A question that I’m sometimes asked is “where’s my MD.050 in OUM?” For those not familiar with an MD.050, it serves the purpose of being a Functional Design Document (FDD) in one of Oracle’s legacy Methods.
Functional Design Documents have existed for many years with their primary purpose being to describe the functional aspects of one or more components of an IT system, typically, a Custom Extension of some sort.
So why don’t we have a direct replacement for the MD.050/FDD in OUM? In simple terms, the disadvantage of the MD.050/FDD approach is that it tends to lead practitioners into “Design mode” too early in the process. Whereas OUM encourages more emphasis on gathering, and describing the functional requirements of a system ahead of the formal Analysis and Design process.
So that just means more work up front for the Business Analyst or Functional Consultants right?
Well no…..the design of a solution, particularly when it involves a complex custom extension, does not necessarily take longer just because you put more thought into the functional requirements. In fact, one could argue the complete opposite, in that by putting more emphasis on clearly understanding the nuances of functionality requirements early in the process, then the overall time and cost incurred during the Analysis to Design process should be less.
In short, as your understanding of requirements matures over time, it is far easier (and more cost effective) to update a document or a diagram, than to change lines of code.
So how does that translate into Tasks and Work Products in OUM?
Let us assume you have reached a point on a project where a Custom Extension is needed. One of the first things you should consider doing is creating a Use Case, and remember, a Use Case could be as simple as a few lines of text reflecting a “User Story”, or it could be what Cockburn1 describes as a “fully dressed Use Case”.
It is worth mentioned at this point the highly scalable nature of OUM in the sense that “documents” should not be produced just because that is the way we have always done things. Some projects may well be predicated upon a base of electronic documents, whilst other projects may take a much more Agile approach to describing functional requirements; through “User Stories” perhaps.
In any event, it is quite common for a Custom Extension to involve the creation of several “components”, i.e. some new screens, an interface, a report etc. Therefore several Use Cases might be required, which in turn can then be assembled into a Use Case Package.
Once you have the Use Cases attributed to an appropriate (fit-for-purpose) level of detail, and assembled into a Package, you can now create an Analysis Model for the Package. An Analysis Model is conceptual in nature, and depending on the solution being developing, would involve the creation of one or more diagrams (i.e. Sequence Diagrams, Collaboration Diagrams etc.) which collectively describe the Data, Behavior and Use Interface requirements of the solution. If required, the various elements of the Analysis Model may be indexed via an Analysis Specification.
For Custom Extension projects that follow a pure Object Orientated approach, then the Analysis Model will naturally support the development of the Design Model without any further artifacts. However, for projects that are transitioning to this approach, then the various elements of the Analysis Model may be represented within the Analysis Specification.
If we now return to the original question of “Where’s my MD.050”. The full answer would be:
An alternative answer for a relatively simple Custom Extension would be:
1 Cockburn, A, 2000, Writing Effective Use Case, Addison-Wesley Professional; Edition 1