Why Use an Entity Data Model?

Well-designed databases can pose a problem for developers.

In the data world, a database is designed for maintainability, security, efficiency, and scalability. Its data is organized in a way that satisfies the demands of good database design, yet provides challenges for the developer who needs to access that data.

Note: Entity Data Model is a concept. The Entity Framework has a particular implementation that is realized as the EDMX file at design time. At runtime, the EDMX file is broken up into three separate XML files. For the sake of clarity, this book will simply refer to the EDM or Entity Data Model (or simply “the model”) when discussing the Entity Framework’s implementation. But keep in mind that the EDM literally refers to the concept of using some type of model to represent your entities in an application.

The EDM follows the concept of Entity Relationship Modeling, but in the Entity Framework, it moves the model into XML files that are used by the Entity Framework runtime.

With an EDM in place, developers can focus on their business objects even when retrieving data from the database or persisting it back to the database. You, the developer, will not have to worry about the structure of the database, the names of the tables or views, or the names of stored procedures or their required parameters. Nor will you have to create the objects necessary for making connections to the database, or be concerned with the schema of the returned data and then transform the results into objects to use in your code.

You will simply work against your conceptual model and the classes that represent the model’s entities. And when you do so within the scope of the Entity Framework, the Entity Framework runtime will handle database connections, database command generation, query execution, object materialization, and the details of persisting changes back to the database.