Data Modeling

The Data modeling answers of exact questions which are relevant to any data procedure application. What are the main data objects to be processed through the system? What attributes describe the object and what is the composition of each data object? Where do the objects presently reside? What are the relationships among other objects and each object? What is the relationship among the objects and the processes which transform them?

To answer these questions data modeling techniques make use of the entity relationship diagram known as ERD. The ERD define in detail later in this section enables a software engineer to recognize their relationships and data objects using a graphical notation. In the circumstance of structured analysis the ERD describes all data which are stored, input, transformed and produced within an application.

The entity-relationship diagram focuses solely on data and therefore satisfies the first operational analysis principle representing a data network which exists for a given system The ERD is especially useful for applications in that data and the relationships which govern complex are data. Unlike the data flow diagram data modeling considers data independently of the processing which transforms the data.