Wiki source code of SDMX STANDARDS: SECTION 5

Version 21.7 by Helena on 2025/05/15 14:18

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21.2	1	{{box title="Contents"}}
	2	{{toc/}}
	3	{{/box}}
2.1	4
21.2	5	= Revision History =
2.1	6
	7	(((
21.2	8	(% style="width:838.294px" %)
	9	\|(% style="width:188px" %)Revision\|(% style="width:205px" %)Date\|(% style="width:441px" %)Contents
	10	\|(% style="width:188px" %)DRAFT 1.0\|(% style="width:205px" %)May 2021\|(% style="width:441px" %)Draft release updated for SDMX 3.0 for public consultation
	11	\|(% style="width:188px" %)1.0\|(% style="width:205px" %)October 2021\|(% style="width:441px" %)Public release for SDMX 3.0
2.1	12	)))
	13
21.3	14	= 1 Introduction =
2.1	15
	16	The business vision for SDMX envisages the promotion of a “data sharing” model to facilitate low-cost, high-quality statistical data and metadata exchange. Data sharing reduces the reporting burden of organisations by allowing them to publish data once and let their counterparties “pull” data and related metadata as required. The scenario is based on:
	17
	18	* the availability of an abstract information model capable of supporting time series and cross-sectional data, structural metadata, and reference metadata (SDMX-IM)
	19	* standardised XML and JSON schemas for the SDMX-ML and SDMX-JSON formats derived from the model (XSD, JSON)
	20	* the use of web-services technology (XML, JSON, Open API)
	21
	22	Such an architecture needs to be well organised, and the SDMX Registry/Repository (SDMXRR) is tasked with providing structure, organisation, and maintenance and query interfaces for most of the SDMX components required to support the data sharing vision.
	23
	24	However, it is important to emphasise that the SDMX-RR provides support for the submission and retrieval of all SDMX structural metadata and provisioning metadata. Therefore, the Registry not only supports the data-sharing scenario, but this metadata is also vital in order to provide support for data and metadata reporting/collection, and dissemination scenarios.
	25
	26	Standard formats for the exchange of aggregated statistical data and metadata as prescribed in SDMX v3.0 are envisaged to bring benefits to the statistical community because data reporting and dissemination processes can be made more efficient.
	27
	28	As organisations migrate to SDMX enabled systems, many XML, JSON (and conventional) artefacts will be produced (e.g., Data Structure, Metadata Structure, Code List and Concept definitions – often collectively called structural metadata – XML schemas generated from data structure definitions, XSLT stylesheets for transformation and display of data and metadata, terminology references, etc.). The SDMX model supports interoperability, and it is important to be able to discover and share these artefacts between parties in a controlled and organized way.
	29
	30	This is the role of the registry.
	31
	32	With the fundamental SDMX standards in place, a set of architectural standards are needed to address some of the processes involved in statistical data and metadata exchange, with an emphasis on maintenance, retrieval and sharing of the structural metadata. In addition, the architectural standards support the registration and discovery of data and referential metadata.
	33
	34	These architectural standards address the ‘how’, rather than the ‘what’, and are aimed at enabling existing SDMX standards to achieve their mission. The architectural standards address registry services, which initially comprise:
	35
21.3	36	* structural metadata repository
	37	* data and metadata registration
	38	* query
2.1	39
	40	The registry services outlined in this specification are designed to help the SDMX community manage the proliferation of SDMX assets and to support data sharing for reporting and dissemination.
	41
	42	= {{id name="_Toc93832"/}}2 Scope and Normative Status =
	43
	44	The scope of this document is to specify the logical interfaces for the SDMX registry in terms of the functions required and the data that may be present in the function call, and the behaviour expected of the registry.
	45
	46	In this document, functions and behaviours of the Registry Interfaces are described in four ways:
	47
	48	* in text
	49	* with tables
	50	* with UML diagrams excerpted from the SDMX Information Model (SDMX-IM)
	51	* with UML diagrams that are not a part of the SDMX-IM but are included here for clarity and to aid implementations (these diagrams are clearly marked as “Logical Class Diagram ...”)
	52
	53	Whilst the introductory section contains some information on the role of the registry, it is assumed that the reader is familiar with the uses of a registry in providing shared metadata across a community of counterparties.
	54
	55	Note that chapters 5 and 6 below contain normative rules regarding the Registry Interface and the identification of registry objects. Further, the minimum standard for access to the registry is via a REST interface (HTTP or HTTPS), as described in the appropriate sections. The notification mechanism must support e-mail and HTTP/HTTPS protocols as described. Normative registry interfaces are specified in the SDMX-ML specification (Section 3 of the SDMX Standard). All other sections of this document are informative.
	56
	57	Note that although the term “authorised user” is used in this document, the SDMX standards do not define an access control mechanism. Such a mechanism, if required, must be chosen and implemented by the registry software provider.
	58
	59	= {{id name="_Toc93833"/}}3 Scope of the SDMX Registry/Repository =
	60
	61	== {{id name="_Toc93834"/}}3.1 Objective ==
	62
	63	The objective of the SDMX registry/repository is, in broad terms, to allow organisations to publish statistical data and reference metadata in known formats such that interested third parties can discover these data and interpret them accurately and correctly. The mechanism for doing this is twofold:
	64
	65	1. To maintain and publish structural metadata that describes the structure and valid content of data and reference metadata sources such as databases, metadata repositories, data sets, metadata sets. This structural metadata enables software applications to understand and to interpret the data and reference metadata in these sources.
	66	1. To enable applications, organisations, and individuals to share and to discover data and reference metadata. This facilitates data and reference metadata dissemination by implementing the data sharing vision of SDMX.
	67
	68	== {{id name="_Toc93835"/}}3.2 Structural Metadata ==
	69
	70	Setting up structural metadata and the exchange context (referred to as “data provisioning”) involves the following steps for maintenance agencies:
	71
	72	* agreeing and creating a specification of the structure of the data (called a Data Structure Definition or DSD in this document but also known as “key family”), which defines the dimensions, measures and attributes of a dataset and their valid value set;
	73	* if required, defining a subset or view of a DSD which allows some restriction of content called a “dataflow definition”;
	74	* agreeing and creating a specification of the structure of reference metadata (Metadata Structure Definition) which defines the metadata attributes and their presentational arrangement in a Metadataset or as part of a Dataset, and their valid values and content;
	75	* if required, defining a subset or view of an MSD which allows some restriction of content called a “metadataflow”;
	76	* defining which subject matter domains (specified as a Category Scheme) are related to the Dataflow and Metadataflow to enable browsing;
	77	* defining one or more lists of Data and Metadata Providers;
	78	* defining which Data/Metadata Providers have agreed to publish a given Dataflow/Metadataflow – this is called a Provision Agreement or Metadata Provision Agreement, respectively.
	79
	80	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_28806f51.jpg\|\|height="539" width="443"]]
	81
21.3	82	(% class="wikigeneratedid" id="HFigure1:SchematicoftheBasicStructuralArtefactsintheSDMX-IM" %)
	83	Figure 1: Schematic of the Basic Structural Artefacts in the SDMX-IM
2.1	84
	85	Note that in Figure 1 (but also most of the relevant subsequent figures) terms that include both data and metadata have been used. For example:
	86
	87	* Structure Definition: refers to Data Structure Definition (DSD) and Metadata Structure Definition (MSD)
	88	* Flow: refers to Dataflow and Metadataflow
	89	* Provision Agreement: refers to Provision Agreement (for data) and Metadata Provision Agreement
	90	* Provider Scheme: refers to Data Provider Scheme and Metadata Provider Scheme
	91	* Provider: refers to Data Provider and Metadata Provider
	92
	93	In that context, the term “Metadata” refers to reference metadata.
	94
	95	== {{id name="_Toc93836"/}}3.3 Registration ==
	96
	97	Publishing the data and reference metadata involves the following steps for a Data/Metadata Provider:
	98
	99	* making the reference metadata and data available in SDMX-ML/JSON conformant data files or databases (which respond to an SDMX query with data). The data and reference metadata files or databases must be web accessible, and must conform to an agreed Dataflow or Metadataflow (Data Structure Definition or Metadata Structure Definition subset);
	100	* registering the existence of published reference metadata and data files or databases with one or more SDMX registries.
	101
	102	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_1edb9829.jpg\|\|height="407" width="553"]]
	103
	104	Figure 2: Schematic of Registered Data and Metadata Sources in the SDMX-IM
	105
	106	== {{id name="_Toc93837"/}}3.4 Notification ==
	107
	108	Notifying interested parties of newly published or re-published data, reference metadata or changes in structural metadata involves:
	109
21.4	110	* registry support of a subscription-based notification service which sends an email or notifies an HTTP address announcing all published data that meets the criteria contained in the subscription request.
2.1	111
	112	== {{id name="_Toc93838"/}}3.5 Discovery ==
	113
	114	Discovering published data and reference metadata involves interaction with the registry to fulfil the following logical steps that would be carried out by a user interacting with a service that itself interacts with the registry and an SDMX-enabled data or reference metadata resource:
	115
	116	* optionally browsing a subject matter domain category scheme to find Dataflows (and hence Data Structure Definitions) and Metadataflows which structure the type of data and/or reference metadata being sought;
	117	* build a query, in terms of the selected Data Structure Definition or Metadata Structure Definition, which specifies what data are required and submitting this to a service that can query an SDMX registry which will return a list of (URLs of) data and reference metadata files and databases which satisfy the query;
	118	* processing the query result set and retrieving data and/or reference metadata from the supplied URLs.
	119
	120	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_1f4779f4.jpg\|\|height="328" width="554"]]
	121
	122	Figure 3: Schematic of Data and Metadata Discovery and Query in the SDMX-IM
	123
	124	= {{id name="_Toc93839"/}}4 SDMX Registry/Repository Architecture =
	125
	126	== {{id name="_Toc93840"/}}4.1 Architectural Schematic ==
	127
	128	The architecture of the SDMX registry/repository is derived from the objectives stated above. It is a layered architecture that is founded by a structural metadata repository which supports a provisioning metadata repository which supports the registry services. These are all supported by the SDMX-ML schemas. Applications can be built on top of these services which support the reporting, storage, retrieval, and dissemination aspects of the statistical lifecycle as well as the maintenance of the structural metadata required to drive these applications.
	129
	130	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_99c4cc7e.jpg\|\|height="325" width="553"]]
	131
	132	Figure 4: Schematic of the Registry Content and Services
	133
	134	== {{id name="_Toc93841"/}}4.2 Structural Metadata Repository ==
	135
	136	The basic layer is that of a structural metadata service which supports the lifecycle of SDMX structural metadata artefacts such as Maintenance Agencies, Data Structure Definitions, Metadata Structure Definitions, Provision Agreements, Processes etc. This layer is supported by the Structure Submission and Query Service.
	137
	138	Note that the SDMX REST API supports all of the SDMX structural artefacts. The only structural artefacts that are not yet supported are:
	139
	140	* Registration of data and metadata sources
	141	* Subscription and Notification
	142
	143	As of the initial version of SDMX 3.0 no messages are defined to support these artefacts; hence, users may need to use SDMX 2.1 Registry Interface messages, instead.
