What is Data Modeling
Data modeling is the process of creating data models for data to be stored in a database.
It is the first step in database design, and highly conceptual. It describes not only the data contained in the database, but also the relationships between the data items, and the constraints on the data.
Data modeling can have many applications, but is mainly used to express a company’s business requirements. There are three main types of data models: conceptual (defining what the system will contain); logical (defining how the system should be implemented, developing rules and data structures); and physical (describing how the system will be implemented).