SDMX Maintenance Agency
Maintenance Agency Structure
The “Agency” mechanism adopted by SDMX is hierarchical. At the top of the hierarchy is the SDMX Secretariat Agency Scheme. This contains the “top level” Agencies. An Agency in this Agency Scheme can also create and maintain its own Agency Scheme. Any organisation in this “second-level” scheme can also create its own Agency Scheme and so on. In this way the agencies in SDMX can be “federated” and this federation can reflect organisational and community structures. Furthermore, the unique identification of any SDMX structural metadata comprises a concatenation of the agency identifiers starting with the entry in the “top level” scheme and working down through the lower level schemes. This is shown diagrammatically below.
Agency SDMX has the Id of "SDMX" (although not shown in the diagram SDMX is in the "top-level" scheme maintained by the SDMX Secretariat)
Agency AA has the Id of “AA”
Agency CC in the Agency Scheme of AA has the Id of “AA.CC”
Agency CC in the Agency Scheme of BB has the Id of “BB.CC”
Agency EE in the Agency Scheme of DD in the Agency scheme of AA has the Id of “AA.DD.EE”
How the SDMX Identification Scheme Works
Each structural construct has a unique identifier. Essentially, the identifier is composed of four basic elements:
Object Type: this could be a maintained construct such as a Code List or a construct that is contained in a maintained construct such as a Code. For a construct that is contained in a maintained construct it is necessary to identify both constructs. For example the unique identity of the Code would need to identify also the Code List.
Maintenance Agency: for the maintained construct
Object Id: The identity of the construct, including the identity of the maintained construct (e.g. Code List) if the construct (e.g. Code) is contained
Version: of the maintained construct
The concatenation of these identifiers gives a unique identity to each structural object. The SDMX standard has a way of representing these identifiers as shown in the examples below.
Code List CL_FREQ version 1.0 maintained by SDMX:
Code A in Code List CL_FREQ version 1.0 maintained by SDMX:
In order to be completely unique it is necessary to also identify that the identification system is the SDMX system. The SDMX standard uses the URN (Uniform Resource Number) mechanism of the internet for its unique identifiers. The complete identifiers for the examples above are:
A URN for a Dimension in a DSD the identifier may look something like:
Note that the Global Registry constructs these URNs automatically from the individual Identifiers of the construct. The Global Registry will ignore any URNs that are submitted in an SDMX-ML message, except those that are used to reference other constructs.
How to Set Up a Sub Agency
An Agency in an Agency Scheme can set up a sub agency scheme.
Shown below is the Registry representation of the Agencies in the AA hierarchy.
The various agency schemes of these agencies are shown below.
Create a Sub Agency Scheme
Select the Agency BB from the list.
You will note that the Id of the scheme is fixed at AGENCIES and the version is fixed at 1.0.
Fill in the details and Save.
Add the DD Agency in the same way.
Finally Commit the Agency Scheme to the Registry
The Agency list now contains the new Agencies.
Creating SDMX Structures for an Agency
Select the Agency and the Type of Structure
Fill in the details and commit to the Registry.
Add the codes.
Note that the unique Id of any SDMX structure is shown in the URN
For a fuller explanation of how to create structural metadata see Global Registry Technical GUI