Database Models

In this paper I will be discussing the differences and similarities of the three database models we have talked about in class the Entity-Relationship, Object model, and the UML modeling. First let’s look at the definition of the three models.

The Entity- Relationship Model is used to visually represent data objects and is used for database design. It is easy to understand which makes it easier to communicate the design to the end user. The form used in the ER model can easily be transformed into relational tables. (Information Technology Services [ITS], 2004)

Another database model we went over in class is the Object Model. There are three concepts to understanding the Object Models one of them being the Data Abstraction which is the process of condensing data down to its essentials. Another one is the Inheritance in the object model is the means of defining one class in terms of another. The third concept in the object model is the Encapsulation which is the concept of including processing or behavior with the object instances defined by the class. Encapsulation allows code and data to be packaged together.

The third database model would be the UML model that stands for Unified Modeling Language used for writing software blue prints. The UML can be used to visualize, specify, construct, and document the artifacts of a software-intensive system. (Safari Tech Books Online, 2002, chap. 2)

Some of the similarities in the database model are that all three can be used in the database design process in some way. In our previous class DBM 380 we used the ER model for our projects even from our preceding projects we can create the database model in an Object or UML model. Of the three database models I find that the Entity Relationship model was the easiest to create and explain to an end user it also transforms effortlessly into relationship tables which worked well in Access. The Object model and UML model seem to be more of a language model than the ER model seems to be more for just databases although the Object model addresses both programming and databases. The UML model is more for intense software programming such as Java programming it would allow you to visualize and document your programming steps before starting the code.