|Lesson 5||Data modeling techniques|
|Objective||Explain the importance of data modeling techniques. |
Data Modeling Techniques
Off-the-shelf database software is most useful if it is customized to the purpose it was purchased to serve.
In order to customize and build the database, you will need to build a model of what the data relationships will look like.
It is important to model data before beginning database development because database structure is based on the relationships that are to be created among data elements.
Who and why?
Data modeling is primarily the task of database developers, or system analysts, and refers to the process of organizing the hierarchy or
relational structure for efficient storage and access of the data. Modeling is the most critical part of database development. Similar to an
architect's layout for a new house, modeling addresses all issues for database design before construction begins. Modeling is the foundation from which the database will be built.
Create the groupings
Modeling involves the logical grouping or assembling of information. For example, in a Human Resources system, there are a variety of data
elements that can be grouped, such as names, addresses, employee benefits, compensation, and performance ratings.
These data elements need to be tied together in logical groupings based on the predictable and consistent relationships that exist between them.
When grouping data, a balance must occur between the physical speed of access and its ease use (querying the database). In other words, lumping lots of data into one large table makes
it extremely easy to query. But large grouped data means a huge file size, and the larger the size, the slower the system can process it.
Anyone can model data, but it takes skill to strike the optimal balance between speed and ease of use.
Data modeling also establishes processes to update data element groupings when an individual data element is changed. For example, in the
Human Resources system, changes in benefits coverage can be programmed to automatically generate payroll changes.
The purpose of such modeling is to describe the information relationships and processes so that programmers can build a system that matches the data and process requirements.
Some newer database applications actually generate code based on the models that are created by database developers. The code can then be modified so that the system does precisely what is desired.
There are a number of software products such as Rational Software's Rational Rose that assist developers with data modeling.
In the next lesson, your task is to learn the types and examples of security software options.
Data Modeling - Quiz
Click the Quiz link below to check your learning of principles and characteristics of databases.
Data Modeling - Quiz