Wiki source code of SDMX STANDARDS

Version 19.5 by Helena on 2025/05/16 15:56

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7.2	1	{{box title="Contents"}}
	2	{{toc/}}
	3	{{/box}}
	4
2.1	5	Revision History
	6
7.5	7	(% style="width:738.039px" %)
	8	\|(% style="width:187px" %)Revision\|(% style="width:157px" %)Date\|(% style="width:390px" %)Contents
	9	\|(% style="width:187px" %)DRAFT 1.0\|(% style="width:157px" %)May 2021\|(% style="width:390px" %)Draft release updated for SDMX 3.0 for public consultation
	10	\|(% style="width:187px" %)1.0\|(% style="width:157px" %)October 2021\|(% style="width:390px" %)Public Release for SDMX 3.0
2.1	11
	12	= 1 Overview =
	13
19.2	14	[[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#2ecc71" %)version(%%) 3.0 introduces new features, improvements and changes to the Standard in the following key areas:
2.1	15
	16	Information Model
	17
19.2	18	* Simplification and improvement of the [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] model
2.1	19	* Support for microdata
	20	* Support for geospatial data
19.2	21	* Support for [[code list>>doc:xwiki:Glossary.Code list.WebHome]] extension and discriminated union of [[code>>doc:xwiki:Glossary.Code.WebHome]] lists
2.1	22	* Improvements to structure mapping
19.2	23	* Improvements to [[code>>doc:xwiki:Glossary.Code.WebHome]] [[hierarchies>>doc:xwiki:Glossary.Hierarchy.WebHome]] for data discovery
2.1	24	* Improvements to constraints
	25
	26	Versioning of Structural Metadata Artefacts
	27
19.2	28	* Adoption of the three-number semantic versioning standard for [[structural metadata>>doc:xwiki:Glossary.Structural metadata.WebHome]] [[artefacts>>doc:xwiki:Glossary.Artefact.WebHome]] ([[https:~~/~~/semver.org/>>https://semver.org/\|\|rel="noopener noreferrer" target="_blank"]])
2.1	29
	30	REST Web Services Application Programming Interface (API)
	31
	32	* Change to a single ‘structure’ resource for structure queries simplifying the REST API specification by reducing the number of resources to five
	33	* Improvements to data queries
19.2	34	* Improvements to [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] queries
	35	* Support for [[structural metadata>>doc:xwiki:Glossary.Structural metadata.WebHome]] maintenance using HTTP PUT, POST and DELETE verbs
2.1	36
	37	SOAP Web Services API
	38
19.2	39	* The SOAP web services API has been deprecated with (% style="color:#2ecc71" %)version(%%) 3.0 standardising on REST;
2.1	40
	41	XML, JSON, CSV and EDI Transmission formats
	42
19.2	43	* The [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]], [[SDMX-JSON>>doc:xwiki:Glossary.SDMX-JSON.WebHome]] and [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]]-CSV specifications have been extended and modified where needed to support the new features and changes such as [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] and microdata
	44	* Obsolete [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] data message variants including Generic, Compact, Utility and Cross-sectional have been deprecated standardising on Structure Specific Data as the sole XML format for data exchange
	45	* The [[SDMX-EDI>>doc:xwiki:Glossary.SDMX-EDI.WebHome]] transmission format for structures and data has been deprecated
	46	* The organisation of structures into ‘collections’ in [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:xwiki:Glossary.SDMX-JSON.WebHome]] structure messages has been flattened and simplified
	47	* The option to reference structures in [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:xwiki:Glossary.SDMX-JSON.WebHome]] messages using Agency, ID and (% style="color:#2ecc71" %)Version(%%) has been deprecated with URN now exclusively used for all non-local referencing purpose
2.1	48
	49	Breaking Changes
	50
19.2	51	Many of the changes made are ‘breaking’ meaning that, while conversion between (% style="color:#2ecc71" %)versions(%%) may be possible in certain circumstances, the 3.0 specification is not directly backwardly compatible with earlier (% style="color:#2ecc71" %)versions(%%) of the Standard.
2.1	52
	53	A summary of the main breaking changes is given in chapter 2.
	54
	55	Content of the Document
	56
19.2	57	The remainder of the document provides a summary of the main changes. More detailed information can be found the [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]] 3.0 Technical Specifications, in particular:
2.1	58
	59	* Section 2 – Information Model
	60	* Section 5 – Registry Specification
	61	* Section 6 – Technical Notes
19.2	62	* [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]]-TWG GitHub for the REST API and the XML, JSON and CSV formats
2.1	63
	64	= 2 Summary of Breaking Changes in 3.0 =
	65
19.3	66	(% style="color:#2ecc71" %)Version(%%) 3.0 introduces breaking changes into the web services API, transmission formats and information model. A summary is given in the table below.
2.1	67
11.1	68	== 2.1 Web Services API ==
2.1	69
7.4	70	(% style="width:948.039px" %)
	71	\|REST API\|(% style="width:818px" %)(((
2.1	72	The REST API is not backwardly compatible due to modifications to the URLs and query parameters resulting in breaking changes in four of the five main resources:
	73
	74	* Structure queries
	75	* Data queries
	76	* Metadata queries
	77	* Availability queries
	78
	79	Schema queries are backwardly compatible.
	80
	81	//Guidance for implementors//
	82
19.3	83	REST API implementors may provide partial backward compatibility by using web server URL rewriting rules to translate (% style="color:#2ecc71" %)version(%%) 2.1 structure queries to the 3.0 equivalent.
2.1	84
19.3	85	Implementors are also recommended to (% style="color:#2ecc71" %)version(%%) their API services providing users with an explicit choice of which (% style="color:#2ecc71" %)version(%%) to use.
2.1	86	)))
7.4	87	\|SOAP API\|(% style="width:818px" %)The SOAP API has been deprecated.
2.1	88
11.1	89	== 2.2 Transmission Formats ==
2.1	90
	91	(((
7.4	92	(% style="width:952.039px" %)
	93	\|(% style="width:130px" %)SDMX-ML\|(% style="width:820px" %)(((
2.1	94	The following legacy XML data messages have been deprecated:
	95
19.3	96	[[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] 1.0/2.0 Generic (time-series) data message
	97	[[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] 1.0/2.0 Compact (time-series) data message
	98	[[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] 1.0/2.0 Utility (time-series) data message
	99	[[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] 1.0/2.0 Cross-Sectional data message [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] 2.1 Generic data messages (for observations, time-series and cross-sectional data)
2.1	100
19.3	101	Structure Specific is the only data message option in (% style="color:#2ecc71" %)version(%%) 3.0 but is not backwardly compatible with (% style="color:#2ecc71" %)version(%%) 2.1 due to several changes including deprecation of the option to reference structures like the [[DSD>>doc:xwiki:Glossary.Data structure definition.WebHome]], [[Dataflow>>doc:xwiki:Glossary.Dataflow.WebHome]] and [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]] using their Agency, ID and (% style="color:#2ecc71" %)Version(%%). The time series variant of the message has also been deprecated.
