Identifiable, Versionable, and Maintainable¶
DDI differentiates between a set of element types. Not all objects are individually identifiable, i.e. some objects only have meaning within the context of an identifiable object such as a Label or Description. The remaining objects are Identifiable, Versionable or Maintainable in order to support different levels of metadata management.
Identifiable¶
Identifiable objects are those that can be referenced directly either or inclusion in another object or for the purpose of attaching Other Material or a Note to the object.
Identifiable objects have a unique ID within the context of their specified scope of uniqueness (see Scope of Uniqueness discussion within this section). Their Agency Identification and Version Number match those of the object’s immediate parent Versionable (or Maintainable if there is not a parent Versionable) at the point of creation. This means that if an Identifiable object is created within a version 1 of a parent Versionable and does NOT change its content over time it will retain its Version Number of 1 until the identifiable object itself is altered. It will then change its Version Number to that of its parent Versionable at the time of the alteration.
In other words an Identifiable could go from a Version 1 to a Version 4 without ever having a Version 2 or 3 if the cause for versioning did not involve any change in the Identifiable object within Version 2 and 3 of the parent Versionable.
| Identifiable Object | Extension base is AbstractIdentifiable |
|---|---|
| URN | See URN Structure below |
| @typeOfIdentifier | URN used by Agency [Canonical | Deprecated] |
| Agency | Base sequence of identification. If sequence is used, all are required. |
| ID | |
| Version | |
| UserID | |
| @typeOfUserID | A user specified identification for a specific system such as a DOI or internal search engine. Both the ID and @typeOfUserID must be specified. Version information is optional. |
| @userIDVersion | |
| @typeOfUserVersion | |
| MaintainableObject | |
| TypeOfObject | The Maintainable object containing the Identifiable object. TypeOfObject is required to create Deprecated URN. ID is required for any URN if ScopeOfUniqueness = ”Maintainable”. Version number provides context base. |
| MaintainableID | |
| MaintainableVersion | |
| @inheritanceAction | See Grouping: Inheritance |
| @objectSource | The object source of a resolved reference |
| @scopeOfUniqueness | Scope used by Agency [Agency | Maintainable |
| @IsUniversallyUnique | States the scope of uniqueness for the ID |
| @isIdentifiable | Fixed value = “true” [specifies object base] |
Versionable¶
A Versionable object has the characteristics of an Identifiable object but may be managed over time.
DDI has determined that being able to tack change within the object over time is a requirement, either to understand the relationship to earlier objects of a similar type or to track provenance.
Note that it is up to the individual content provider to determine whether an object is essentially new or is a modification (version) of an earlier object. Versionable objects have a unique ID within the context of their specified scope of uniqueness (see Scope of Uniqueness discussion within this section). Their Agency identificationmatches that of the object’s immediate parent Maintainable at the point of creation.
In other words the Agency of an object does not change simply because it is included by reference in a Maintainable managed by a different agency. The Version number of the object changes each time its content changes. See Versioning for a discussion of when and how this may be implanted within different organizations or projects.
| Versionable Object | Extension base is AbstractIdentifiable |
|---|---|
| URN | See URN Structure below |
| @typeOfIdentifier | URN used by Agency [Canonical | Deprecated] |
| Agency | Base sequence of identification. If sequence is used, all are required. |
| ID | |
| Version | |
| UserID | |
| @typeOfUserID | A user specified identification for a specific system such as a DOI or internal search engine. Both the ID and @typeOfUserID must be specified. Version information is optional. |
| @userIDVersion | |
| @typeOfUserVersion | |
| UserAttributePair | |
| AttributeKey | User defined Key/Value pair used to support interaction of the metadata within the user’s system. |
| AttributeValue | |
| VersionResponsibility | Who within the Agency versioned the object |
| VesionResponsibilityReference | Alternate reference to who versioned the object |
| VersionRationale | Reason for version change (to inform user) |
| BasedOnReference | |
| MaintainableObject | |
| TypeOfObject | The Maintainable object containing the Identifiable object. TypeOfObject is required to create Deprecated URN. ID is required for any URN if ScopeOfUniqueness = ”Maintainable”. Version number provides context base. |
| MaintainableID | |
| MaintainableVersion | |
| @inheritanceAction | See Grouping: Inheritance |
| @objectSource | The object source of a resolved reference |
| @scopeOfUniqueness | Scope used by Agency [Agency | Maintainable |
| @IsUniversallyUnique | States the scope of uniqueness for the ID |
| @isVersionable | Fixed value = “true” [specifies object base] |
| @versionDate | Date/Time of version change |
Maintainable¶
A Maintainable object is a type of packaging and generally takes the form of either a module or scheme.
Modules package metadata focused on specified segments of the Lifecycle for which context is important for understanding.
Schemes are similar to data base tables, containing a stack of similar type objects that many have important contextual relevance to each other, i.e. a classification scheme captured in a DDI Category Scheme. There is one unique form of a Maintainable which is the CodeList. A CodeList is a Maintainable in its own right for the purpose of supporting the statistical production process. However it can only be published within the context of a parent Maintainable Scheme.
All Schemes and Modules may be published within the context of a Study Unit or Group (a collection of Study Units) or as a separate Resource Package item primarily for the purpose of reuse.
| Maintainable Object | Extension base is AbstractMaintainable |
|---|---|
| URN | See URN Structure below |
| @typeOfIdentifier | URN used by Agency [Canonical | Deprecated] |
| Agency | Base sequence of identification. If sequence is used, all are required |
| ID | |
| Version | |
| UserID | |
| @typeOfUserID | A user specified identification for a specific system such as a DOI or internal search engine. Version information is optional. Both the ID and @typeOfUserID must be specified. |
| @userIDVersion | |
| @typeOfUserVersion | |
| UserAttributePair | |
| AttributeKey | User defined Key/Value pair used to support interaction of the metadata within the user’s system. |
| AttributeValue | |
| VersionResponsibility | Who within the Agency versioned the object |
| VesionResponsibilityReference | Alternate reference to who versioned the object |
| VersionRationale | Reason for version change (to inform user) |
| BasedOnReference | |
| Note | Notes related to objects with the maintainable (Payload) |
| Software | Software used to create the Maintainable object (Payload) |
| MetadataQuality | Quality of the metadata in the Maintainable object (Payload) |
| MaintainableObject | Same as Identifiable Object |
| @inheritanceAction | See Grouping: Inheritance |
| @objectSource | The object source of a resolved reference |
| @scopeOfUniqueness | Scope used by Agency [Agency | Maintainable |
| @IsUniversallyUnique | States the scope of uniqueness for the ID |
| @isMaintainable | Fixed value = “true” [specifies object base] |
| @versionDate | Date/Time of version change |
| @externalReferenceDefaultURI | Indicates that the content is available for reuse by reference |
| @isPublished | Indicates that the contents are persistent and can be referenced by external documents |
| @xml:lang | The language of the metadata in the Maintainable object (Payload) |