A data model visually represents the nature of data, business rules governing the data, and how it will be organized in the database. A data model is comprised of two parts logical design and physical design
For example Company ABC is planning to build a guest house(database) and it calls the building architect(data modeler) and projects its building requirements (business requirements). Building architect(data modeler) develops the plan (data model) and gives it to company ABC. Finally company ABC calls civil engineers(DBA) to construct the guest house(database)
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