	144
	145	== {{id name="_Toc93842"/}}4.3 Provisioning Metadata Repository ==
	146
	147	The function of this repository is to support the definition of the structural metadata that describes the various types of data-store which model SDMX-conformant databases or files, and to link to these data sources. These links can be specified for a data/metadata provider, for a specific data or metadata flow. In the SDMX model this is called the Provision or Metadata Provision Agreement.
	148
	149	This layer is supported by the Data and Metadata Registration Service.
	150
	151	= {{id name="_Toc93843"/}}5 Registry Interfaces and Services =
	152
	153	== {{id name="_Toc93844"/}}5.1 Registry Interfaces ==
	154
	155	The Registry Interfaces are:
	156
	157	* Notify Registry Event
	158	* Submit Subscription Request
	159	* Submit Subscription Response
	160	* Submit Registration Request
	161	* Submit Registration Response
	162	* Query Registration Request
	163	* Query Registration Response
	164	* Query Subscription Request
	165	* Query Subscription Response
	166
	167	The registry interfaces are invoked in one of two ways:
	168
21.5	169	1. The interface is the name of the root node of the SDMX-ML document
	170	1. The interface is invoked as a child element of the RegistryInterface message where the RegistryInterface is the root node of the SDMX-ML document.
2.1	171
	172	In addition to these interfaces the registry must support a mechanism for submitting and querying for structural metadata. This is detailed in sections 5.2.2 and 5.2.3.
	173
	174	All these interactions with the Registry – with the exception of NotifyRegistryEvent – are designed in pairs. The first document, the one which invokes the SDMX-RR interface, is a “Request” document. The message returned by the interface is a “Response” document.
	175
	176	It should be noted that all interactions are assumed to be synchronous, with the exception of Notify Registry Event. This document is sent by the SDMX-RR to all subscribers whenever an even occurs to which any users have subscribed. Thus, it does not conform to the requestresponse pattern, because it is inherently asynchronous.
	177
	178	== {{id name="_Toc93845"/}}5.2 Registry Services ==
	179
	180	=== {{id name="_Toc93846"/}}5.2.1 Introduction ===
	181
	182	The services described in this section do not imply that each is implemented as a discrete web service.
	183
	184	=== {{id name="_Toc93847"/}}5.2.2 Structure Submission Service ===
	185
	186	The registry must support a mechanism for submitting structural metadata. This mechanism can be the SDMX REST interface for structural metadata (this is defined in the corresponding GitHub project, dedicated to the SDMX REST API: __[[https:~~/~~/github.com/sdmx>>url:https://github.com/sdmx-twg/sdmx-rest]][[->>url:https://github.com/sdmx-twg/sdmx-rest]][[twg/sdmx>>url:https://github.com/sdmx-twg/sdmx-rest]][[->>url:https://github.com/sdmx-twg/sdmx-rest]][[rest>>url:https://github.com/sdmx-twg/sdmx-rest]]__[[)>>url:https://github.com/sdmx-twg/sdmx-rest]]. In order for the architecture to be scalable, the finest-grained piece of structural metadata that can be processed by the SDMX-RR is a MaintainableArtefact, with the exception of Item Schemes, where changes at an Item level is also possible (see next section on the SDMX Information Model).
	187
	188	=== {{id name="_Toc93848"/}}5.2.3 Structure Query Service ===
	189
	190	The registry must support a mechanism for querying for structural metadata. This mechanism can be the SDMX REST interface for structural metadata (this is defined in the corresponding GitHub project, dedicated to the SDMX REST API: __[[https:~~/~~/github.com/sdmx>>url:https://github.com/sdmx-twg/sdmx-rest]][[->>url:https://github.com/sdmx-twg/sdmx-rest]][[twg/sdmx>>url:https://github.com/sdmx-twg/sdmx-rest]][[->>url:https://github.com/sdmx-twg/sdmx-rest]][[rest>>url:https://github.com/sdmx-twg/sdmx-rest]]__ [[)>>url:https://github.com/sdmx-twg/sdmx-rest]]. The registry response to this query mechanism is the SDMX Structure message, which has as its root node:
	191
	192	* Structure
	193
	194	The SDMX structural artefacts that may be queried are:
	195
	196	* data flows and metadata flows
	197	* data structure definitions and metadata structure definitions
	198	* code lists
	199	* value lists
	200	* concept schemes
	201	* reporting taxonomies
	202	* provision agreements and metadata provision agreements
	203	* structure maps
	204	* representation map
	205	* organisation scheme map
	206	* concept scheme map
	207	* category scheme map
	208	* reporting taxonomy map
	209	* processes
	210	* hierarchies
	211	* constraints
	212	* category schemes
	213	* categorisations and categorised objects (examples are categorised data flows and metadata flows, data structure definitions, metadata structure definitions, provision agreements registered data sources and metadata sources)
	214	* organisation schemes (agency scheme, data provider scheme, data consumer scheme, organisation unit scheme)
	215
	216	Due to the VTL implementation the other structural metadata artefacts that may be queried are:
	217
	218	* Transformation schemes
	219	* Custom type schemes
	220	* Name personalisation schemes
	221	* VTL mapping schemes
	222	* Ruleset schemes
	223	* User defined operator schemes
	224
	225	=== {{id name="_Toc93849"/}}5.2.4 Data and Reference Metadata Registration Service ===
	226
	227	This service must implement the following Registry Interfaces:
	228
	229	* SubmitRegistrationRequest
	230	* SubmitRegistrationResponse
	231	* QueryRegistrationRequest
	232	* QueryRegistrationResponse
	233
	234	The Data and Metadata Registration Service allows SDMX conformant files and webaccessible databases containing published data and reference metadata to be registered in the SDMX Registry. The registration process MAY validate the content of the datasets or metadatasets, and MAY extract a concise representation of the contents in terms of concept values (e.g., values of the data attribute, dimension, metadata attribute), or entire keys, and storing this as a record in the registry to enable discovery of the original dataset or metadata-set. These are called Constraints in the SDMX-IM.
	235
	236	The Data and Metadata Registration Service MAY validate the following, subject to the access control mechanism implemented in the Registry:
	237
	238	* that the data/metadata provider is allowed to register the dataset or metadataset;
	239	* that the content of the dataset or metadataset meets the validation constraints. This is dependent upon such constraints being defined in the structural repository and which reference the relevant Dataflow, Metadataflow, Data Provider, Metadata Provider, Data Structure Definition, Metadata Structure Definition, Provision Agreement, Metadata Provision Agreement;
	240	* that a queryable data source exists – this would necessitate the registration service querying the service to determine its existence;
	241	* that a simple data source exists (i.e., a file accessible at a URL);
	242	* that the correct Data Structure Definition or Metadata Structure Definition is used by the registered data;
	243	* that the components (Dimensions, Attributes, Measures, Metadata Attributes, etc.) are consistent with the Data Structure Definition or Metadata Structure Definition;
	244	* that the valid representations of the concepts to which these components correspond conform to the definition in the Data Structure Definition or Metadata Structure Definition. The Registration has an action attribute which takes one of the following values:
	245
21.6	246	(% style="width:755.294px" %)
	247	\|(% style="width:187px" %)Action Attribute Value\|(% style="width:566px" %)Behaviour
	248	\|(% style="width:187px" %)Append\|(% style="width:566px" %)Add this registration to the registry
	249	\|(% style="width:187px" %)Replace\|(% style="width:566px" %)Replace the existing Registration with this Registration identified by the id in the Registration of the Submit Registration Request
	250	\|(% style="width:187px" %)Delete\|(% style="width:566px" %)Delete the existing Registration identified by the id in the Registration of the Submit Registration Request
2.1	251
	252	The Registration has three Boolean attributes which may be present to determine how an SDMX compliant dataset or metadataset indexing application must index the datasets or metadatasets upon registration. The indexing application behaviour is as follows:
	253
21.6	254	(% style="width:759.294px" %)
	255	\|(% style="width:191px" %)Boolean Attribute\|(% style="width:565px" %)Behaviour if Value is “true”
	256	\|(% style="width:191px" %)indexTimeSeries\|(% style="width:565px" %)A compliant indexing application must index all the time series keys (for a Dataset registration) or metadata target values (for a Metadataset registration)
	257	\|(% style="width:191px" %)indexDataSet\|(% style="width:565px" %)(((
	258	A compliant indexing application must index the range of actual (present) values for each dimension of the Dataset (for a Dataset registration) or the range of actual (present) values for each Metadata Attribute which takes an enumerated value.
2.1	259	Note that for data this requires much less storage than full key indexing, but this method cannot guarantee that a specific combination of Dimension values (the Key) is actually present in the Dataset
	260	)))
21.6	261	\|(% style="width:191px" %)indexReportingPeriod\|(% style="width:565px" %)A compliant indexing application must index the time period range(s) for which data are present in the Dataset. The validity period of the Metadatasets may also be indexed.
2.1	262
	263	=== {{id name="_Toc93850"/}}5.2.5 Data and Reference Metadata Discovery ===
	264
	265	The Data and Metadata Discovery Service implements the following Registry Interfaces:
	266
	267	* QueryRegistrationRequest
	268	* QueryRegistrationResponse
	269
	270	=== {{id name="_Toc93851"/}}5.2.6 Subscription and Notification ===
	271
	272	The Subscription and Notification Service implements the following Registry Interfaces:
	273
	274	* SubmitSubscriptionRequest
	275	* SubmitSubscriptionResponse
	276	* NotifyRegistryEvent
	277
	278	The data sharing paradigm relies upon the consumers of data and metadata being able to pull information from data providers’ dissemination systems. For this to work efficiently, a data consumer needs to know when to pull data, i.e., when something has changed in the registry (e.g., a dataset has been updated and re-registered). Additionally, SDMX systems may also want to know if a new Data Structure Definition, Code List or Metadata Structure Definition has been added. The Subscription and Notification Service comprises two parts: subscription management, and notification.
	279
	280	Subscription management involves a user submitting a subscription request which contains:
	281
	282	* a query or constraint expression in terms of a filter which defines the events for which the user is interested (e.g., new data for a specific dataflow, or for a domain category, or changes to a Data Structure Definition).
	283	* a list of URIs or endpoints to which an XML notification message can be sent. Supported endpoint types will be email (mailto~:) and HTTP POST (a normal http:~/~/ address);
	284	* request for a list of submitted subscriptions;
	285	* deletion of a subscription;
	286
	287	Notification requires that the structural metadata repository and the provisioning metadata repository monitor any event which is of interest to a user (the object of a subscription request query), and to issue an SDMX notification document to the endpoints specified in the relevant subscriptions.
	288
	289	=== {{id name="_Toc93852"/}}5.2.7 Registry Behaviour ===
	290
	291	The following table defines the behaviour of the SDMX Registry for the various Registry Interface messages. It should be noted, though, that as of SDMX 3.0, an extended versioning scheme newly including semantic versioning is foreseen for all Maintainable Artefacts. Moreover, while the old versioning scheme is allowed, given there is no more a "final" flag, there is no way guaranteeing the consistency across version of a Maintainable, unless semantic versioning is used.
