SUGI 28: Beyond Debugging: Program Validation

"Act in haste and repent at leisure; code too soon, and debug forever." Raymond Kennington In their paper on debugging, Lora Delwiche and Susan Slaughter say that good debuggers make good programmers. Let's take that one step further to say that good analysts and problem-solvers make good programmers. Just because a SAS® program is free of errors, warnings, notes, and bugs does not guarantee that the program is doing what it is supposed to do. This tutorial addresses the process that follows debugging: program validation. It covers techniques for ensuring that the logic and intent of the program is correct, that the requirements and design specifications are met, and that data errors are detected. It also discusses fundamental SAS program design issues that give purpose and structure to your programming approach. This paper will address: the definitions of verification, validation, testing, and debugging, as well as the structure of the Software Development Life Cycle (SDLC). It will illustrate how the SAS system can be used to help satisfy the requirements of your SDLC and accomplish the tasks of verification and validation. Since as much as 80% of a programmer’s time is invested in testing and validation, it’s important to focus on tools that facilitate correction of syntax, data, and logic errors in SAS programs. The presentation focuses on wide variety of SAS features, tips, techniques, tricks, and system tools that can become part of your routine testing methodology.