ADO.NET Entity Data Model Designer Overview
The ADO.NET Entity Data Model Designer (Entity Designer) is a visual tool that enables point-and-click modification of an EDM. You can use the Entity Designer to visually create and modify entities, associations, mappings, and inheritance relationships. You can also validate an EDM.
The Entity Designer works together with the Entity Data Model Wizard and Update Model Wizard to allow you to generate, edit, and update an EDM.
The Entity Designer consists of the following components:
A visual design surface for editing the conceptual model. You can create, modify, or delete entities and associations.
A Mapping Details window for viewing and editing mappings. You can map entity types or associations to database tables, columns, and stored procedures. For more information, see Mapping Details Window.
A Model Browser window that provides tree views of the conceptual model and the storage model. For more information, see Model Browser Window.
Toolbox controls for creating entities, associations, and inheritance relationships.
The Entity Designer is integrated with Visual Studio components.
The Entity Designer works with an .edmx file. An .edmx file is the combination of three EDM metadata files: the conceptual schema definition language (CSDL), store schma definition language (SSDL), and mapping spcification language (MSL) files. When you run the Entity Data Model Wizard, an .edmx file is created and added to your solution. This file is automatically opened in the Entity Designer when the Entity Wizard finishes. You can also open the .edmx file in the Entity Designer by double-clicking it in Solution Explorer.
The following screenshot shows an .edmx file opened in the Entity Designer. The screenshot shows the visual design surface for creating and editing the conceptual model, the Model Browser window, and the Mapping Details window.
For detailed information about how to use the Entity Designer, see Entity Data Model Tools Tasks.
Entity Framework Features Not Supported by the Entity Designer
The following are Entity Framework features that are not currently supported by the Entity Designer.
Multiple entity sets per type.
Creating entity sets for non-root types.
Table-per-concrete class mapping.
Using EntityType properties in mapping conditions.
Editing storage model elements.
Unmapped abstract types. When you create an abstract entity type with the Entity Designer, the type must be mapped to a table or view.
Creating conditions on association mappings.
Mapping associations directly to stored procedures. Mapping many-to-many associations is not supported. You can indirectly map other associations to stored procedures along with entity types by mapping the appropriate navigation properties to stored procedure parameters.
Creating conditions on Function Import mappings.
Specifying a parameter on an update function to return the number of rows affected. The Entity Designer does not expose a user interface for specifying this output parameter. However, you can manually edit the .edmx file so that the update function will handle this output parameter.
Models that contain references to other models.
Attempting to use these features with the Entity Designer, or making manual edits to the .edmx file, might result in an error that stops the Entity Designer from displaying the .edmx file. In this case, you will be prompted to open the file with the XML Editor.
For more information about these features, see Entity Data Model Mapping Scenarios (Application Scenarios).