Metadata Workspace Overview
The ADO.NET MetadataWorkspace class is a central runtime API that enables developers to access Entity Data Model (EDM) metadata in the context of an application. The metadata workspace aggregates metadata from specific item collections that are individually responsible for loading different types of metadata.
The following diagram illustrates the relationships between the MetadataWorkspace class and its respective item collections.
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The item collections load metadata from persistent resources such as XML files (CSDL, SSDL, and MSL) or common language runtime (CLR) assemblies. Each resource represents a different type of metadata. For more information about the item collections, see Item Collections (Metadata).
There are four types of metadata corresponding to different models in an application that uses the ADO.NET Entity Framework:
The object model: Represents the static representation of the classes that are optionally used as a concrete object-realization of the conceptual model.
The conceptual model: Represents the conceptual entities that reflect the domain model for the ADO.NET application.
The storage (database) model: Represents the logical model for the target database expressed in terms of the EDM.
The mapping model: Represents the mapping between the conceptual entities and the logical database model.
ADO.NET loads metadata from CLR classes for the object model, from conceptual schema definition language (CSDL) files for the conceptual model, from store schema definition language (SSDL) files for the storage model, and from mapping specification language (MSL) files for the mapping model.