Data Model

A data model organizes data by similar elements and shows how these elements relate to one another.

Data Modeling
These models contain a lot of information that pertains to the real world so it has to represent reality as much as possible and be easy to read. The main goal of data models is to support the development of information systems by providing the definition and format of data. A data model determines the structure of data. Data model is based on Data, Data relationship, Data semantic and Data constraint. These models form the basis for data parsing, and use metadata to organize the data. There are three basic types of data models that are used in practice; these are Conceptual data models, Logical data models, and Physical data models.

Conceptual Data Models
Conceptual Data Models are also known as domain models and are used to explore domain concepts with project stakeholders.

Logical Data Models
Logical Data Models are used to explore the domain concepts and how their relationships. LDMs depict logical entity types, data attributes that describe the entities and what relates multiple entities.

Physical Data Models
Physical data models are used to design the internal schema of a database, depicting the data tables, the data columns of those tables, and the relationships between the tables. PDMs often prove to be useful on both Agile and traditional projects and as a result the focus of this article is on physical modeling.