for the user ...

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