Richard's BLOG

Category: IT   Topic: Business Modelling

In the previous blog entry, I talked about using observational semantics to help focus on modelling the domain of a problem, rather than software.

When the domain to be modelled is big, we bring another technique to bear, too. We build a number of smaller models, each with its own point of view, and then combine these smaller models into a larger model of the whole domain. Each smaller model is built from a certain viewpoint, and captures some aspect of the business.

For example, a business that rents out DVDs and a business that sells health food supplements will both have a point-of-sale aspect, characterized by the exchange of goods or services for money. Both businesses will have rules about adding a sale item to an ongoing sale, for instance, and a point-of-sale model can capture these rules.

By modelling the point-of-sale aspect of your domain separately from other aspects, you can exploit expertise. If someone has become something of an expert in point-of-sale issues on one project, they can carry it over to another project more easily if the point-of-sale aspect is initially kept separate from other aspects of the problem domain.

There are, of course, other ways to partition a big model. We've found modelling different views to be extremely useful in practice, and we think it's underused. That's why it'll make its way into our book.