Chapter 6: Conceptual Design

Overview

In the rush to design and develop software, conceptual design is usually one of the easiest steps to overlook. Everyone understands the importance of analyzing business and user requirements before embarking on software coding, and few people will question the wisdom of following proper database design models due to the difficulty in implementing changes later on in the process. On the contrary, convincing developers to follow a proper conceptual-logical-physical design model for software seems to be an uphill battle, but it’s a battle that needs to be fought nonetheless.

The newest models in software development, such as Extreme Programming (XP) and the Rational Unified Process (RUP), have strong conceptual design elements. For instance, RUP relies on use cases and analysis models to create a conceptual design model. The conceptual model created during that process then gets transformed into a formal model for implementation.

Author's Note

A use case is a Unified Modeling Language (UML) document or diagram that describes all of the potential ways a user will need to interact with the system. These use cases are sometimes referred to as user stories.

The temptation exists for many developers to jump right into coding once the business requirements are finalized. Of course, this is understandable because many developers perceive coding as the “fun” part of the software development process. This bad behavior is reinforced by some managers who place unrealistically short deadlines on projects and by the tendency for experimental prototypes to become real products without a thought given to proper design.

In Chapter 5, we saw how Object Role Modeling (ORM) could be used to create the conceptual design for databases using the Conceptual Schema Design Procedure (CSDP). In this chapter, we will move beyond the conceptual schema to create an overall conceptual design for our application. We will take into account the business, user, and operational requirements identified earlier in the design phase to create the ideal overall solution.