2.1	102
19.3	103	The [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] structure message is not backwardly compatible primarily due to:
2.1	104
	105	* Changes to the information model
7.5	106	* Changes to the way the structures are organised into ‘collections’ within the message
19.3	107	* Deprecation of the Agency, ID, (% style="color:#2ecc71" %)Version(%%) option for referencing of structures in messages
2.1	108	)))
7.4	109	\|(% style="width:130px" %)SDMX-JSON\|(% style="width:820px" %)(((
19.3	110	The JSON data message is not backwardly compatible with (% style="color:#2ecc71" %)version(%%) 2.1 primarily due to changes needed to support the improved REST API data queries, in particular the ability to retrieve in one operation data from multiple [[datasets>>doc:xwiki:Glossary.Data set.WebHome]] with potentially different Data Structure Definitions.
2.1	111
	112	The JSON structure message is not backwardly compatible primarily due to:
	113
	114	* Changes to the information model
7.6	115	* Changes to the way the structures are organised into ‘collections’ within the message
19.3	116	* Deprecation of the Agency, ID, (% style="color:#2ecc71" %)Version(%%) option for referencing of structures in messages
2.1	117	)))
7.4	118	\|(% style="width:130px" %)SDMX-EDI\|(% style="width:820px" %)The EDI format for both structures and data has been deprecated.
19.3	119	\|(% style="width:130px" %)SDMX-CSV\|(% style="width:820px" %)The CSV data and [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] messages are not backwardly compatible with those under (% style="color:#2ecc71" %)version(%%) 2.1 due to changes to the structure of the messages needed to support new features such as the improved REST API data queries.
2.1	120	)))
	121
11.1	122	== 2.3 Information Model ==
2.1	123
	124	(((
7.4	125	(% style="width:955.039px" %)
	126	\|(% style="width:132px" %)Data Structure Definition\|(% style="width:819px" %)(((
19.3	127	The (% style="color:#2ecc71" %)version(%%) 3.0 [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]] ([[DSD>>doc:xwiki:Glossary.Data structure definition.WebHome]]) model is not directly backwardly compatible with 2.1 primarily due to the deprecation of the special MeasureDimension.
2.1	128
	129	//Conversion guidance for implementors//
	130
19.3	131	(% style="color:#2ecc71" %)Version(%%) 2.1 DSDs can be converted to the 3.0 model by creating a [[measure>>doc:xwiki:Glossary.Measure.WebHome]] with the “[[MEASURE>>doc:xwiki:Glossary.Measure.WebHome]]” (% style="color:#2ecc71" %)concept(%%) role applied as described in paragraph 3.5.
2.1	132
19.3	133	(% style="color:#2ecc71" %)Version(%%) 3.0 DSDs cannot be reliably converted to the 2.1 model due to the introduction of new features such as multiple [[measures>>doc:xwiki:Glossary.Measure.WebHome]] and value arrays for [[measures>>doc:xwiki:Glossary.Measure.WebHome]] and [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]].
2.1	134	)))
7.4	135	\|(% style="width:132px" %)Structure mapping model\|(% style="width:819px" %)(((
19.3	136	The structure mapping model has changed significantly in (% style="color:#2ecc71" %)version(%%) 3.0 with deprecation of the [[Structure Set>>doc:xwiki:Glossary.Structure set.WebHome]] [[maintainable artefact>>doc:xwiki:Glossary.Maintainable artefact.WebHome]] and introduction of five new ones: [[Representation>>doc:xwiki:Glossary.Representation.WebHome]] (% style="color:#2ecc71" %)Map(%%) and four variants of [[item scheme>>doc:xwiki:Glossary.Item scheme.WebHome]] (% style="color:#2ecc71" %)map(%%).
2.1	137
	138	//Conversion guidance for implementors//
	139
19.3	140	(% style="color:#2ecc71" %)Version(%%) 2.1 [[structure sets>>doc:xwiki:Glossary.Structure set.WebHome]] can be practically converted to the (% style="color:#2ecc71" %)version(%%) 3.0 structure mapping model.
2.1	141
19.3	142	Conversion from the (% style="color:#2ecc71" %)version(%%) 3.0 structure mapping model to 2.1 is generally possible. However, when attempting to convert mapping rules from 2.1 to 3.0 and back to 2.1, the resulting [[Structure Set>>doc:xwiki:Glossary.Structure set.WebHome]] will not be precisely the same as the original. In converting to (% style="color:#2ecc71" %)version(%%) 3.0, the system must generate IDs for each of the new [[maintainable artefacts>>doc:xwiki:Glossary.Maintainable artefact.WebHome]], but details of the original [[Structure Set>>doc:xwiki:Glossary.Structure set.WebHome]] [[artefacts>>doc:xwiki:Glossary.Artefact.WebHome]] are lost.
2.1	143	)))
7.4	144	\|(% style="width:132px" %)Reference metadata model\|(% style="width:819px" %)(((
19.3	145	The [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] model has changed in (% style="color:#2ecc71" %)version(%%) 3.0 with modifications to the role of the [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]], [[Metadata Structure Definition>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] and [[Metadataflow>>doc:xwiki:Glossary.Metadataflow.WebHome]] [[artefacts>>doc:xwiki:Glossary.Artefact.WebHome]]. Metadata [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]] and Metadata Provider Scheme have been added. Metadatasets are now identifiable.
2.1	146
19.3	147	(% style="color:#2ecc71" %)Version(%%) 2.1 [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] models are not valid in (% style="color:#2ecc71" %)version(%%) 3.0.
2.1	148
	149	//Conversion guidance for implementors//
	150
19.3	151	A (% style="color:#2ecc71" %)version(%%) 2.1 [[Metadata Structure Definition>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] can be converted to the (% style="color:#2ecc71" %)version(%%) 3.0 model under some circumstances, but target information is either lost or has to be translated into a [[metadataflow>>doc:xwiki:Glossary.Metadataflow.WebHome]]. Further, conversion of a [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]] for collecting [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] against a [[dataset>>doc:xwiki:Glossary.Data set.WebHome]] would need to make changes to the [[dataset>>doc:xwiki:Glossary.Data set.WebHome]]’s [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]]. As the [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]] may not actually be specified, judgement would need to be taken, perhaps determining the most likely candidate by examining which already have metadata reported against their [[datasets>>doc:xwiki:Glossary.Data set.WebHome]]. A 2.1 metadata report could be converted to a (% style="color:#2ecc71" %)version(%%) 3.0 Metadataset if it is attached to a structure, but requires a Metadata [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]] which would need to be created if not already in existence.
