Posts tagged ERD
Extracting Business Knowledge From Data Models
Mar 4th
Recently, I was following a discussion on extracting business knowledge from UML models. UML models, UML models, and more UML models.
Slowly a thought was emerging from my soaky brain:
hey dude, data models are models too.
In fact, a data model doesn’t always have to be represented by an ERD diagram.
It is also very feasible to diagram a data model using UML class diagrams. It even gets better when you stereotype your classes <<table>>. This enables code generation software to automagically recognize the stereotypes and – for example – generate SQL script for you.
Why on earth that could be remotely interesting?
Because your model is independent from its physical representation.
This way, you can “extract” a model from the physical database, introduce some enhancements, and re-apply the enhancements to the original physical database.
It enables you to enforce an uniform use of naming conventions.
Conceptual and Storage Model
Dec 27th
The most common model is the data model. Deep in the application architecture a physical model can be found, which is a straight representation of the database (ERD diagram).
More superficially, in the core of the application architecture, a conceptual representation of the same data model can be found (UML diagram). However, it should be kept in mind that both are derived from the same underlying data model, thus are essentially the same. As a result mapping from one to another is relatively straight forward (Data Source Explorer).