	292
	293	Given the above, the behaviour described in the following table concerns either draft Artefacts using semantic versioning or any Artefacts using the old versioning scheme. Nevertheless, in the case of semantic versioning the registry must respect the versioning rules when performing the actions below. For example, it is not possible to replace a non-draft Artefact that follows semantic versioning, unless a newer version is introduced according to the semantic versioning rules. Furthermore, even when draft Artefacts are submitted, the registry has to verify semantic versioning is respected against the previous non-draft versions. It is worth noting that the rules for semantic versioning and replacing or maintaining semantically versioned Artefacts applies to externally shared Artefacts. This means that any system may internally perform any change within a version of an Artefact, until the latter is shared outside of that system or becomes public. Then (as also explained in the SDMX Standards Section 6 “Technical Notes”) the Artefacts must adhere to the Semantic Versioning rules.
	294
21.6	295	(% style="width:757.294px" %)
	296	\|(% style="width:188px" %)Interface\|(% style="width:542px" %)Behaviour
	297	\|(% style="width:188px" %)All\|(% style="width:542px" %)(((
2.1	298	1. If the action is set to “replace” (or a maintainable Artefact is PUT or POSTed) then the entire contents of the existing maintainable object in the Registry MUST be replaced by the object submitted.
	299	1. Cross referenced structures MUST exist in either the submitted document (in Structures or Structure Location) or in the registry to which the request is submitted.
	300	1. If the action is set to “delete” (or a maintainable Artefact is DELETEd) then the Registry MUST verify that the object can be deleted. In order to qualify for deletion, the object must:
	301
	302	a) Be a draft version.
	303	)))
21.6	304	\|(% style="width:188px" %)Interface\|(% style="width:542px" %)Behaviour
	305	\|(% style="width:188px" %) \|(% style="width:542px" %)(((
	306	b) Not be explicitly{{footnote}}With semantic versioning, it is allowed to reference a range of artefacts, e.g., a DSD referencing a Codelist with version 1.2.3+ means all patch versions greater than 1.2.3. This means that deleting 1.2.4-draft does not break integrity of the aforementioned DSD.{{/footnote}} referenced from any other object in the Registry.
2.1	307
	308	4) The semantic versioning rules in the SDMX documentation MUST be obeyed.
	309	)))
21.6	310	\|(% style="width:188px" %)Structure submission\|(% style="width:542px" %)Structures are submitted at the level of the Maintainable Artefact and the behaviour in “All” above is therefore at the level of the Maintainable Artefact.
	311	\|(% style="width:188px" %)SubmitRegistrationRequest\|(% style="width:542px" %)If the datasource is a file (simple datasource) then the file MAY be retrieved and indexed according to the Boolean attributes set in the Registration. For a queryable datasource the Registry MAY validate that the source exists and can accept an SDMX data query.
2.1	312
	313	= {{id name="_Toc93853"/}}6 Identification of SDMX Objects =
	314
	315	== {{id name="_Toc93854"/}}6.1 Identification, Versioning, and Maintenance ==
	316
	317	All major classes of the SDMX Information model inherit from one of:
	318
	319	* //IdentifiableArtefact// – this gives an object the ability to be uniquely identified (see following section on identification), to have a user-defined URI, and to have multi-lingual annotations.
	320	* //NameableArtefact// – this has all of the features of //IdentifiableArtefact// plus the ability to have a multi-lingual name and description.
	321	* //VersionableArtefact// – this has all of the above features plus a version number, according to the SDMX versioning rules in SDMX Standards Section 6 “Technical Notes”, paragraph “4.3 Versioning”, and a validity period.
	322	* //MaintainableArtefact// – this has all of the above features, plus registry and structure URIs, and an association to the maintenance organisation of the object.
	323
	324	=== {{id name="_Toc93855"/}}6.1.1 Identification, Naming, Versioning, and Maintenance Model ===
	325
	326	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_1683f36a.jpg\|\|height="688" width="587"]]
	327
	328	Figure 5: Class diagram of fundamental artefacts in the SDMX-IM
	329
	330	The table below shows the identification and related data attributes to be stored in a registry for objects that are one of:
	331
	332	* //Annotable//
	333	* //Identifiable//
	334	* //Nameable//
	335	* //Versionable//
	336	* //Maintainable//
	337
21.2	338	:
2.1	339
	340	(((
21.6	341	(% style="width:1052.29px" %)
	342	\|Object Type\|(% style="width:241px" %)Data Attributes\|(% style="width:156px" %)Status\|Data type\|(% style="width:457px" %)Notes
	343	\|(% rowspan="4" %)//Annotable//\|(% style="width:241px" %)AnnotationTitle\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)
	344	\|(% style="width:241px" %)AnnotationType\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)
	345	\|(% style="width:241px" %)AnnotationURN\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)
	346	\|(% style="width:241px" %)AnnotationText in the form of InternationalString\|(% style="width:156px" %)C\| \|(% style="width:457px" %)This can have languagespecific variants
	347	\|(% rowspan="4" %)//Identifiable//\|(% style="width:241px" %)All content as for //Annotable// plus\|(% style="width:156px" %) \| \|(% style="width:457px" %)
	348	\|(% style="width:241px" %)id\|(% style="width:156px" %)M\|string\|(% style="width:457px" %)
	349	\|(% style="width:241px" %)uri\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)
	350	\|(% style="width:241px" %)urn\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)Although the urn is computable and therefore may not be submitted or stored physically, the Registry must return the urn for each object, and must be able to service a query on an object referenced solely by its urn.
	351	\|(% rowspan="3" %)//Nameable//\|(% style="width:241px" %)All content as for //Identifiable// plus\|(% style="width:156px" %) \| \|(% style="width:457px" %)
	352	\|(% style="width:241px" %)Name in the form of InternationalString\|(% style="width:156px" %)M\|string\|(% style="width:457px" %)This can have language specific variants.
	353	\|(% style="width:241px" %)Description in the form of InternationalString\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)This can have language specific variants.
	354	\|(% rowspan="4" %)//Versionable//\|(% style="width:241px" %)All content as for //Identifiable// plus\|(% style="width:156px" %) \| \|(% style="width:457px" %)
	355	\|(% style="width:241px" %)version\|(% style="width:156px" %)M\|string\|(% style="width:457px" %)This is the version number according to SDMX versioning rules.
	356	\|(% style="width:241px" %)validFrom\|(% style="width:156px" %)C\|Date/time\|(% style="width:457px" %)
	357	\|(% style="width:241px" %)validTo\|(% style="width:156px" %)C\|Date/time\|(% style="width:457px" %)
	358	\|//Maintainable//\|(% style="width:241px" %)All content as for //Versionable// plus\|(% style="width:156px" %) \| \|(% style="width:457px" %)
	359	\| \|(% style="width:241px" %)isExternalReference\|(% style="width:156px" %)C\|boolean\|(% style="width:457px" %)Value of “true” indicates that the actual resource is held outside of this registry. The actual reference is given in the registry URI or the structureURL, each of which must return a valid SDMX-ML file.
	360	\| \|(% style="width:241px" %)serviceURL\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)The url of the service that can be queried for this resource.
	361	\| \|(% style="width:241px" %)structureURL\|(% style="width:156px" %)C\|string\|(% style="width:457px" %)The url of the resource.
	362	\| \|(% style="width:241px" %)(Maintenance) organisationId\|(% style="width:156px" %)M\|string\|(% style="width:457px" %)The object must be linked to a maintenance organisation, i.e., Agency or Metadata Provider.
2.1	363	)))
	364
	365	Table 1: Common Attributes of Object Types
	366
	367	=== {{id name="_Toc93856"/}}6.2 Unique identification of SDMX objects ===
	368
	369	===== {{id name="_Toc93857"/}}6.2.1 Agencies and Metadata Providers =====
	370
	371	The Maintenance Agency in SDMX is maintained in an Agency Scheme which itself is a sub class of Organisation Scheme – this is shown in the class diagram below.
	372
	373	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_c71516c5.jpg\|\|height="313" width="554"]]
	374
	375	Figure 6: Agency Scheme Model
	376
	377	The Agency in SDMX is extremely important. The Agency Id system used in SDMX is an nlevel structure. The top level of this structure is maintained by SDMX. Any Agency in this top level can declare sub agencies and any sub agency can also declare sub agencies. The Agency Scheme has a fixed id and version (version ‘1.0’) and is never declared explicitly in the SDMX object identification mechanism.
	378
	379	In order to achieve this SDMX adopts the following rules:
	380
	381	* Agencies are maintained in an Agency Scheme (which is a sub class of Organisation Scheme).
	382	* The agency of the Agency Scheme must also be declared in a (different) Agency Scheme.
	383	* The “top-level” agency is SDMX and maintains the “top-level” Agency Scheme.
	384	* Agencies registered in the top-level scheme can themselves maintain a single Agency Scheme. Agencies in these second-tier schemes can themselves maintain a single Agency Scheme and so on.
	385	* The AgencyScheme has a fixed version, i.e., ‘1.0’, hence it is an exception from the Semantic Versioning that other Artefacts follow.
	386	* There can be only one AgencyScheme maintained by any one Agency. It has a fixed id of AGENCIES.
	387	* The /hierarchy of Organisation is not inherited by Maintenance Agency – thus each Agency Scheme is a flat list of Maintenance Agencies.
	388	* The format of the agency identifier is agencyID.agencyID etc. The top-level agency in this identification mechanism is the agency registered in the SDMX agency scheme.
	389
	390	In other words, SDMX is not a part of the hierarchical ID structure for agencies. However, SDMX is, itself, a maintenance agency and is contained in the top-level Agency Scheme.
	391
	392	This supports a hierarchical structure of agencyID.
	393
	394	An example is shown below.
	395
	396	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_eaceb05e.jpg\|\|height="251" width="432"]]
	397
	398	Figure 7: Example of Hierarchic Structure of Agencies The following organizations maintain an Agency Scheme.
	399
	400	* SDMX – contains Agencies AA, BB
	401	* AA – contains Agencies CC, DD
	402	* BB – contains Agencies CC, DD
	403	* DD – Contains Agency EE
	404
	405	Each agency is identified by its full hierarchy excluding SDMX.
	406
	407	e.g., the id of EE as an agencyID is AA.DD.EE
	408
	409	An example of this is shown in the XML snippet below:
	410
21.7	411	[[image:1747307906944-697.png]]
2.1	412
	413	Figure 8: Example Showing Use of Agency Identifiers
	414
	415	Each of these maintenance agencies has an identical Code list with the Id CL_BOP. However, each is uniquely identified by means of the hierarchic agency structure.
	416
	417	Following the same principles, the Metadata Provider is the maintenance organisation for a special subset of Maintainable Artefacts, i.e., the Metadatasets; the latter are the containers of reference metadata combined with a target that those metadata refer to.