2.1	152
19.3	153	Conversion from the (% style="color:#2ecc71" %)version(%%) 3.0 model to (% style="color:#2ecc71" %)version(%%) 2.1 cannot be performed reliably. The process would need target information to be derived from analysis of the [[Metadataflows>>doc:xwiki:Glossary.Metadataflow.WebHome]] and Metadata [[Provision Agreements>>doc:xwiki:Glossary.Provision agreement.WebHome]]. Depending on the complexity it may not be possible to express that information in a (% style="color:#2ecc71" %)version(%%) 2.1 [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]].
2.1	154	)))
7.4	155	\|(% style="width:132px" %)Constraint model\|(% style="width:819px" %)(((
19.3	156	The (% style="color:#2ecc71" %)version(%%) 2.1 Content (% style="color:#2ecc71" %)Constraint(%%) [[artefact>>doc:xwiki:Glossary.Artefact.WebHome]] has been deprecated in (% style="color:#2ecc71" %)version(%%) 3.0 and replaced by the Data (% style="color:#2ecc71" %)Constraint(%%) for data, and the Metadata (% style="color:#2ecc71" %)Constraint(%%) for reference metadata.
2.1	157
	158	//Conversion guidance for implementors//
	159
19.3	160	2.1 Content (% style="color:#2ecc71" %)Constraints(%%) can be converted without loss to the equivalent (% style="color:#2ecc71" %)version(%%) 3.0 Data (% style="color:#2ecc71" %)Constraint(%%) model.
2.1	161
	162	Conversion from 3.0 to 2.1 presents challenges where wildcards have been used, in those cases requiring expansion of the wildcard into explicit values.
	163	)))
7.4	164	\|(% style="width:132px" %)Hierarchical codelist structures\|(% style="width:819px" %)(((
19.3	165	The (% style="color:#2ecc71" %)version(%%) 2.1 Hierarchical Codelist [[artefact>>doc:xwiki:Glossary.Artefact.WebHome]] has been deprecated in (% style="color:#2ecc71" %)version(%%) 3.0 and replaced by two new [[artefacts>>doc:xwiki:Glossary.Artefact.WebHome]], [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] and [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] Association.
2.1	166
	167	//Conversion guidance for implementors//
	168
19.3	169	(% style="color:#2ecc71" %)Version(%%) 2.1 Hierarchical Codelists can be successfully converted to the (% style="color:#2ecc71" %)version(%%) 3.0 [[hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] model. Information on which [[artefacts>>doc:xwiki:Glossary.Artefact.WebHome]] to link the [[hierarchies>>doc:xwiki:Glossary.Hierarchy.WebHome]] to on what context would need to be added as a separate procedure.
2.1	170
19.3	171	Conversion from the (% style="color:#2ecc71" %)version(%%) 3.0 model to (% style="color:#2ecc71" %)version(%%) 2.1 is possible, but with loss of the linking information
2.1	172	)))
	173	)))
	174
	175	= 3 Information Model =
	176
11.1	177	== 3.1 Version 3.0 Information Model ==
2.1	178
	179	[[image:SDMX 3-0-0 Major Changes FINAL-1.0_en_6fc573fe.png\|\|height="404" width="718"]]
	180
	181	//Figure 1 Version 3.0 simplified Information Model UML class diagram with ‘heat map’ illustrating the areas with most change//
	182
19.3	183	The schematic above is a simplified UML class diagram of the [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]] 3.0 information model illustrating the major areas of change as a ‘heat (% style="color:#2ecc71" %)map(%%)’. Darker colours indicate where new structures have been added in (% style="color:#2ecc71" %)version(%%) 3.0 or where structures have been significantly changed.
2.1	184
19.3	185	A number of ancillary structures including organisation schemes, process and [[reporting taxonomy>>doc:xwiki:Glossary.Reporting taxonomy.WebHome]] are unchanged and have not been shown. Similarly, Organisation Scheme (% style="color:#2ecc71" %)Map(%%) and [[Reporting Taxonomy>>doc:xwiki:Glossary.Reporting taxonomy.WebHome]] (% style="color:#2ecc71" %)Map(%%) have been omitted for simplicity. A schematic of the 2.1 model is given in Appendix A for comparison purposes.
2.1	186
11.1	187	== 3.2 Key Changes from Version 2.1 ==
2.1	188
	189	New Maintainable Artefacts
	190
19.3	191	* Structure (% style="color:#2ecc71" %)Map
	192	* [[Representation>>doc:xwiki:Glossary.Representation.WebHome]] (% style="color:#2ecc71" %)Map
	193	* Organisation Scheme (% style="color:#2ecc71" %)Map
	194	* (% style="color:#2ecc71" %)Concept(%%) Scheme (% style="color:#2ecc71" %)Map
	195	* Category Scheme (% style="color:#2ecc71" %)Map
	196	* Reporting Taxonomy (% style="color:#2ecc71" %)Map
2.1	197	* Value List
19.3	198	* [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]]
	199	* [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] Association
	200	* Metadata (% style="color:#2ecc71" %)Constraint
	201	* Data (% style="color:#2ecc71" %)Constraint
2.1	202	* Metadata Provision Agreement
	203	* Metadata Provider Scheme
	204	* Metadataset
	205
	206	New Identifiable Artefacts
	207
	208	* GeoFeatureSetCode
	209	* GeoGridCode
	210	* Metadata Provider
	211
	212	Removed Maintainable Artefacts
	213
19.3	214	* Structure Set – replaced by Structure (% style="color:#2ecc71" %)Map(%%) and the four [[item scheme>>doc:xwiki:Glossary.Item scheme.WebHome]] maps
	215	* Hierarchical Codelist – replaced by [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] and [[Hierarchy>>doc:xwiki:Glossary.Hierarchy.WebHome]] Association
	216	* (% style="color:#2ecc71" %)Constraint(%%) – replaced by Data (% style="color:#2ecc71" %)Constraint(%%) and Metadata (% style="color:#2ecc71" %)Constraint
2.1	217
	218	Changed Maintainable Artefacts
	219
19.3	220	* Data Structure Definition – support for microdatasets and [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] linked to data
	221	* Metadataflow – simplifies exchange of [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]], in particular those linked to structures
	222	* Metadata Structure Definition – simplified model for [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]]
2.1	223	* Codelist – support for codelist extension and geospatial specialised codelists (GeographicCodelist, GeoGridCodelist)
19.3	224	* [[VTL>>doc:xwiki:Glossary.Validation and transformation language.WebHome]] Mapping Scheme – [[VTL>>doc:xwiki:Glossary.Validation and transformation language.WebHome]] (% style="color:#2ecc71" %)Concept(%%) Mapping Scheme removed to align the [[VTL>>doc:xwiki:Glossary.Validation and transformation language.WebHome]] / [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]] interface with the 3.0 model
2.1	225
19.3	226	New [[Component>>doc:xwiki:Glossary.Component.WebHome]] [[Representation>>doc:xwiki:Glossary.Representation.WebHome]] Types
2.1	227
	228	* GeospatialInformation – a string type where the value is an expression defining a set of geographical features using a purpose-designed syntax
	229
10.2	230	== 3.3 Areas Unchanged from Version 2.1 ==
2.1	231
19.3	232	The following areas of the information model are unchanged from (% style="color:#2ecc71" %)version(%%) 2.1:
2.1	233
	234	* Categories
	235	* Concepts
	236	* Data providers
	237	* Agencies
	238	* Data consumers
19.3	239	* [[VTL>>doc:xwiki:Glossary.Validation and transformation language.WebHome]] transformation and expressions – with the exception of [[VTL>>doc:xwiki:Glossary.Validation and transformation language.WebHome]] mapping scheme as already noted
2.1	240	* Reporting taxonomy
	241	* Process
	242
10.2	243	== 3.4 Reference Metadata ==
2.1	244
19.3	245	[[Reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] has been substantially re-designed for (% style="color:#2ecc71" %)version(%%) 3.0 to simplify the model and better support practical use cases.
