Logical data modeling is the intermediate step between the Conceptual data modeling and the Physical data modeling. Logical data models represent the abstract structure of a domain of information. They are often diagrammatic in nature and are most typically used in business processes that seek to capture things of importance to an organization and how they relate to one another. Once validated and approved, the logical data model can become the basis of a physical data model and form the design of a database.
The diagram below is a partially expanded view of a data model of a sales system. The term ‘Sales system’ denotes the name of the system to be modeled. The next level of labels customer data, supplier data, Inventory data, Billing represents the conceptual data model. The level below that represents the logical data model. The level below the logical data model is the physical data level.