	418
21.6	419	=== {{id name="_Toc93858"/}}6.2.2 Universal Resource Name (URN) ===
2.1	420
21.6	421	==== 6.2.2.1 Introduction ====
2.1	422
	423	To provide interoperability between SDMX Registry/Repositories in a distributed network environment, it is important to have a scheme for uniquely identifying (and thus accessing) all first-class (Identifiable) SDMX-IM objects. Most of these unique identifiers are composite (containing maintenance agency, or parent object identifiers), and there is a need to be able to construct a unique reference as a single string. This is achieved by having a globally unique identifier called a universal resource name (URN) which is generated from the actual identification components in the SDMX-RR APIs. In other words, the URN for any Identifiable Artefact is constructed from its component identifiers (agency, id, version etc.).
	424
21.6	425	==== 6.2.2.2 URN Structure //__Case Rules for URN__ // ====
2.1	426
	427	For the URN, all parts of the string are case sensitive. The generic structure of the URN is as follows:
	428
	429	SDMXprefix.SDMX-IM-package-name.class-name=agencyid:maintainedobjectid(maintainedobject-version).*containerobject-id.object-id
	430
	431	~* this can repeat and may not be present (see explanation below)
	432
	433	Note that in the SDMX Information Model there are no concrete Versionable Artefacts that are not a Maintainable Artefact. For this reason, the only version information that is allowed is for the maintainable object.
	434
	435	The Maintenance agency identifier is separated from the maintainable artefact identifier by a colon ‘:’. All other identifiers in the SDMX URN syntax are separated by a period ‘.’. The version information is encapsulated in parentheses ‘()’ and adheres to the SDMX versioning rules, as explained in SDMX Standards Section 6 “Technical Notes”, paragraph “4.3 Versioning.
	436
21.7	437	==== 6.2.2.3 Explanation of the generic structure ====
2.1	438
	439	In the explanation below the actual object that is the target of the URN is called the actual object.
	440
	441	SDMXPrefix: urn:sdmx:org
	442
	443	SDMX-IM-package-name: sdmx.infomodel.package=
	444
	445	The packages are:
	446
	447	base codelist conceptscheme datastructure categoryscheme registry metadatastructure process structuremapping transformation
	448
	449	maintainable-object-id is the identifier of the maintainable object. This will always be present as all identifiable objects are either a maintainable object or contained in a maintainable object. maintainable-object-version is the version, according to the SDMX versioning rules, of the maintainable object and is enclosed in parentheses ‘()’, which are always present. container-object-id is the identifier of an intermediary object that contains the actual object which the URN is identifying. It is not mandatory as many actual objects do not have an intermediary container object. For instance, a Code is in a maintained object (Codelist) and has no intermediary container object, whereas a MetadataAttribute has an intermediary container object (MetadataAttributeDescriptor) and may have an intermediary container object, which is its parent MetadataAttribute. For this reason, the container object id may repeat, with each repetition identifying the object at the next-lower level in its hierarchy. Note that if there is only a single containing object in the model then it is NOT included in the URN structure. This applies to AttributeDescriptor, DimensionDescriptor, and MeasureDescriptor where there can be only one such object and this object has a fixed id. Therefore, whilst each of these has a URN, the id of the AttributeDescriptor, DimensionDescriptor, and MeasureDescriptor is not included when the actual object is a DataAttribute or a Dimension/ TimeDimension, or a Measure.
	450
	451	Note that although a Code can have a parent Code and a Concept can have a parent Concept these are maintained in a flat structure and therefore do not have a containerobject-id.
	452
	453	For example, the sequence is agency:DSDid(version).DimensionId and not agency:DSDid(version).DimensionDescriptorId.DimensionId.
	454
	455	object-id is the identifier of the actual object unless the actual object is a //Maintainable// object. If present it is always the last id and is not followed by any other character.
	456
	457	//__Generic Examples of the URN Structure__//
	458
	459	__Actual object is a maintainable__
	460
	461	SDMXPrefix.SDMX-IM-package-name.classname=agencyid:maintained-objectid(version)
	462
	463	__Actual object is contained in a maintained object with no intermediate containing object__
	464
	465	SDMXPrefix.SDMX-IM-package-name.classname=agencyid:maintained-objectid(version).object-id
	466
	467	__Actual object is contained in a maintained object with an intermediate containing object__
	468
	469	SDMXPrefix.SDMX-IM-package-name.classname=agencyid:maintained-objectid(version).contained-object-id.object-id
	470
	471	__Actual object is contained in a maintained object with no intermediate containing__ __object but__ __the object type itself is hierarchical__
	472
	473	In this case the object id may not be unique in itself but only within the context of the hierarchy. In the general syntax of the URN all intermediary objects in the structure (with the exception, of course, of the maintained object) are shown as a contained object. An example here would be a Category in a CategoryScheme. The Category is hierarchical, and all intermediate Categories are shown as a contained object. The example below shows the generic structure for CategoryScheme/ Category/ Category.
	474
	475	SDMXPrefix.SDMX-IM-package-name.classname=agencyid:maintained-objectid(version).contained-object-id.object-id
	476
	477	Actual object is contained in a maintained object with an intermediate containing object and the object type itself is hierarchical
	478
	479	In this case the generic syntax is the same as for the example above as the parent object is regarded as a containing object, even if it is of the same type. An example here is a MetadataAttribute where the contained objects are MetadataAttributeDescriptor (first contained object id) and MetadataAttribute (subsequent contained object ids). The example below shows the generic structure for MSD/ MetadataAttributeDescriptor/ MetadataAttribute/ MetadataAttribute
	480
	481	SDMXPrefix.SDMX-IM-package-name.classname=agencyid:maintained-objectid(version).contained-object-id.contained-object-id contained-objectid.object-id
	482
	483	//__Concrete Examples of the URN Structure__//
	484
	485	The Data Structure Definition CRED_EXT_DEBT of legacy version 2.1 maintained by the toplevel Agency TFFS would have the URN:
	486
	487	urn:sdmx:org.sdmx.infomodel.datastructure.DataStucture=TFFS:CRED_EXT_ DEBT(2.1)
	488
	489	The URN for a code for Argentina maintained by ISO in the code list CL_3166A2 of semantic version 1.0.0 would be:
	490
	491	urn:sdmx:org.sdmx.infomodel.codelist.Code=ISO:CL_3166A2(1.0.0).AR
	492
	493	The URN for a category (id of 1) which has parent category (id of 2) maintained by SDMX in the category scheme SUBJECT_MATTER_DOMAINS of the semantic extended version 1.0.0draft would be:
	494
	495	urn:sdmx:org.sdmx.infomodel.categoryscheme.Category=SDMX:SUBJECT_MATT ER_DOMAINS(1.0.0-draft).1.2
	496
	497	The URN for a Metadata Attribute maintained by SDMX in the MSD CONTACT_METADATA of semantic version 1.0.0 where the hierarchy of the Metadata Attribute is CONTACT_DETAILS/CONTACT_NAME would be:
	498
	499	urn:sdmx:org.sdmx.infomodel.metadatastructure.MetadataAttribute=SDMX: CONTACT_METADATA(1.0.0).CONTACT_DETAILS.CONTACT_NAME
	500
	501	The TFFS defines ABC as a sub-Agency of TFFS then the URN of a Dataflow maintained by ABC and identified as EXTERNAL_DEBT of semantic version 1.0.0 would be:
	502
	503	urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=TFFS.ABC:EXTERNAL_ DEBT(1.0.0)
	504
	505	The SDMX-RR MUST support this globally unique identification scheme. The SDMX-RR MUST be able to create the URN from the individual identification attributes submitted and to transform the URN to these identification attributes. The identification attributes are:
	506
	507	* Identifiable and Nameable Artefacts: id (in some cases this id may be hierarchic)
	508	* Maintainable Artefacts: id, version, agencyId
	509
	510	The SDMX-RR MUST be able to resolve the unique identifier of an SDMX artefact and to produce an SDMX-ML rendering of that artefact if it is located in the Registry.
	511
21.7	512	=== {{id name="_Toc93859"/}}6.2.3 Table of SDMX-IM Packages and Classes ===
2.1	513
	514	The table below lists all of the packages in the SDMX-IM together with the concrete classes that are in these packages and whose objects have a URN.