2.1	246
16.2	247	(% class="wikigeneratedid" id="HSimplifyMetadataStructureDefinition" %)
	248	Simplify Metadata Structure Definition
19.3	249	The [[Metadata Structure Definition>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] ([[MSD>>doc:xwiki:Glossary.Metadata structure definition.WebHome]]) has been simplified to remove target information, and the support of multiple report structures. The [[MSD>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] now only contains Metadata [[Attributes>>doc:xwiki:Glossary.Attribute.WebHome]] which are used to define the structure of a report.
2.1	250
	251	[[image:SDMX 3-0-0 Major Changes FINAL-1.0_en_ad5f5c97.png\|\|height="346" width="494"]]
	252
	253	//Figure 2 version 2.1 Metadata Structure Definition (MSD)//
	254
	255	[[image:SDMX 3-0-0 Major Changes FINAL-1.0_en_f2695ed5.png\|\|height="172" width="374"]]
	256
	257	//Figure 3 the simplified version 3.0 MSD//
	258
15.7	259	(% class="wikigeneratedid" id="HChangetoreferencemetadatareportedagainstdata" %)
	260	Change to reference metadata reported against data
2.1	261
19.3	262	(% class="wikigeneratedid" id="HChangetoreferencemetadatareportedagainstdata" %)
	263	[[Reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] associated with [[datasets>>doc:xwiki:Glossary.Data set.WebHome]], data series or observations are now reported with the data. The [[dataset>>doc:xwiki:Glossary.Data set.WebHome]]’s [[DSD>>doc:xwiki:Glossary.Data structure definition.WebHome]] must reference an [[MSD>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] to define the structure of its [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]]. In practice [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] for data are transmitted as part of the data message. The metadata [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] are treated in a similar way to the data [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] appearing in the message at the [[dataset>>doc:xwiki:Glossary.Data set.WebHome]], data series or individual observation (% style="color:#2ecc71" %)level(%%) as appropriate. In contrast to simple data [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]], metadata [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] defined by an [[MSD>>doc:xwiki:Glossary.Metadata structure definition.WebHome]] can be organised into a hierarchical structure as illustrated in Figure 3 above. For this reason, metadata [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] appear in data messages structured in the same way as metadata messages.
2.1	264
19.3	265	The [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] example below is an excerpt from a structure specific data message illustrating reporting of [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] with a hierarchical structure at the observation (% style="color:#2ecc71" %)level(%%).
	266
2.1	267	For completeness, the excerpt also shows:
	268
19.3	269	* OBS_STATUS – a simple observation-(% style="color:#2ecc71" %)level(%%) data [[attribute>>doc:xwiki:Glossary.Attribute.WebHome]]
	270	* TITLE – a multi-lingual data [[attribute>>doc:xwiki:Glossary.Attribute.WebHome]]
	271	* SOURCE_AGENCY – a multi-value data [[attribute>>doc:xwiki:Glossary.Attribute.WebHome]]
2.1	272
13.2	273	> <Obs xsi:type="dsd:ObsType" OBS_VALUE="112" OBS_STAUS=”A” TIME_PERIOD="2010-09">
13.3	274	> <!—- complex multi-value and multi-lingual data attributes ~-~->
	275	> <Comp id="TITLE" xsi:type="ns1:TITLE_ATTRIBUTE">
	276	> <Value>
	277	> <common:Text xml:lang="en">Some English Text</common:Text>
	278	> <common:Text xml:lang="fr">Quelques textes en anglais</common:Text>
	279	> </Value>
	280	> </Comp>
	281	> <Comp id="SOURCE_AGENCY" xsi:type="ns1:SOURCE_AGENCY_ATTRIBUTE">
	282	> <Value>4F0</Value>
	283	> <Value>4D0</Value>
	284	> <Value>CZ2</Value>
	285	> </Comp>
	286	> <!—- metadata attributes are reported like in metadata messages ~-~->
13.4	287	> <Metadata>
	288	> <Attribute id="COLLECTION">
	289	> <Attribute id="METHOD">
	290	> <Text lang="en">AAA</Text>
14.1	291	> </Attribute>
13.4	292	> </Attribute>
14.1	293	> <Attribute id="CONTACT">
	294	> <Value>CONTACT 1</Value>
	295	> <Attribute id="NAME">
	296	> <Value>Contact 1 Name 1</Value>
	297	> </Attribute>
	298	> <Attribute id="NAME">
	299	> <Value>Contact 1 Name 2</Value>
	300	> </Attribute>
13.4	301	> </Attribute>
	302	> <Attribute id="CONTACT">
14.1	303	> <Value>CONTACT 2</Value>
13.4	304	> <Attribute id="NAME">
	305	> <Value>Contact 2 Name 1</Value>
14.1	306	> </Attribute>
	307	> <Attribute id="NAME">
	308	> <Value>Contact 2 Name 2</Value>
	309	> </Attribute>
	310	> </Attribute>
	311	> </Metadata>
13.3	312	> </Obs>
2.1	313
15.6	314	(% class="wikigeneratedid" id="HNew-MetadataProvisionAgreement" %)
	315	New - Metadata Provision Agreement
2.1	316
19.3	317	(% class="wikigeneratedid" id="HNew-MetadataProvisionAgreement" %)
	318	In (% style="color:#2ecc71" %)version(%%) 2.1 a [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]] could be used to report information against a [[Dataflow>>doc:xwiki:Glossary.Dataflow.WebHome]] or [[Metadataflow>>doc:xwiki:Glossary.Metadataflow.WebHome]]. From (% style="color:#2ecc71" %)version(%%) 3.0 this is managed by two separate structures, the Data [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]] and the Metadata [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]].
