An .edmx file is automatically added to an application that references an ADO.NET Data Services service. In this case, the .edmx file contains an edmx:DataServices node, not an edmx:Runtime node. For more information, see WCF Data Services.
Storage Model Content (edmx:StorageModels): This section describes the target database schema and is written in storage schema definition language (SSDL). For more information, see SSDL Specification and EntityContainer Element (SSDL).
Conceptual Model Content (edmx:ConceptualModels): This section defines the entity types, complex types, associations, entity containers, entity sets, and association sets in the application domain. This section is written in conceptual storage definition language (CSDL). For more information, see CSDL Specification and EntityContainer Element (CSDL).
Mapping Content (edmx:Mappings): This section describes the mapping between the conceptual model and the target database, and is written in mapping specification language (MSL). For more information, see MSL Specification.
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