Writing the code for an application is just one step toward putting that application into production and then maintaining the code base. It is not possible within the scope of this book to fully address the entire life cycle of application design, development, and deployment. I do have room, however, to offer some ideas and advice about the following topics:
When you compile PL/SQL program units, the source code is loaded into the data dictionary in a variety of forms (the text of the code, dependency relationships, parameter information, etc.). You can then use SQL statements to retrieve information about those program units, making it easier to understand and manage your application code.
Starting with Oracle Database 10g, Oracle has added significant new and transparent capabilities to the PL/SQL compiler. The compiler will now automatically optimize your code, often resulting in substantial improvements in performance. In addition, the compiler will provide warnings about your code that will help you improve its readability, performance, and/or functionality.
Oracle automatically manages dependencies between database objects. It is very important to understand how these dependencies work, how to minimize invalidation of program units, and how best to recompile program units.
Testing our programs to verify correctness ...