	319
15.6	320	(% class="wikigeneratedid" id="HMovetargettoMetadataflowandMetadataProvisionAgreement" %)
	321	Move target to Metadataflow and Metadata Provision Agreement
19.3	322	For [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] that is reported against structures, the allowable targets information which is used to specify what structures the [[reference metadata>>doc:xwiki:Glossary.Reference metadata.WebHome]] can be reported against, has moved to the [[Metadataflow>>doc:xwiki:Glossary.Metadataflow.WebHome]] and can be further refined in the Metadata [[Provision Agreement>>doc:xwiki:Glossary.Provision agreement.WebHome]].
2.1	323
15.6	324	(% class="wikigeneratedid" id="HAddmaintainablepropertiestoreferencemetadata" %)
	325	Add maintainable properties to reference metadata
19.3	326	A Metadataset now has mandatory identification information, (owner id, id, (% style="color:#2ecc71" %)version(%%)) enabling metadata providers to uniquely identify their reports for create, update or delete maintenance operations.
2.1	327
10.2	328	== 3.5 Microdata Exchange ==
2.1	329
19.4	330	Several changes have been made the [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]] to support microdata use cases in addition to aggregated time series.
2.1	331
15.5	332	(% class="wikigeneratedid" id="HMultiplemeasures" %)
19.4	333	Multiple measuresMultiple [[measures>>doc:xwiki:Glossary.Measure.WebHome]] are a common characteristic of microdatasets. To support this use case, the MeasureDimension has been deprecated and replaced with the option to define zero or more [[measures>>doc:xwiki:Glossary.Measure.WebHome]]. [[Measures>>doc:xwiki:Glossary.Measure.WebHome]] now act like any other [[component>>doc:xwiki:Glossary.Component.WebHome]] in that they use (% style="color:#2ecc71" %)concepts(%%), can have their own local coded or uncoded [[representation>>doc:xwiki:Glossary.Representation.WebHome]] defined within the [[Data Structure Definition>>doc:xwiki:Glossary.Data structure definition.WebHome]], and can be either mandatory or conditional. Creating a [[measure>>doc:xwiki:Glossary.Measure.WebHome]] with the “[[MEASURE>>doc:xwiki:Glossary.Measure.WebHome]]” (% style="color:#2ecc71" %)concept(%%) role applied emulates the (% style="color:#2ecc71" %)version(%%) 2.1 MeasureDimension behaviour as illustrated in the [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] example below:
2.1	334
15.1	335	> <str:MeasureList id=”MeasureDescriptor”>
	336	> <str:Measure id=”OBS_VALUE” minOccurs=”1” maxOccurs=”1” usage=”mandatory” > <str:ConceptIdentity>
	337	> <Ref id=”OBS_VALUE” maintainableParentID=”CONCEPTS” agencyID=”SDMX” maintainableParentVersion=”1.0.0” />
	338	> </str:ConceptIdentity>
	339	> <str:LocalRepresentation>
	340	> <str:TextFormat textType=”String” isMultiLingual=”true” />
	341	> </str:LocalRepresentation>
	342	> <str:ConceptRole>
	343	> <Ref id=”MEASURE” maintainableParentID=”SDMX_CONCEPT_ROLES” agencyID=”SDMX” maintainableParentVersion=”1.0.0” />
	344	> </str:ConceptRole>
	345	> </str:Measure>
	346	> ...
	347	> <str:Measure>
	348	> </str:MeasureList>
2.1	349
15.4	350	(% class="wikigeneratedid" id="HMulti-valuemeasuresandattributes" %)
	351	Multi-value measures and attributes
2.1	352
19.5	353	(% class="wikigeneratedid" id="HMulti-valuemeasuresandattributes" %)
	354	Both [[measures>>doc:xwiki:Glossary.Measure.WebHome]] and [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] have been extended with the option to take ‘arrays’ of 193 multiple coded or uncoded values. This supports use cases like multiple observation 194 status flags. New //minOccurs// and //maxOccurs// properties define the valid number of 195 values. The //usage// property separately defines whether the [[measure>>doc:xwiki:Glossary.Measure.WebHome]] or [[attribute>>doc:xwiki:Glossary.Attribute.WebHome]] is //mandatory// or optional. In the [[SDMX-ML>>doc:xwiki:Glossary.SDMX-ML.WebHome]] [[measure>>doc:xwiki:Glossary.Measure.WebHome]] example above, the properties //minOccurs=”1” maxOccurs=”1” usage=”mandatory”// specify that OBS_VALUE must be 198 reported, and can only consist of a single value.
	355
15.4	356	(% class="wikigeneratedid" id="HAttributesrelationshiptomeasures" %)
	357	Attributes relationship to measures
19.5	358	In addition to attaching [[attributes>>doc:xwiki:Glossary.Attribute.WebHome]] to a specific (% style="color:#2ecc71" %)level(%%) within the [[dataset>>doc:xwiki:Glossary.Data set.WebHome]], their relationship 202 to [[measures>>doc:xwiki:Glossary.Measure.WebHome]] can also be defined.
2.1	359
15.4	360	(% class="wikigeneratedid" id="HValuelists" %)
	361	Value lists
19.5	362	Value lists help in modelling microdata by providing an enumeration similar to [[code lists>>doc:xwiki:Glossary.Code list.WebHome]] 206 but allowing any string values without being restricted to the rules of [[SDMX>>doc:xwiki:Glossary.Statistical data and metadata exchange.WebHome]] identifiers. That allows ValueItems (the equivalent to [[Code>>doc:xwiki:Glossary.Code.WebHome]]) to contain symbols like ‘¥’ and ‘€’, but also means they are not identifiable.
2.1	363
10.2	364	== 3.6 Geospatial Data Exchange ==
2.1	365
19.5	366	The (% style="color:#2ecc71" %)version(%%) 3.0 model has been extended to provide explicit support for geospatial data.
2.1	367
16.3	368	(% class="wikigeneratedid" id="HGeospatialInformationtype" %)
	369	GeospatialInformation type
19.5	370	A new GeospatialInformation string type has been added which can be used as the [[representation>>doc:xwiki:Glossary.Representation.WebHome]] for any [[dimension>>doc:xwiki:Glossary.Dimension.WebHome]], [[attribute>>doc:xwiki:Glossary.Attribute.WebHome]] or measure [[component>>doc:xwiki:Glossary.Component.WebHome]]. The value which is a string expression conforming to the syntax defined in Section 6 of the technical specifications precisely defines a ‘Geo Feature Set’ – a collection of geographical features like points, lines or polygons. Its use is recommended in conjunction with the “GEO_FEATURE_SET” (% style="color:#2ecc71" %)concept(%%) role.