	515
21.7	516	(% style="width:651.294px" %)
	517	\|(% style="width:134px" %)Package\|(% style="width:502px" %)URN class name (model class name where this is different)
	518	\|(% style="width:134px" %)base\|(% style="width:502px" %)Agency
	519	\|(% style="width:134px" %) \|(% style="width:502px" %)AgencyScheme
	520	\|(% style="width:134px" %) \|(% style="width:502px" %)DataConsumer
	521	\|(% style="width:134px" %) \|(% style="width:502px" %)DataConsumerScheme
	522	\|(% style="width:134px" %) \|(% style="width:502px" %)DataProvider
	523	\|(% style="width:134px" %) \|(% style="width:502px" %)DataProviderScheme
	524	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataProvider
	525	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataProviderScheme
	526	\|(% style="width:134px" %) \|(% style="width:502px" %)OrganisationUnit
	527	\|(% style="width:134px" %) \|(% style="width:502px" %)OrganisationUnitScheme
	528	\|(% style="width:134px" %)datastructure\|(% style="width:502px" %)AttributeDescriptor
	529	\|(% style="width:134px" %) \|(% style="width:502px" %)DataAttribute
	530	\|(% style="width:134px" %) \|(% style="width:502px" %)Dataflow
	531	\|(% style="width:134px" %) \|(% style="width:502px" %)DataStructure (DataStructureDefinition)
	532	\|(% style="width:134px" %) \|(% style="width:502px" %)Dimension
	533	\|(% style="width:134px" %) \|(% style="width:502px" %)DimensionDescriptor
	534	\|(% style="width:134px" %) \|(% style="width:502px" %)GroupDimensionDescriptor
	535	\|(% style="width:134px" %) \|(% style="width:502px" %)Measure
	536	\|(% style="width:134px" %) \|(% style="width:502px" %)MeasureDescriptor
	537	\|(% style="width:134px" %) \|(% style="width:502px" %)TimeDimension
	538	\|(% style="width:134px" %) \|(% style="width:502px" %)
	539	\|(% style="width:134px" %)metadatastructure\|(% style="width:502px" %)MetadataAttribute
	540	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataAttributeDescriptor
	541	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataStructure MetadataStructureDefinition)
	542	\|(% style="width:134px" %) \|(% style="width:502px" %)Metadataflow
	543	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataSet
	544	\|(% style="width:134px" %) \|(% style="width:502px" %)
	545	\|(% style="width:134px" %)process\|(% style="width:502px" %)Process
	546	\|(% style="width:134px" %) \|(% style="width:502px" %)ProcessStep
	547	\|(% style="width:134px" %) \|(% style="width:502px" %)Transition
	548	\|(% style="width:134px" %) \|(% style="width:502px" %)
	549	\|(% style="width:134px" %)registry\|(% style="width:502px" %)DataConstraint
	550	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataConstraint
	551	\|(% style="width:134px" %) \|(% style="width:502px" %)MetadataProvisionAgreement
	552	\|(% style="width:134px" %) \|(% style="width:502px" %)ProvisionAgreement
	553	\|(% style="width:134px" %) \|(% style="width:502px" %)Subscription
	554	\|(% style="width:134px" %) \|(% style="width:502px" %)
	555	\|(% style="width:134px" %)structuremapping\|(% style="width:502px" %)CategorySchemeMap
	556	\|(% style="width:134px" %) \|(% style="width:502px" %)ConceptSchemeMap
	557	\|(% style="width:134px" %) \|(% style="width:502px" %)OrganisationSchemeMap
	558	\|(% style="width:134px" %) \|(% style="width:502px" %)ReportingTaxonomyMap
	559	\|(% style="width:134px" %) \|(% style="width:502px" %)RepresentationMap
	560	\|(% style="width:134px" %) \|(% style="width:502px" %)StructureMap
	561	\|(% style="width:134px" %) \|(% style="width:502px" %)
	562	\|(% style="width:134px" %)codelist\|(% style="width:502px" %)Code
	563	\|(% style="width:134px" %) \|(% style="width:502px" %)Codelist
	564	\|(% style="width:134px" %) \|(% style="width:502px" %)HierarchicalCode
	565	\|(% style="width:134px" %) \|(% style="width:502px" %)Hierarchy
	566	\|(% style="width:134px" %) \|(% style="width:502px" %)HierarchyAssociation
	567	\|(% style="width:134px" %) \|(% style="width:502px" %)Level
	568	\|(% style="width:134px" %) \|(% style="width:502px" %)ValueList
	569	\|(% style="width:134px" %) \|(% style="width:502px" %)
	570	\|(% style="width:134px" %)categoryscheme\|(% style="width:502px" %)Categorisation
	571	\|(% style="width:134px" %) \|(% style="width:502px" %)Category
	572	\|(% style="width:134px" %) \|(% style="width:502px" %)CategoryScheme
	573	\|(% style="width:134px" %) \|(% style="width:502px" %)ReportingCategory
	574	\|(% style="width:134px" %) \|(% style="width:502px" %)ReportingTaxonomy
	575	\|(% style="width:134px" %)conceptscheme\|(% style="width:502px" %)Concept
	576	\|(% style="width:134px" %) \|(% style="width:502px" %)ConceptScheme
	577	\|(% style="width:134px" %) \|(% style="width:502px" %)
	578	\|(% style="width:134px" %)transformation\|(% style="width:502px" %)CustomType
	579	\|(% style="width:134px" %) \|(% style="width:502px" %)CustomTypeScheme
	580	\|(% style="width:134px" %) \|(% style="width:502px" %)NamePersonalisation
	581	\|(% style="width:134px" %) \|(% style="width:502px" %)NamePersonalisationScheme
	582	\|(% style="width:134px" %) \|(% style="width:502px" %)Ruleset
	583	\|(% style="width:134px" %) \|(% style="width:502px" %)RulesetScheme
	584	\|(% style="width:134px" %) \|(% style="width:502px" %)Transformation
	585	\|(% style="width:134px" %) \|(% style="width:502px" %)TransformationScheme
	586	\|(% style="width:134px" %) \|(% style="width:502px" %)UserDefinedOperator
	587	\|(% style="width:134px" %) \|(% style="width:502px" %)UserDefinedOperatorScheme
	588	\|(% style="width:134px" %) \|(% style="width:502px" %)VtlCodelistMapping
	589	\|(% style="width:134px" %) \|(% style="width:502px" %)VtlConceptMapping
	590	\|(% style="width:134px" %) \|(% style="width:502px" %)VtlDataflowMapping
	591	\|(% style="width:134px" %) \|(% style="width:502px" %)VtlMappingScheme
2.1	592
	593	Table 2: SDMX-IM Packages and Contained Classes
	594
	595	=== {{id name="_Toc93860"/}}6.2.4 URN Identification components of SDMX objects ===
	596
	597	The table below describes the identification components for all SDMX object types that have identification. Note the actual attributes are all ‘id’ but have been prefixed by their class name or multiple class names to show navigation, e.g., ‘conceptSchemeAgencyId’ is really the ‘Id’ attribute of the Agency class that is associated to the ConceptScheme.
	598
	599	Note that for brevity the URN examples omit the prefix (classnames in italics indicate maintainable objects, keywords in bold indicate fixed value) All URNs have the prefix:
	600
	601	urn:sdmx.org.sdmx.infomodel.{package}.{classname}=
	602
	603	\|Classname\|Ending URN pattern\|Example
21.6	604	\|Agency^^[[(% class="wikiinternallink wikiinternallink wikiinternallink" %)^^2^^>>path:#sdfootnote2sym\|\|name="sdfootnote2anc"]](%%)^^\|agencySchemeAgencyId:AGENCIES(1.0).agencyId\|ECB:AGENCIES(1.0).AA
2.1	605	\|//AgencyScheme//\|agencySchemeAgencyId:AGENCIES(1.0)\|ECB:AGENCIES(1.0)
	606	\|//Categorisation//\|categorisationAgencyId:categorisationId(version)\|IMF:cat001(1.0.0)
	607	\|Category\|categorySchemeAgencyId:categorySchemeId(versi on).categoryId.categoryId.categoryId etc.\|IMF:SDDS(1.0.0):level_1_category.level_2_category …
	608	\|//CategoryScheme//\|categorySchemeAgencyId:categorySchemeId(versi on)\|IMF:SDDS(1.0.0)
	609
	610	\|Classname\|Ending URN pattern\|Example
	611	\|//CategorySchemeMap//\|(((
	612	catSchemeMapAgencyId:catSchemeMapId(version
	613
	614	)
	615	)))\|SDMX:EUROSTAT_SUBJECT_DOMAIN(1.0.0)
	616	\|Code\|codeListAgencyId:codelistId(version).codeId\|SDMX:CL_FREQ(1.0.0).Q
	617	\|//Codelist//\|codeListAgencyId:codeListId(version)\|SDMX:CL_FREQ(1.0.0)
	618	\|ComponentMap\|structureMapAgencyId:structureMap(version).com ponentMapId\|SDMX:BOP_STRUCTURES(1.0.0).REF_AREA_TO_COUNT RY
	619	\|Concept\|conceptSchemeAgencyId:conceptSchemeId(versio n).conceptId\|SDMX:CROSS_DOMAIN_CONCEPTS(1.0.0).FREQ
	620	\|//ConceptScheme//\|conceptSchemeAgencyId:conceptSchemeId(versio n)\|SDMX:CROSS_DOMAIN_CONCEPTS(1.0.0)
	621	\|//ConceptSchemeMap//\|(((
	622	conceptSchemeMapAgencyId:conceptSchemeMap
	623
	624	Id(version)
	625	)))\|SDMX:CONCEPT_MAP(1.0.0)
	626	\|CustomType\|customTypeSchemeAgencyId customTypeSchemeId(version) customTypeId\|ECB: CUSTOM_TYPE_SCHEME(1.0.0).CUSTOM_TYPE_1
	627	\|//CustomTypeScheme//\|customTypeSchemeAgencyId customTypeSchemeId(version)\|ECB:CUSTOM_TYPE_SCHEME(1.0.0)
	628	\|DataAttrribute\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).dataAttributeId\|TFFS:EXT_DEBT(1.0.0).OBS_STATUS
	629	\|//DataConstraint//\|dataConstraintAgencyId:dataConstraintId(version)\|TFFS:CREDITOR_DATA_CONTENT(1.0.0)
	630
	631	\|Classname\|Ending URN pattern\|Example
	632	\|DataConsumer\|dataConsumerSchemeAgencyId:DATA_CONSUME RS(1.0).dataConsumerId\|SDMX:DATA_CONSUMERS(1.0).CONSUMER_1
	633	\|//DataConsumerScheme//\|(((
	634	dataConsumerSchemeAgencyId:DATA_CONSUME
	635
	636	RS(1.0)
	637	)))\|SDMX:DATA_CONSUMERS(1.0)
	638	\|//Dataflow//\|dataflowAgencyId:dataflowId(version)\|TFFS:CRED_EXT_DEBT(1.0.0)
	639	\|DataProvider\|(((
	640	dataProviderSchemeAgencyId:DATA_PROVIDERS(
	641
	642	1.0).dataProviderId
	643	)))\|SDMX:DATA_PROVIDERS(1.0).PROVIDER_1
	644	\|//DataProviderScheme//\|(((
	645	dataProviderSchemeAgencyId:DATA_PROVIDERS(
	646
	647	1.0)
	648	)))\|SDMX:DATA_PROVIDERS(1.0)
	649	\|//DataStructure//\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version)\|TFFS:EXT_DEBT(1.0.0)
	650	\|Dimension\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).dimensionId\|TFFS:EXT_DEBT(1.0.0).FREQ
	651	\|(((
	652	DimensionDescriptor
	653
	654	MeasureDescriptor
	655
	656	AttributeDescriptor
	657	)))\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).componentListId where the componentListId is the name of the class (there is only one occurrence of each in the Data Structure Definition)\|(((
	658	TFFS:EXT_DEBT(1.0.0).DimensionDescriptor
	659
	660	TFFS:EXT_DEBT(1.0.0).MeasureDescriptor
	661
	662	TFFS:EXT_DEBT(1.0.0).AttributeDescriptor
	663	)))
	664	\|GroupDimensionDescriptor\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).groupDimensionDescriptorId\|TFFS:EXT_DEBT(1.0.0).SIBLING
	665	\|HierarchicalCode\|hierarchyAgencyId:hierarchyId(version).hierarchica lCode.hierarchicalCode\|UNESCO:H-C-GOV(1.0.0).GOV_CODE1.GOV_CODE1_1
	666
	667	\|Classname\|Ending URN pattern\|Example
	668	\|//Hierarchy//\|hierarchyAgencyId:hierarchyId(version)\|UNESCO:H-C-GOV(1.0.0)
	669	\|//HierarchyAssociation//\|hierarchyAssociationAgencyId:hierarchyAssociatio nId(version)\|UNESCO:CL_EXP_SOURCE(1.0.0)
	670	\|Level\|hierarchyAgencyId:hierarchyId(version).level\|UNESCO:H-C-GOV(1.0.0).LVL1
	671	\|Measure\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).measureId\|TFFS:EXT_DEBT(1.0.0).OBS_VALUE
	672	\|MetadataAttribute\|(((
	673	msdAgencyId:msdId(version).metadataAttributeId.
