Structure of the URN¶
Canonical URN¶
Each section of the Canonical URN is separated by a “:” (colon). Within the ID section the Maintainable ID and Object ID are separated by a “.” (dot).
urn:ddi:agency[.sub-agency]:ID:Version
If the scopeOfUniqueness equals “Agency” the ID is the ID of the object.
Example: Canonical URN with uniqueness scoped to the Agency.¶
Object V321 version 2 within the Minnesota Population Center (us.mpc)
Object V321 version 2 within the Minnesota Population Center, Project IPUMS (listed as a sub-agency within us.mpc)
If the scopeOfUniqueness equals “Maintainable” the ID of a non-Maintainable object is structured as follows:
Example: Canonical URN with uniqueness scoped to the Maintainable.¶
Variable V321 version 2 within VariableScheme VS1 at the Minnesota Population Center (us.mpc)
Variable V321 version 2 within VariableScheme VS1 at the Minnesota Population Center, Project IPUMS (listed as a sub-agency within us.mpc)
Deprecated URN¶
Each section of the Deprecated URN is separated by a “:” (colon).
If the object itself is Maintainable the information on the parent maintainable is not included:
urn:ddi:agency[.sub-agency]: ObjectType:ObjectID:ObjectVersion
If the scopeOfUniqueness equals “Agency” the ID is the ID of the object.
Example: Deprecated URN with uniqueness scoped to the Agency.¶
Object V321 version 2 within the Minnesota Population Center (us.mpc)
urn:ddi:us.mpc:Variable:V321:2
Object V321 version 2 within the Minnesota Population Center, Project IPUMS (listed as a sub-agency within us.mpc)
urn:ddi:us.mpc.ipums:Variable:V321:2
If the scopeOfUniqueness equals “Maintainable” the ID of a non-Maintainable object is structured as follows:
urn:ddi:agency[.subagency]:MaintainableObjectType:MaintainableID:ObjectType:ObjectID:ObjectVersion
Example: Deprecated URN with uniqueness scoped to the Maintainable.¶
Variable V321 version 2 within VariableScheme VS1 at the Minnesota Population Center (us.mpc)
urn:ddi:us.mpc:VariableScheme:VS1:Variable:V321:2
Variable V321 version 2 within VariableScheme VS1 at the Minnesota Population Center, Project IPUMS (listed as a sub-agency within us.mpc)