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Issue 7.3

FEATURE

How To Read A Data Model

Understanding a Data Model Helps in Understanding Requirements and Application Design

Issue: 7.3 (March/April 2009)
Author: Craig Boyd
Author Bio: Craig Boyd is currently a Sr. Data Modeler for a large well known financial institution. But during his twelve years in the IT industry has been everything from a PC Technician to iSeries System Administrator to Programmer and Sr. Technical Lead.
Article Description: No description available.
Article Length (in bytes): 27,528
Starting Page Number: 22
Article Number: 7310
Resource File(s):

Download Icon 7310 graphics.zip Updated: 2009-03-02 13:37:02

Related Link(s): None

Excerpt of article text...

In this article I intend to explain to you what a data model is and how to read one.

Within the field of data modeling there are several kinds of models and in order to make sure we are all talking about the same thing I need to briefly lay out, in general terms, the kinds of Information Models that exist. For the purpose of this article I will use a fictitious movie rental company, called "Movies R Us".

For the sake of clarity let me define a few terms. An entity at a high level represents a general concept, but as we move further down into lower level models it will become a more concrete or discrete concept. For example, a high level entity might be "Product" and then a little lower it may become a couple different entities like "Movie" and "Consumable Product."

...End of Excerpt. Please purchase the magazine to read the full article.