	674
	675	metadataAttributeId
	676	)))\|IMF:SDDS_MSD(1.0.0).COMPILATION.METHOD
	677	\|MetadataAttributeDescriptor\|msdAgencyId:msdId(version).metadataAttributeDe scriptorId\|IMF:SDDS_MSD(1.0.0).MetadataAttributeDescriptor
	678	\|//MetadataConstraint//\|metadataConstraintAgencyId:metadataConstraintI d(version)\|TFFS:CREDITOR_METADATA_CONTENT(1.0.0)
	679	\|//Metadataflow//\|metadataflowAgencyId:metadataflowId(version)\|IMF:SDDS_MDF(1.0.0)
	680	\|MetadataProvider\|metadataProviderSchemeAgencyId:METADATA_P ROVIDERS(1.0).metadataProviderId\|SDMX:METADATA_PROVIDERS(1.0).MD_PROVIDER_1
	681	\|//MetadataProviderScheme//\|metadataProviderSchemeAgencyId:METADATA_P ROVIDERS(1.0)\|SDMX:METADATA_PROVIDERS(1.0)
	682	\|//MetadataProvisionAgreement//\|metadataProvisionAgreementAgencyId:metadataP rovisionAgreementId(version)\|IMF:SDDS_MDF_AB(1.0.0)
	683	\|//MetadataSet//\|metadataProviderId:metadataSetId(version)\|MD_PROVIDER:METADATASET(1.0.0)
	684	\|//MetadataStructure//\|msdAgencyId:msdId(version)\|IMF:SDDS_MSD(1.0.0)
	685
	686	\|Classname\|Ending URN pattern\|Example
	687	\|NamePersonalisation\|namePersonalisationSchemeAgencyId namePersonalisationSchemeId(version) namePersonalisationId\|ECB:PSN_SCHEME(1.0.0).PSN1234
	688	\|//NamePersonalisationScheme//\|namePersonalisationSchemeAgencyId namePersonalisationSchemeId(version)\|ECB:PSN_SCHEME(1.0.0)
	689	\|//OrganisationSchemeMap//\|orgSchemeMapAgencyId:orgSchemeMapId(versio n)\|SDMX:AGENCIES_PROVIDERS(1.0.0)
	690	\|OrganisationUnit\|organisationUnitSchemeAgencyId:organisationUni tSchemeId(version).organisationUnitId\|ECB:ORGANISATIONS(1.0.0).1F
	691	\|//OrganisationUnitScheme//\|organisationUnitSchemeAgencyId:organisationUni tSchemeId(version)\|ECB:ORGANISATIONS(1.0.0)
	692	\|//Process//\|processAgencyId:processId{version)\|BIS:PROCESS1(1.0.0)
	693	\|ProcessStep\|(((
	694	processAgencyId:processId(version).processStepId.
	695
	696	processStepId
	697	)))\|BIS:PROCESS1(1.0.0).STEP1.STEP1_1
	698	\|//ProvisionAgreement//\|provisionAgreementAgencyId:provisionAgreement Id(version)\|TFFS:CRED_EXT_DEBT_AB(1.0.0)
	699	\|ReportingCategory\|(((
	700	reportingTaxonomyAgencyId:
	701
	702	reportingTaxonomyId(version).reportingCategoryI d.reportingCategoryId
	703	)))\|IMF:REP_1(1.0.0):LVL1_REP_CAT.LVL2_REP_CAT
	704	\|//ReportingTaxonomy//\|reportingTaxonomyAgencyId:reportingTaxonomyI d(version)\|IMF:REP_1(1.0.0)
	705	\|//ReportingTaxonomyMap//\|repTaxonomyAgencyId:repTaxonomyId(version)\|SDMX:RT_MAP(1.0.0)
	706
	707	\|Classname\|Ending URN pattern\|Example
	708	\|//RepresentationMap//\|repMapAgencyId:repMapId(version)\|SDMX:REF_AREA_MAPPING(1.0.0)
	709	\|Ruleset\|rulesetSchemeAgencyId rulesetSchemeId(version) rulesetId\|ECB:RULESET_23(1.0.0).SET111
	710	\|//RulesetScheme//\|rulesetSchemeAgencyId rulesetSchemeId(version)\|ECB:RULESET_23(1.0.0)
	711	\|//StructureMap//\|structureMapAgencyId:structureMap(version)\|SDMX:BOP_STRUCTURES(1.0.0)
	712	\|Subscription\|(((
	713	The Subscription is not itself an Identifiable Artefact and therefore it does not follow the rules for URN structure.
	714
	715	The name of the URN is registryURN There is no pre-determined format.
	716	)))\|This cannot be generated by a common mechanism as subscriptions, although maintainable in the sense that they can be submitted and deleted, are not mandated to be created by a maintenance agency and have no versioning mechanism. It is therefore the responsibility of the target registry to generate a unique Id for the Subscription, and for the application creating the subscription to store the registry URN that is returned from the registry in the subscription response message.
	717	\|TimeDimension\|dataStructureDefinitionAgencyId:dataStructureDef initionId(version).timeDimensionId\|TFFS:EXT_DEBT(1.0.0).TIME_PERIOD
	718	\|Transformation\|transformationSchemeAgencyId transformationSchemeId(version) transformationId\|ECB:TRANSFORMATION_SCHEME(1.0.0).TRANS_1
	719	\|//TransformationScheme//\|transformationSchemeAgencyId transformationSchemeId(version)\|ECB: TRANSFORMATION_SCHEME(1.0.0)
	720	\|Classname\|Ending URN pattern\|Example
	721	\|Transition\|(((
	722	processAgencyId:processId(version).processStepId.
	723
	724	transitionId
	725	)))\|BIS:PROCESS1(1.0.0).STEP1.TRANSITION1
	726	\|UserDefinedOperator\|userDefinedOperatorSchemeAgencyId userDefinedOperatorSchemeId(version) usserDefinedOperatorId\|ECB:OS_CALC(1.2.0).OS267
	727	\|//UserDefinedOperatorScheme//\|userDefinedOperatorSchemeAgencyId userDefinedOperatorSchemeId(version)\|ECB:OS_CALC(1.2.0)
	728	\|//ValueList//\|valuelistAgencyId:valuelistId(version)\|SDMX:VLIST(1.0.0)
	729	\|VtlCodelistMapping\|vtlMappingSchemeAgencyId vtlMappingSchemeId(version) vtlCodelistMappingId\|ECB:CLIST_MP(2.0.0).ABZ
	730	\|VtlConceptMapping\|vtlMappingSchemeAgencyId vtlMappingSchemeId(version) vtlConceptMappingId\|ECB:CLIST_MP(1.0.0).XYA
	731	\|VtlDataflowMapping\|vtlMappingSchemeAgencyId vtlMappingSchemeId(version) vtlDataflowMappingId\|ECB:CLIST_MP(1.0.0).MOQ
	732	\|//VtlMappingScheme//\|vtlMappingSchemeAgencyId VtlMappingSchemeId(version)\|ECB:CLIST_MP(2.0.0)
	733
	734	Table 3: Table of identification components for SDMX Identifiable Artefacts
	735
	736	= {{id name="_Toc93861"/}}7 Implementation Notes =
	737
	738	=== {{id name="_Toc93862"/}}7.1 Structural Definition Metadata ===
	739
	740	===== {{id name="_Toc93863"/}}7.1.1 Introduction =====
	741
	742	The SDMX Registry must have the ability to support agencies in their role of defining and disseminating structural metadata artefacts. These artefacts include data structure definitions, code lists, concepts etc. and are fully defined in the SDMX-IM. An authenticated agency may submit valid structural metadata definitions which must be stored in the registry. Note that the term “structural metadata” refers as a general term to all structural components (Data Structure Definitions, Metadata Structure Definitions, Code Lists, Concept Schemes, etc.)
	743
	744	At a minimum, structural metadata definitions may be submitted to and queried from the registry via an HTTP/HTTPS POST in the form of one of the SDMX-ML messages for structural metadata and the SDMX RESTful API for structure queries. The message may contain all structural metadata items for the whole registry, structural metadata items for one maintenance agency, or individual structural metadata items.
	745
	746	Structural metadata items
	747
	748	* may only be modified by the maintenance agency which created them;
	749	* may only be deleted by the agency which created them;
	750	* may not be deleted if they are referenced from other constructs in the Registry.
	751
	752	The level of granularity for the maintenance of SDMX Structural Metadata objects in the registry is the Maintainable Artefact. Especially for Item Schemes, though, partial maintenance may be performed, i.e., at the level of the Item, by submitting an Item Scheme with the 'isPartial' flag set and a reduced set of Items.
	753
	754	The following table lists the Maintainable Artefacts.
	755
	756	\|(% colspan="2" %)Maintainable Artefacts\|Content
21.2	757	\|Abstract Class\|Concrete Class\|
2.1	758	\|Item Scheme\|Codelist\|Code
21.2	759	\| \|Concept Scheme\|Concept
	760	\| \|Category Scheme\|Category
	761	\| \|Organisation Unit Scheme\|Organisation Unit
	762	\| \|Agency Scheme\|Agency
	763	\| \|Data Provider Scheme\|Data Provider
	764	\| \|Metadata Provider Scheme\|Metadata Provider
	765	\| \|Data Consumer Scheme\|Data Consumer
	766	\| \|Reporting Taxonomy\|Reporting Category
	767	\| \|Transformation Scheme\|Transformation
	768	\| \|Custom Type Scheme\|Custom Type
	769	\| \|Name Personalisation Scheme\|Name Personalisation
	770	\| \|Vtl Mapping Scheme\|Vtl Codelist Mapping Vtl Concept Mapping
	771	\| \|Ruleset Scheme\|Ruleset
	772	\| \|User Defined Operator Scheme\|User Defined Operator
2.1	773	\|Enumerated List\|ValueList\|Value Item
	774	\|Structure\|Data Structure Definition\|(((
	775	Dimension Descriptor
	776
	777	Group Dimension Descriptor
	778
	779	Dimension
	780
	781	Time Dimension
	782
	783	Attribute Descriptor
	784
	785	Data Attribute
	786
	787	Measure Descriptor
	788
	789	Measure
	790	)))
21.2	791	\| \|Metadata Structure Definition\|Metadata Attribute Descriptor Metadata Attribute
	792	\|Structure Usage\|Dataflow\|
	793	\| \|Metadataflow\|
2.1	794	\|None\|Process\|Process Step
	795	\|None\|Structure Map\|(((
	796	Component Map
	797
	798	Epoch Map
	799
	800	Date Pattern Map
	801	)))
	802	\|None\|Representation Map\|Representation Mapping
	803	\|Item Scheme Map\|Organisation Scheme Map\|Item Map
21.2	804	\| \|Concept Scheme Map\|Item Map
	805	\| \|Category Scheme Map\|Item Map
	806	\| \|Reporting Taxonomy Map\|Item Map
	807	\|None\|Provision Agreement\|
	808	\|None\|Metadata Provision Agreement\|
2.1	809	\|None\|Hierarchy\|Hierarchical Code
21.2	810	\|None\|Hierarchy Association\|
	811	\|None\|Categorisation\|
2.1	812
	813	Table 4: Table of Maintainable Artefacts for Structural Definition Metadata
	814
	815	===== {{id name="_Toc93864"/}}7.1.2 Item Scheme, Structure =====
	816
	817	The artefacts included in the structural definitions are:
	818
	819	• All types of Item Scheme (Codelist, Concept Scheme, Category Scheme, Organisation Scheme, Agency Scheme, Data Provider Scheme, Metadata Provider Scheme, Data Consumer Scheme, Organisation Unit Scheme, Transformation Scheme, Name Personalisation Scheme, Custom Type Scheme, Vtl Mapping Scheme, Ruleset Scheme, User Defined Operator Scheme)
	820
21.6	821	• All types of Enumerated List (ValueList)^^[[(% class="wikiinternallink wikiinternallink wikiinternallink" %)^^3^^>>path:#sdfootnote3sym\|\|name="sdfootnote3anc"]](%%)^^
2.1	822
	823	• All types of Structure (Data Structure Definition, Metadata Structure Definition)
	824
	825	• All types of Structure Usage (Dataflow, Metadataflow)
	826
	827	===== {{id name="_Toc93865"/}}7.1.3 Structure Usage =====
	828
	829	7.1.3.1 Structure Usage: Basic Concepts
	830
	831	The Structure Usage defines, in its concrete classes of Dataflow and Metadataflow, which flows of data and metadata use which specific Structure, and importantly for the support of data and metadata discovery, the Structure Usage can be linked to one or more Category in one or more Category Scheme using the Categorisation mechanism. This gives the ability for an application to discover data and metadata by “drilling down” the Category Schemes.
