Identification, Versioning, Maintenance and Reference¶
The identification structure of DDI objects is core to the functioning of the standard. The purpose of the DDI identification structure is to:
- Uniquely identify major objects in a persistent manner to ensure accurate reference and retrieval of the object content
- Provide context for objects where an understanding of related object types within a packaging structure is essential to the understanding of the object (i.e., a specific classification within a classification scheme)
- Manage metadata object change over time
- Support the range of object management used by different organizations
- Support early and late binding of references
- Support interaction with closely related standards, in particular ISO/IEC 11179 and SDMX
The identification structure is based on the ISO/IEC 11179 structure that requires a three-part means of unique identification.
OBJECT | ISO/IEC 11179 | DDI |
---|---|---|
Agency Identifier | A unique identifier for the agency managing the object | A unique identifier for an agency registered with the DDI Alliance. The agency may have multiple sub-agency extensions managed within the DDI Registry or within the primary agency. An agency and sub-agency are separated by an “.”. |
Unique ID | A unique identifier of the object within the context of the agency | An identification which is unique within
|
Version Number | A version number of the object to track change over time | A version number with any number of extensions separated by a “.”. |
This three part structure is the equivalent of a unique persistent identifier for an object, such as described by DOIs and other similar structures. Note that while use of a version number with a DOI is optional, based on local practice, the Version Number in DDI is required due to the need to manage metadata within a dynamic workflow over time.