2.1	371
16.3	372	(% class="wikigeneratedid" id="HGeospatialcodelists" %)
	373	Geospatial code lists
2.1	374
19.5	375	(% class="wikigeneratedid" id="HGeospatialcodelists" %)
	376	Two new specialised types of [[code list>>doc:xwiki:Glossary.Code list.WebHome]] have been added where the definition of each [[code>>doc:xwiki:Glossary.Code.WebHome]] includes additional geospatial information in addition to the standard ID, name and description:
	377
2.1	378	* GeographicCodelist – each item includes an element to represent a specific Geo Feature Set which is described using the same expression syntax as for GeospatialInformation type.
19.5	379	* GeoGridCodelist – A [[code list>>doc:xwiki:Glossary.Code list.WebHome]] defining a geographical grid composed of cells representing regular squared portions of the Earth. Each item references a cell within the grid.
2.1	380
11.2	381	== 3.7 Structure Mapping ==
2.1	382
	383	The Structure Set in version 2.1 is a container for many mapping structures including Data Structure Map, Codelist Map and Concept Map. For version 3.0 the Structure Set artefact has been deprecated and replaced with a number of new maintainables giving better flexibility and reusability, specifically: Structure Map, Concept Scheme Map, Representation Map, Reporting Taxonomy Map, Category Scheme Map and Organisation Scheme Map.
	384
	385	The version 2.1 Codelist Map been replaced with Representation Map which allows mappings to be defined between any combination of Code Lists, Value Lists and noncoded representations such as text strings and numbers.
	386
15.3	387	(% class="wikigeneratedid" id="HMany-to-manysourceandtargetcomponents" %)
	388	Many-to-many source and target components
2.1	389	Structure mapping rules may be defined with both multiple source components and multiple target components in contrast to version 2.1 where only one source and target was allowed. That supports many-to-many (n-n) mapping use cases where the output of a mapping rule may be dependent on the combination of a number of input components. For instance:
	390
	391	Set the output component INDICATOR=”DE_A” if the input components are FREQ=”A” and REF_AREA=”DE”.
	392
	393	Similarly, an n-n rule may also set the values of any number of output components:
	394
	395	Set the output components FREQ=”A”, REF_AREA=”DE” if the input component INDICATOR=”DE_A”.
	396
	397	Fixed source and target
	398	The Structure Map may now define input or output components which have a fixed value.
	399
15.3	400	(% class="wikigeneratedid" id="HTimerepresentationsmapping" %)
	401	Time representations mapping
2.1	402	Non SDMX time representations may now be described in a Structure Map, allowing them to be mapped into SDMX time formats.
	403
15.3	404	(% class="wikigeneratedid" id="HRegularexpressionandsubstringmappings" %)
	405	Regular expression and substring mappings
2.1	406	All item maps allow the use of regular expressions and substrings to match source values, specifically: Concept Scheme Map, Reporting Taxonomy Map, Category Scheme Map and Organisation Scheme Map.
	407
15.3	408	(% class="wikigeneratedid" id="HItemmapsvalidityperiod" %)
	409	Item maps validity period
2.1	410	Item maps may further define the period for which the mapping is valid, meaning the mapping rule will only be applied if the row of information being mapped is within the period.
	411
11.2	412	== 3.8 Constraints ==
2.1	413
	414	Constraints in version 3.0 are modelled using two separate artefacts which replace the version 2.1 content constraint:
	415
	416	* data constraint for data; and
	417	* metadata constraint for reference metadata.
	418
	419	Metadata constraint differs from its data counterpart in having a simplified cube region model better suited to reference metadata reporting use cases and not carrying details of the constrained targets – that information instead being defined directly within the metadataflow and Metadata Provision Agreement. Thus, metadata related constraints only specify constraints to the values of metadata attributes.
	420
	421	The ‘%’ wildcard character can now be used when defining cube region constraints to match multiple codes with a single expression, for instance for economic activity, ISIC4_% matches all codes beginning with ‘ISIC4_’ avoiding the need to maintain an explicit list.
	422
	423	The validity period definition has been moved from the constraint to the individual constraining terms, specifically CubeRegion, DataKeySet and MetadataTargetRegion providing more granular control.
	424
	425	Attachment constraints have been deprecated due to a lack of use cases.
	426
11.2	427	== 3.9 Code List Extension ==
2.1	428
	429	In addition to the two new specialised geospatial forms, the option has been added to define a code list as an extension of, or by inheriting codes from, other lists. An optional prefix can be added to inherited codes to disambiguate duplicates.
	430
	431	This feature allows new code lists to be easily derived from existing lists without the need to make and manually maintain copies. When querying for extended code list structures using the REST API, the option has been added to retrieve either the definition or the materialised list. Traditional literal lists of codes continue to be supported.
	432
11.2	433	== 3.10 Discriminated Union of Code Lists ==
2.1	434
	435	Combining code list extension with wildcarded constraints solves the discriminated union of code lists problem where a classification or breakdown has multiple “variants” which are all valid but mutually exclusive. A common example is economic activity where several alternative classification schemes are in use including ISIC revisions 1 to 4 and NACE as used in the European Community.
	436
11.2	437	== 3.11 Code Hierarchies ==
2.1	438
	439	Code hierarchies allow the definition of complex hierarchies of codes from potentially multiple lists for data discovery purposes. Hierarchical Codelist has been deprecated and replaced by two new artefacts: Hierarchy – the actual hierarchy of codes, and Hierarchy Association links hierarchies directly to any other identifiable object, a capability missing 312 from the version 2.1 model. Further, the linkage can be within a particular context, for instance linking a hierarchy to a dimension within the context of a specific Dataflow (dimension REF_AREA in the context of the ECB:EXR Dataflow).
	440
	441	= 4 Versioning of Structural Metadata Artefacts =
	442
7.4	443	Version 3.0 adopts semantic versioning principles for versioning of metadata artefacts following the rules set out at __[[https:~~/~~/semver.org>>https://semver.org]] __However, this is not mandatory, and organisations may continue to use the pre-existing two-digit versioning strategy, or not to version artefacts by omitting the //version// property. The version number no longer defaults to 1.0 if not explicitly set.
2.1	444
	445	Semantic version numbers are three digits:
	446
	447	MAJOR.MINOR.PATCH
	448
	449	Where
	450
	451	* The first digit (major) indicates that changes (either new features or bug fixes) are not backward compatible.
	452	* The second digit (minor) indicates that features have been added in a backward compatible manner.
