Basic Concept: Identity and the Compound Identifier
asdasddThe CompoundIdentifier serves two purposes. First, it has a locally-scoped identifier (ReferenceId) which allows its parent object to be used by reference within a given dataset. Second, it enables the association of multiple unique identifiers and their origin information (UniqueId) to an object. This results in an enhanced exchange of data between different systems because each system can include its internal, unique identifier for an object.
Systems vary in the way they choose to construct unique identifiers. It is for this reason, that the UniqueId class uses a combination of string (Id) and enumeration (CompoundIdentifierTypeEnum) to fully describe the unique identifier.
Almost as important is the need to capture the originating source, or issuing authority of the identifier. Again, a combination of string (Source) and enumeration (IdSourceTypeEnum) are used to fully describe the identifier's source.
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The ContextItem System Data Model: Bird's-eye view
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