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The Microsoft.BusinessData.MetadataModel namespace contains classes, interfaces, and enumerations that are used in the design of external systems, external content types, methods, and associations between external content types.
DuplicateMetadataObjectException Represents an exception that is thrown when one or more metadata objects have field values that are equal in a context where this is not allowed.
ExceededMetadataObjectLimitException Represents the exception that is thrown when the number of metadata objects of a particular type that are loaded into the cache exceeds a predefined limit, or if the number of metadata objects related to another metadata object exceeds a predefined limit.
InvalidMetadataObjectException Represents the exception that is thrown if the metadata object you are trying to access or create is not valid.
InvalidMetadataPropertyException Represents the exception that is thrown if a metadata property is not valid.
MetadataException Represents a base exception class that is thrown when the runtime engine encounters miscellaneous issues with Microsoft Business Connectivity Services (BCS) metadata.
MetadataObjectNotFoundException Represents the exception thrown if the requested metadata object cannot be found in the Business Data Connectivity (BDC) service.
MissingMetadataPropertyException Specifies the exception that is thrown when a particular metadata object instance does not have an expected property.
IAccessControlledMetadataObject Represents a metadata object to which access can be restricted.
IAction Defines methods and properties on an action.
IActionParameter Defines the parameters that the action URL accepts.
IAssociation Represents a relationship between two or more related external content types within external systems.
IAssociationGroup Represents a relationship between external content types by grouping related association objects.
IAssociationReference Represents a reference to an association.
IDataClass Defines properties and methods that support a data class that represents the base class of all external content types.
IEntity Represents an external content type such as Customer or Product, in a line-of-business (LOB) application.
IEntityReference Represents a reference to an external content type.
IField Represents a data element in a View.
IFilterDescriptor Describes a filter.
IIdentifier Defines the properties of an external content type identifier.
IIdentifierReference Represents a reference to an identifier.
ILobSystem Represents an external system.
ILobSystemInstance Represents a LobSystemInstance.
ILobSystemStruct Represents the type information of an external system.
IMetadataCatalog Provides access to metadata objects.
IMetadataObject Represents a metadata object.
IMetadataStruct Represents a structure that contains the data fields of a metadata object.
IMethod Represents a method on an external content type.
IMethodInstance Represents stereotypical operation of a method on an external content type.
IParameter Represents the in, in-out, out, and return parameters of each method.
ITypeDescriptor Represents a data structure in the external system.
IView Represents a collection of fields, where fields are the data members of an external content type.
DirectionType Represents a direction parameter for methods on external system objects.
FilterType Represents the enumeration that identifies the type of the filter descriptor.
MethodInstanceType Represents the type of a MethodInstance.
SystemType Represents an enumerator that identifies the type of the external system object.
TypeDescriptorFlags Describes flags for a type descriptor, such as whether the type descriptor is read-only, or whether the type descriptor is used as a field in a creator view.