	453	* The third digit (patch) indicates that bugs have been fixed in a backward compatible manner.
	454
	455	Examples:
	456
	457	SDMX:CL_AREA(1.0.0)
	458	SDMX:CL_AREA(2.3.2)
	459
	460	== Dependency management ==
	461
	462	Additional constructs are possible for dependency management when referencing structures. For instance:
	463
16.4	464	2.3+.1 Means the currently latest available version >= “2.3.1” and < “3.0.0” (all backwards compatible versions >= “2.3.1”).
	465	2+.3.1 Means the currently latest available version >= “2.3.1” (even if not backwards compatible).
2.1	466
	467	== Draft structures ==
	468
	469	A key principle is that semantically versioned structures are immutable and must not be changed without a corresponding change to the version number, except where explicitly marked as draft using extensions to the version number.
	470
	471	MAJOR.MINOR.PATCH-EXTENSION
	472
16.5	473	1.10.0-draft Means that version 1.10.0 is still being modified and may change – equivalent to setting isFinal=false in SDMX 2.1.
	474	1.10.0-unstable Alternative to -draft.
	475	1.10.0-notfinal Alternative to -draft.
2.1	476
	477	The SDMX 2.1 isFinal property is deprecated in 3.0.
	478
	479	= 5 REST Web Services API =
	480
11.1	481	== 5.1 Simplified list of resources ==
2.1	482
	483	The version 3.0 REST API has just five main resources:
	484
	485	* structure
	486	* data
	487	* schema
	488	* availability
	489	* metadata
	490
	491	All structure and item queries have been organised under the structure resource in contrast to the version 2.1 API which specified a separate resource for each structure.
	492
	493	This and changes in the URLs and query parameters on the data, availability and metadata resources means that, with the exception of schema queries, the version 3.0 API is not backwardly compatible.
	494
11.1	495	== 5.2 Improved data queries ==
2.1	496
	497	Data queries have been changed to provide more granular selections from contexts wider than just a Dataflow.
	498
16.6	499	(% class="wikigeneratedid" id="HExtendthecontextofdataretrieval" %)
	500	Extend the context of data retrieval
2.1	501	Version 2.1 data queries always retrieved data from a single specific Dataflow. In version 3.0, the query context may be specified as:
	502
	503	* Dataflow;
	504	* Data Structure Definition – i.e., all Dataflows that use it; or
	505	* Provision Agreement – i.e., all Dataflows associated with it.
	506
	507	Data queries may also search across datasets, for instance “retrieve all data about a country”.
	508
16.6	509	(% class="wikigeneratedid" id="HComponent-basedfilters" %)
	510	Component-based filters
2.1	511	Expressions filtering on individual components can now be included as part of the data query URL.
	512
	513	/data/dataflow/ESTAT/ICP?c[REF_AREA]=CH&c[CONF_STATUS]=F
	514
16.6	515	(% class="wikigeneratedid" id="HSupportforoperators" %)
	516	Support for operators
2.1	517	Filter expressions can also include operators.
	518
16.6	519	/data/dataflow/ESTAT/ICP?c[REF_AREA]=DE&c[ICP_ITEM]=sw:01&c[TIME_PERIOD]=ge:2015
2.1	520
16.6	521	Operators include:
	522
7.4	523	(% style="width:531.039px" %)
	524	\|(% style="width:151px" %)eq\|(% style="width:378px" %)Equals
	525	\|(% style="width:151px" %)ne\|(% style="width:378px" %)Not equal to
	526	\|(% style="width:151px" %)le\|(% style="width:378px" %)Less than
	527	\|(% style="width:151px" %)ge\|(% style="width:378px" %)Greater than or equal to
	528	\|(% style="width:151px" %)sw\|(% style="width:378px" %)Starts with
2.1	529
16.7	530	(% class="wikigeneratedid" id="HSupportformultiplekeys" %)
	531	Support for multiple keys
2.1	532	Queries can now specify multiple series keys.
	533
16.7	534	(% class="wikigeneratedid" %)
2.1	535	/data/dataflow/ESTAT/ICP/1.0.0/M…A.ANR,M…A.INX,M…B.CTG
	536
11.1	537	== 5.3 Improved reference metadata queries ==
2.1	538
	539	Reference metadata queries have been improved with a number of new options to retrieve metadata reports.
	540
	541	Get metadata reports by ID
	542
	543	/metadata/metadataset/ESTAT/QUALITY_REPORT/1.0.0
	544
	545	Get metadata reports by Dataflow
	546
	547	/metadata/metadataflow/ECB/METHODOLOGY/*/FR2
	548
	549	Get metadata reports about a Data Structure Definition
	550
	551	/metadata/structure/datastructure/BIS/BIS_CBS/1.0
	552
11.1	553	== 5.4 Structural metadata maintenance ==
2.1	554
	555	Support has been added for maintenance of structural metadata.
	556
	557	HTTP verbs PUT, POST and DELETE may be used to submit SDMX-ML or SDMX-JSON structure messages to an SDMX registry for the purposes of adding, updating or deleting structural metadata artefacts.
	558
	559	= 6 XML, JSON, CSV and EDI Transmission formats =
	560
11.1	561	== 6.1 SDMX-ML ==
2.1	562
	563	The SDMX-ML XML messages have been modified and updated for version 3.0. While they broadly follow the same principles, there have been significant changes which break backward compatibility.
	564
16.8	565	(% class="wikigeneratedid" id="HStructuremessage" %)
	566	Structure message
2.1	567	The SDMX-ML structure message is used for transmission of structural metadata. It closely reflects the SDMX information model and has therefore been significantly updated for version 3.0 with the addition of new structures, modifications where structures have changed, and removal of deprecated structures like Structure Set.
