Advanced Oracle PL/SQL Programming with Packages

17.5. Implementing PLVhlp

I hope that you put PLVhlp to use in your environment; the earlier sections in this chapter should provide a clear guide to doing so. My objective with this book, however, is to also help you develop a philosophy and perspective on your PL/SQL development so that you can build your own utilities like PLVhlp. The rest of this chapter explores the issues, technical challenges, and solutions I encountered in my implementation of PLVhlp.

To show the iterative, spiraling nature of software development, I will step through the implementation of PLVhlp in two stages. In stage one, I build a relatively simple, but effective working model of a script to deliver online help. This version is based on SQL and works only in the SQL*Plus environment. In the second stage, I build a more comprehensive, flexible, and feature-rich online help architecture based on PL/SQL packages (PLVhlp, of course).

17.5.1. Principles for Online Help

The great thing about PL/SQL is that you can use it darn near anywhere: UNIX servers in SQL*Plus, Oracle Forms, home pages on the Internet... you name it and PL/SQL rears its pretty face. Furthermore, the scope of PL/SQL will also almost certainly expand over the years as well, as it becomes one of the key enabling technologies for application partitioning in n-tier environments (now it's three-tier, but why not four- or five-tier? The more layers the better?).

The ubiquitousness of PL/SQL implies to me at this point in time that I want ...