	832
	833	7.1.3.2 Structure Usage Schematic
	834
	835	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_52097ab5.jpg\|\|height="246" width="438"]]
	836
	837	Figure 9: Schematic of Linking the Data and Metadata Flows to Categories and Structure Definitions
	838
	839	7.1.3.3 Structure Usage Model
	840
	841	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_302cc1a2.jpg\|\|height="548" width="578"]]
	842
	843	Figure 10: SDMX-IM of links from Structure Usage to Category
	844
	845	In addition to the maintenance of the Dataflow and the Metadataflow, the following links must be maintained in the registry:
	846
	847	* Dataflow to Data Structure Definition
	848	* Metadataflow to Metadata Structure Definition
	849
	850	The following links may be created by means of a Categorisation
	851
	852	* Categorisation to Dataflow and Category
	853	* Categorisation to Metadataflow and Category
	854
	855	=== {{id name="_Toc93866"/}}7.2 Data and Metadata Provisioning ===
	856
	857	===== {{id name="_Toc93867"/}}7.2.1 Provisioning Agreement: Basic concepts =====
	858
	859	Data/Metadata provisioning defines a framework in which the provision of different types of statistical data and metadata by various data/metadata providers can be specified and controlled. This framework is the basis on which the existence of data can be made known to the SDMX-enabled community and hence the basis on which data can subsequently be discovered. Such a framework can be used to regulate the data content to facilitate the building of intelligent applications. It can also be used to facilitate the processing implied by service level agreements, or other provisioning agreements in those scenarios that are based on legal directives. Additionally, quality and timeliness metadata can be supported by this framework which makes it practical to implement information supply chain monitoring.
	860
	861	Note that the term “data provisioning” here includes both the provisioning of data and metadata.
	862
	863	Although the Provision Agreement directly supports the data-sharing “pull” model, it is also useful in “push” exchanges (bilateral and gateway scenarios), or in a dissemination environment. It should be noted, too, that in any exchange scenario, the registry functions as a repository of structural metadata.
	864
	865	===== {{id name="_Toc93868"/}}7.2.2 Provisioning Agreement Model – pull use case =====
	866
	867	An organisation which publishes statistical data or reference metadata and wishes to make it available to an SDMX enabled community is called a Data Provider. In terms of the SDMX Information Model, the Data Provider is maintained in a Data Provider Scheme.
	868
	869	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_ec727775.jpg\|\|height="455" width="551"]]
	870
	871	Figure 11: SDMX-IM of the Data Provider
	872
	873	Note that the Data Provider does not inherit the hierarchy association. The diagram below shows a logical schematic of the data model classes required to maintain provision agreements.
	874
	875	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_4dc392d6.jpg\|\|height="299" width="533"]]
	876
	877	Figure 12: Schematic of the Provision Agreement
	878
	879	The diagram below is a logical representation of the data required in order to maintain Provision Agreements.
	880
	881	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_7b3d291a.jpg\|\|height="246" width="579"]]
	882
	883	Figure 13: Logical class diagram of the information contained in the Provision Agreement
	884
	885	A Provision Agreement is structural metadata. Each Provision Agreement must reference a Data Provider or Metadata Provider and a Dataflow or Metadataflow Definition. The Data/Metadata Provider and the Dataflow/Metadataflow must exist already in order to set up a Metadata Provision or Provision Agreement.
	886
	887	=== {{id name="_Toc93869"/}}7.3 Data and Metadata Constraints ===
	888
	889	===== {{id name="_Toc93870"/}}7.3.1 Data and Metadata Constraints: Basic Concepts =====
	890
	891	Constraints are, effectively, lists of the valid or actual content of data and metadata. Constraints can be used to specify a subset of the theoretical content of data set or metadata set which can be derived from the specification of the DSD or MSD. A Constraint can comprise a list of keys or a list of content (usually code values) of a specific component such as a dimension or attribute.
	892
	893	Constraints comprise the specification of subsets of key or attribute values that are contained in a data source, or is to be provided for a Dataflow or Metadataflow, or directly attached to a Data Structure Definition or Metadata Structure Definition. This is important metadata because, for example, the full range of possibilities which is implied by the Data Structure Definition (e.g., the complete set of valid keys is the Cartesian product of all the values in the code lists for each of the Dimensions) is often more than is actually present in any specific data source, or more than is intended to be supplied according to a specific Dataflow.
	894
	895	Often a Data Provider will not be able to provide data for all key combinations, either because the combination itself is not meaningful, or simply because the provider does not have the data for that combination. In this case the Data Provider could constrain the data source (at the level of the Provision Agreement or the Data Provider) by supplying metadata that defines the key combinations or cube regions that are available. This is done by means of a Constraint. The Constraint is also used to define a code list subset which is used to populate a partial code list.
	896
	897	Furthermore, it is often useful to define subsets or views of the Data Structure Definition which restrict values in some code lists, especially where many such subsets restrict the same Data Structure Definition. Such a view is called a Dataflow, and there can be one or more defined for any Data Structure Definition.
	898
	899	Whenever data is published or made available by a Data Provider, it must conform to a Dataflow (and hence to a Data Structure Definition). The Dataflow is thus a means of enabling content based processing.
	900
	901	In addition, Constraints can be extremely useful in a data visualisation system, such as dissemination of statistics on a website. In such a system a Cube Region can be used to specify the Dimension codes that actually exist in a data source (these can be used to build relevant selection tables), and the Key Set can be used to specify the keys that exist in a data source (these can be used to guide the user to select only those Dimension code values that will return data based on the Dimension values already selected).
	902
	903	=== {{id name="_Toc93871"/}}7.3.2 Data and Metadata Constraints: Schematic ===
	904
	905	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_d089184e.jpg\|\|height="326" width="580"]]
	906
	907	Figure 14: Schematic of the Constraint and the Artefacts that can be constrained
	908
	909	=== {{id name="_Toc93872"/}}7.3.3 Data and Metadata Constraints: Model ===
	910
	911	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_8a88db1c.jpg\|\|height="564" width="583"]]
	912
	913	Figure 15: Logical class diagram showing inheritance between and reference to constrainable artefacts
	914
	915	Logical class diagram showing inheritance between and reference to constrainable artefacts
	916
	917	The class diagram above shows that Data Provider, Metadata Provider, Dataflow, Metadataflow, Provision Agreement, Metadata Provision Agreement, Data Structure Definition, Metadata Structure Definition, Simple Datasource and REST Datasource (via the abstract Query Datasource) are all concrete sub-classes of Constrainable Artefact and can therefore have Constraints specified. Note that the actual Constraint as submitted is associated to the reference classes which inherit from ConstrainableRef: these are used to refer to the classes to which the Constraint applies.
	918
	919	The content of the Constraint can be found in the SDMX Information Model document.
	920
	921	== {{id name="_Toc93873"/}}7.4 Data and Metadata Registration ==
	922
	923	=== {{id name="_Toc93874"/}}7.4.1 Basic Concepts ===
	924
	925	A Data Provider has published a new dataset conforming to an existing Dataflow (and hence Data Structure Definition). This is implemented as either a web-accessible SDMXML file, or in a database which has a web-services interface capable of responding to an SDMX RESTful query with an SDMX-ML data stream.
	926
	927	The Data Provider wishes to make this new data available to one or more data collectors in a “pull” scenario, or to make the data available to data consumers. To do this, the Data Provider registers the new dataset with one or more SDMX conformant registries that have been configured with structural and provisioning metadata. In other words, the registry “knows” the Data Provider and “knows” what data flows the data provider has agreed to make available.
	928
	929	The same mechanism can be used to report or make available a metadata set.
	930
	931	SDMX-RR supports dataset and metadata set registration via the Registration Request, which can be created by the Data/Metadata Provider (giving the Data Provider maximum control). The registry responds to the registration request with a registration response which indicates if the registration was successful. In the event of an error, the error messages are returned as a registry exception within the response.
	932
	933	=== {{id name="_Toc93875"/}}7.4.2 The Registration Request ===
	934
	935	==== 7.4.2.1 Registration Request Schematic ====
	936
	937	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_5cb2f17b.jpg\|\|height="337" width="554"]]
	938
	939	Figure 16: Schematic of the Objects Concerned with Registration
	940
	941	==== 7.4.2.2 Registration Request Model ====
	942
	943	The following UML diagram shows the composition of the registration request. Each request is made up of one or more Registrations, one per dataset or metadata set to be registered. The Registration can optionally have information, which has been extracted from the Registration:
	944
	945	* validFrom
	946	* validTo
	947	* lastUpdated
	948
	949	The last updated date is useful during the discovery process to make sure the client knows which data is freshest.
	950
	951	The Registration has an action attribute which takes one of the following values:
	952
21.2	953	:
2.1	954
	955	(((
	956	\|Action Attribute Value\|Behaviour
	957	\|Append\|Add this Registration to the registry
	958	\|Replace\|(((
	959	Replace the existing Registration with identified by the id in the
	960
	961	Registration of the SubmitRegistrationRequest
	962	)))
	963	\|Delete\|Delete the existing Registration identified by the id in the Registration of the SubmitRegistrationRequest
	964	)))
	965
	966	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_bc1dcdec.jpg\|\|height="575" width="579"]]
	967
	968	Figure 17: Logical Class Diagram of Registration of Data and Metadata
	969
	970	The //QueryDatasource// is an abstract class that represents a data source, which can understand an API query (i.e., a RESTful query – RESTDatasource) and respond appropriately. Each data source inherits the dataURL from //Datasource//, and the //QueryDatasource// has an additional URL to locate the specification of the service (specURL) to describe how to access it. All other supported protocols are assumed to use the SimpleDatasource URL.
	971
	972	A SimpleDatasource is used to reference a physical SDMX-ML file that is available at a URL.
	973
	974	The RegistrationRequest has an action attribute which defines whether this is a new (append) or updated (replace) Registration, or that the Registration is to be deleted (delete). The id is only provided for the replace and delete actions, as the Registry will allocate the unique id of the (new) Registration.
	975
	976	The Registration includes attributes that state how a SimpleDatasource is to be indexed when registered. The Registry registration process must act as follows:
	977
	978	Information in the data or metadata set is extracted and placed in one or more //Constraint//s (see the //Constraint// model in the SDMX Information Model – Section 2 of the SDMX Standards). The information to be extracted is indicated by the Boolean values set on the ProvisionAgreement or MetadataProvisionAgreement as shown in the table below.
	979
21.2	980	:
2.1	981
	982	(((
	983	\|Indexing Required\|Registration Process Activity
	984	\|indexTimeSeries\|Extract all the series keys and create a KeySet(s) Constraint.
	985	\|indexDataSet\|Extract all the codes and other content of the Key value of the Series Key in a Data Set and create one or more Cube Regions containing Member Selections of Dimension Components of the Constraints model in the SDMX-IM, and the associated Selection Value.
	986	\|indexReportingPeriod\|(((
	987	This applies only to a registered __dataset__.
	988
	989	Extract the Reporting Begin and Reporting End from the Header of the Message containing the data set, and create a Reference Period constraint.
	990	)))
	991	\|Indexing Required\|Registration Process Activity
	992	\|indexAttributes\|(((
	993	Data Set
	994
	995	Extract the content of the Attribute Values in a Data Set and create one or more Cube Regions containing Member Selections of Data Attribute Components of the Constraints model in the
	996
	997	SDMXIM, and the associated Selection Value
	998
	999	Metadata Set
	1000
	1001	Indicate the presence of a Reported Attribute by creating one or more Cube Regions containing Member Selections of Metadata Attribute Components of the Constraints model in the SDMX-IM. Note that the content is not stored in the Selection Value.
	1002	)))
	1003	)))
	1004
	1005	Constraints that specify the contents of a //QueryDatasource// are submitted to the Registry via the structure submission service (i.e., the RESTful API).
	1006
	1007	The Registration must reference the ProvisionAgreement or MetadataProvisionAgreement to which it relates.
	1008
	1009	===== {{id name="_Toc93876"/}}7.4.3 Registration Response =====
	1010
	1011	After a registration request has been submitted to the registry, a response is returned to the submitter indicating success or failure. Given that a registration request can hold many Registrations, then there must be a registration status for each Registration. The SubmitRegistration class has a status field, which is either set to “Success”, “Warning” or “Failure”.
	1012
	1013	If the registration has succeeded, a Registration will be returned – this holds the Registry-allocated Id of the newly registered //Datasource// plus a //Datasource// holding the URL to access the dataset, metadataset, or query service.
	1014
	1015	The RegistrationResponse returns set of registration status (one for each registration submitted) in terms of a StatusMessage (this is common to all Registry responses) that indicates success or failure. In the event of registration failure, a set of MessageText are returned, giving the error messages that occurred during registration. It is entirely possible when registering a batch of datasets, that the response will contain some successful and some failed statuses. The logical model for the RegistrationResponse is shown below:
	1016
	1017	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_6c58dd9b.jpg\|\|height="371" width="579"]]
	1018
	1019	Figure 18: Logical class diagram showing the registration response
	1020
	1021	== {{id name="_Toc93877"/}}7.5 Subscription and Notification Service ==
	1022
	1023	The contents of the SDMX Registry/Repository will change regularly: new code lists and key families will be published and new datasets and metadata-sets will be registered. To obviate the need for users to repeatedly query the registry to see when new information is available, a mechanism is provided to allow users to be notified when these events happen.
	1024
	1025	A user can submit a subscription in the registry that defines which events are of interest, and either an email and/or an HTTP address to which a notification of qualifying events will be delivered. The subscription will be identified in the registry by a URN, which is returned to the user when the subscription is created. If the user wants to delete the subscription at a later point, the subscription URN is used as identification. Subscriptions have a validity period expressed as a date range (startDate, endDate) and the registry may delete any expired subscriptions, and will notify the subscriber on expiry.
	1026
	1027	When a registry/repository artefact is modified, any subscriptions which are observing the object are activated, and either an email or HTTP POST is instigated to report details of the changes to the user specified in the subscription. This is called a “notification”.
	1028
	1029	=== {{id name="_Toc93878"/}}7.5.1 Subscription Logical Class Diagram ===
	1030
	1031	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_979e4862.jpg\|\|height="680" width="587"]]
	1032
	1033	Figure 19: Logical Class Diagram of the Subscription
	1034
	1035	=== {{id name="_Toc93879"/}}7.5.2 Subscription Information ===
	1036
	1037	Regardless of the type of registry/repository events being observed, a subscription always contains:
	1038
	1039	1. A set of URIs describing the end-points to which notifications must be sent if the subscription is activated. The URIs can be either mailto~: or http: protocol. In the former case an email notification is sent; in the latter an HTTP POST notification is sent.
	1040	1. A user-defined identifier, which is returned in the response to the subscription request. This helps with asynchronous processing and is NOT stored in the Registry.
	1041	1. A validity period which defines both when the subscription becomes active and expires. The subscriber may be sent a notification on expiration of the subscription.
	1042	1. A selector which specifies which type of events are of interest. The set of event types is:
	1043
	1044	:
21.2	1045	::
2.1	1046
	1047	(((
	1048	\|Event Type\|Comment
	1049	\|STRUCTURAL_REPOSITORY_EVENTS\|Life-cycle changes to Maintainable Artefacts in the structural metadata repository.
	1050	\|DATA_REGISTRATION_EVENTS\|Whenever a published dataset is registered. This can be either a SDMXML data file or an SDMX conformant database.
	1051	\|METADATA_REGISTRATION_EVENTS\|Whenever a published metadataset is registered. This can be either a SDMXML reference metadata file or an SDMX conformant database.
	1052	\|ALL_EVENTS\|All events of the specified EventType
	1053	)))
	1054
	1055	=== {{id name="_Toc93880"/}}7.5.3 Wildcard Facility ===
	1056
	1057	Subscription notification supports wildcarded identifier components URNs, which are identifiers which have some or all of their component parts replaced by the wildcard character `*`. Identifier components comprise:
	1058
	1059	* agencyID
	1060	* id
	1061	* version
	1062
	1063	Examples of wildcarded identifier components for an identified object type of Codelist are shown below:
	1064
	1065	AgencyID = *
	1066
	1067	Id = *
	1068
	1069	Version = *
	1070
	1071	This subscribes to all Codelists of all versions for all agencies.
	1072
	1073	AgencyID = AGENCY1
	1074
	1075	Id = CODELIST1
	1076
	1077	Version = *
	1078
	1079	This subscribes to all versions of Codelist CODELIST1 maintained by the agency AGENCY1.
	1080
	1081	AgencyID = AGENCY1
	1082
	1083	Id = *
	1084
	1085	Version = *
	1086
	1087	This subscribes to all versions of all Codelist objects maintained by the agency AGENCY1.
	1088
	1089	AgencyID = *
	1090
	1091	Id = CODELIST1
	1092
	1093	Version = *
	1094
	1095	This subscribes to all versions of Codelist CODELIST1 maintained by any agency.
	1096
	1097	Note that if the subscription is to the latest stable version then this can be achieved by the + character, i.e.:
	1098
	1099	Version = +
	1100
	1101	A subscription to the latest version (whether stable, draft or non-versioned) can be achieved by the ~~ character, i.e.:
	1102
	1103	Version = ~~
	1104
	1105	A subscription to the latest stable version within major version 2 starting with version 2.3.1 can be achieved by adding the + character after the minor version number, i.e.:
	1106
	1107	Version = 2.3+.1
	1108
	1109	The complete SDMX versioning syntax can be found in the SDMX Standards Section 6 “Technical Notes”, paragraph “4.3 Versioning”.
	1110
	1111	=== {{id name="_Toc93881"/}}7.5.4 Structural Repository Events ===
	1112
	1113	Whenever a maintainable artefact (data structure definition, concept scheme, codelist, metadata structure definition, category scheme, etc.) is added to, deleted from, or modified in the structural metadata repository, a structural metadata event is triggered. Subscriptions may be set up to monitor all such events, or focus on specific artefacts such as a Data Structure Definition.
	1114
	1115	=== {{id name="_Toc93882"/}}7.5.5 Registration Events ===
	1116
	1117	Whenever a dataset or metadata-set is registered a registration event is created. A subscription may be observing all data or metadata registrations, or it may focus on specific registrations as shown in the table below:
	1118
21.2	1119	:
2.1	1120
	1121	(((
	1122	\|Selector\|Comment
	1123	\|DataProvider & MetadataProvider\|Any datasets or metadata sets registered by the specified data or metadata provider will activate the notification.
	1124	\|ProvisionAgreement & MetadataProvisionAgreement\|Any datasets or metadata sets registered for the agreement will activate the notification.
	1125	\|Dataflow & Metadataflow\|Any datasets or metadata sets registered for the specified dataflow (or metadataflow) will activate the notification.
	1126	\|DataStructureDefinition & MetadataStructureDefinition\|Any datasets or metadata sets registered for those dataflows (or metadataflows) that are based on the specified Data Structure Definition will activate the notification
	1127	\|Category\|Any datasets or metadata sets registered for those dataflows, metadataflows, provision agreements that are categorised by the category.
	1128	)))
	1129
	1130	The event will also capture the semantic of the registration: deletion or replacement of an existing registration or a new registration.
	1131
	1132	== {{id name="_Toc93883"/}}7.6 Notification ==
	1133
	1134	=== {{id name="_Toc93884"/}}7.6.1 Logical Class Diagram ===
	1135
	1136	[[image:SDMX 3-0-0 SECTION 5 FINAL-1.0_en_24ffc51b.jpg\|\|height="379" width="579"]]
	1137
	1138	Figure 20: Logical Class Diagram of the Notification
	1139
	1140	A notification is an XML document that is sent to a user via email or http POST whenever a subscription is activated. It is an asynchronous one-way message.
	1141
	1142	Regardless of the registry component that caused the event to be triggered, the following common information is in the message:
	1143
	1144	* Date and time that the event occurred
	1145	* The URN of the artefact that caused the event
	1146	* The URN of the Subscription that produced the notification
	1147	* Event Action: Add, Replace, or Delete.
	1148
	1149	Additionally, supplementary information may be contained in the notification as detailed below.
	1150
	1151	=== {{id name="_Toc93885"/}}7.6.2 Structural Event Component ===
	1152
	1153	The notification will contain the MaintainableArtefact that triggered the event in a form similar to the SDMX-ML structural message (using elements from that namespace).
	1154
	1155	=== {{id name="_Toc93886"/}}7.6.3 Registration Event Component ===
	1156
	1157	The notification will contain the Registration.
	1158
	1159	[[1>>path:#sdfootnote1anc\|\|name="sdfootnote1sym"]] With semantic versioning, it is allowed to reference a range of artefacts, e.g., a DSD referencing a Codelist with version 1.2.3+ means all patch versions greater than 1.2.3. This means that deleting 1.2.4draft does not break integrity of the aforementioned DSD.
	1160
	1161	[[2>>path:#sdfootnote2anc\|\|name="sdfootnote2sym"]] The identification of an Agency in the URN structure for the maintainable object is by means of the agencyId. The AgencyScheme is not identified as SDMX has a mechanism for identifying an Agency uniquely by its Id. Note that this Id may be hierarchical. For example, a sub-agency of IMF is referred like this:
	1162
	1163	IMF.SubAgency1
	1164
	1165	[[3>>path:#sdfootnote3anc\|\|name="sdfootnote3sym"]] Note that Codelist is also an EnumeratedList.
21.6	1166
	1167	{{putFootnotes/}}