	568
	569	Additionally, the way the individual artefacts are organised into ‘collections’ within the message has been significantly revised with a simpler flat structure adopted as set out in the following table:
	570
7.4	571	(% style="width:1102.04px" %)
	572	\|(% style="width:321px" %)Artefact type\|(% style="width:351px" %)Version 2.1 Collection\|(% style="width:426px" %)Version 3.0 Collection
	573	\|(% style="width:321px" %)AgencyScheme\|(% style="width:351px" %)OrganisationSchemes\|(% style="width:426px" %)AgencySchemes
	574	\|(% style="width:321px" %)DataConsumerScheme\|(% style="width:351px" %)OrganisationSchemes\|(% style="width:426px" %)DataConsumerSchemes
	575	\|(% style="width:321px" %)DataProviderScheme\|(% style="width:351px" %)OrganisationSchemes\|(% style="width:426px" %)DataProviderSchemes
	576	\|(% style="width:321px" %)MetadataProviderScheme\|(% style="width:351px" %)OrganisationSchemes\|(% style="width:426px" %)MetadataProviderSchemes
	577	\|(% style="width:321px" %)OrganisationUnitScheme\|(% style="width:351px" %)OrganisationSchemes\|(% style="width:426px" %)OrganisationUnitSchemes
	578	\|(% style="width:321px" %)GeographicCodelist\|(% style="width:351px" %)Codelists\|(% style="width:426px" %)GeographicCodelists
	579	\|(% style="width:321px" %)GeoGridCodelist\|(% style="width:351px" %)Codelists\|(% style="width:426px" %)GeoGridCodelists
	580	\|(% style="width:321px" %)ConceptScheme\|(% style="width:351px" %)Concepts\|(% style="width:426px" %)ConceptSchemes
	581	\|(% style="width:321px" %)ValueList\|(% style="width:351px" %)Codelists\|(% style="width:426px" %)ValueLists
	582	\|(% style="width:321px" %)StructureMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)StructureMaps
	583	\|(% style="width:321px" %)RepresentationMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)RepresentationMaps
	584	\|(% style="width:321px" %)ConceptSchemeMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)ConceptSchemeMaps
	585	\|(% style="width:321px" %)CategorySchemeMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)CategorySchemeMaps
	586	\|(% style="width:321px" %)OrganisationSchemeMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)OrganisationSchemeMaps
	587	\|(% style="width:321px" %)ReportingTaxonomyMap\|(% style="width:351px" %)StructureMappings\|(% style="width:426px" %)ReportingTaxonomyMaps
	588	\|(% style="width:321px" %)DataConstraint\|(% style="width:351px" %)Constraints\|(% style="width:426px" %)DataConstraints
	589	\|(% style="width:321px" %)MetadataConstraint\|(% style="width:351px" %)Constraints\|(% style="width:426px" %)MetadataConstraints
	590	\|(% style="width:321px" %)MetadataProvisionAgreement\|(% style="width:351px" %)ProvisionAgreement\|(% style="width:426px" %)MetadataProvisionAgreements
	591	\|(% style="width:321px" %)CustomTypeScheme\|(% style="width:351px" %)CustomTypes\|(% style="width:426px" %)CustomTypeSchemes
	592	\|(% style="width:321px" %)VtlMappingScheme\|(% style="width:351px" %)VtlMappings\|(% style="width:426px" %)VtlMappingSchemes
	593	\|(% style="width:321px" %)NamePersonalisationScheme\|(% style="width:351px" %)NamePersonalisations\|(% style="width:426px" %)NamePersonalisationSchemes
	594	\|(% style="width:321px" %)RulesetScheme\|(% style="width:351px" %)Rulesets\|(% style="width:426px" %)RulesetSchemes
	595	\|(% style="width:321px" %)TransformationScheme\|(% style="width:351px" %)Transformations\|(% style="width:426px" %)TransformationSchemes
	596	\|(% style="width:321px" %)UserDefinedOperatorScheme\|(% style="width:351px" %)UserDefinedOperators\|(% style="width:426px" %)UserDefinedOperatorSchemes
2.1	597
	598	No changes have been made to the way the following artefacts are organised in the structure message:
	599
7.4	600	(% style="width:1106.04px" %)
	601	\|(% style="width:326px" %)Artefact type\|(% style="width:776px" %)Collection
	602	\|(% style="width:326px" %)Dataflow\|(% style="width:776px" %)Dataflows
	603	\|(% style="width:326px" %)Metadataflow\|(% style="width:776px" %)Metadataflows
	604	\|(% style="width:326px" %)CategoryScheme\|(% style="width:776px" %)CategorySchemes
	605	\|(% style="width:326px" %)Categorisation\|(% style="width:776px" %)Categorisations
	606	\|(% style="width:326px" %)Codelist\|(% style="width:776px" %)Codelists
	607	\|(% style="width:326px" %)Hierarchy\|(% style="width:776px" %)Hierarchies
	608	\|(% style="width:326px" %)HierarchyAssociation\|(% style="width:776px" %)HierarchyAssociations
	609	\|(% style="width:326px" %)MetadataStructure\|(% style="width:776px" %)MetadataStructures
	610	\|(% style="width:326px" %)DataStructure\|(% style="width:776px" %)DataStructures
	611	\|(% style="width:326px" %)ReportingTaxonomy\|(% style="width:776px" %)ReportingTaxonomies
	612	\|(% style="width:326px" %)Process\|(% style="width:776px" %)Processes
	613	\|(% style="width:326px" %)ProvisionAgreement\|(% style="width:776px" %)ProvisionAgreements
2.1	614
	615	From version 3.0, collections can appear in any order within a structure message.
	616
16.8	617	(% class="wikigeneratedid" id="HDatamessages" %)
	618	Data messages
2.1	619	All legacy SDMX-ML data messages have been deprecated with the exception of Structure Specific Data which becomes the sole standard format for transmission of SDMX data in XML in version 3.0.
	620
	621	Specifically, the following data messages are not supported in version 3.0:
	622
	623	* SDMX-ML 1.0/2.0 Generic (time-series) data message
	624	* SDMX-ML 1.0/2.0 Compact (time-series) data message
	625	* SDMX-ML 1.0/2.0 Utility (time-series) data message
	626	* SDMX-ML 1.0/2.0 Cross-Sectional data message
	627	* SDMX-ML 2.1 Generic data messages (for observations, time-series and crosssectional data)
	628
	629	The Structure Specific Data message has been extended to support the transmission of microdata sets, in particular those with multiple measures and array values for measures and attributes.
	630
	631	As detailed in paragraph 3.4, the message now additionally allows data’s reference metadata to be reported as an integral part of the dataset. Like data attributes, these metadata attributes are included in the data message at the dataset, series or observation level as appropriate.
	632
	633	The time series variant of the Structure Specific Data message is no longer used.
	634
16.8	635	(% class="wikigeneratedid" id="HReferencemetadatamessage" %)
	636	Reference metadata message
2.1	637	The Generic Metadata message remains the standard format for transmission of reference metadata sets in XML but has been modified to support the revised version 3.0 reference metadata model.
	638
16.8	639	(% class="wikigeneratedid" id="HRegistrystructuralmetadata2018query2019messages" %)
	640	Registry structural metadata ‘query’ messages
2.1	641	As a consequence of the deprecation of the SOAP API and standardisation on REST, the structural metadata ‘query’ messages have all been removed. In version 3.0, querying an SDMX Registry for structural metadata is performed solely using REST GET.
	642
16.8	643	(% class="wikigeneratedid" id="HStructurereferencing" %)
	644	Structure referencing
2.1	645	The option to reference structures using Agency, ID and Version has been removed. From SDMX version 3.0 URN is used for all referencing purposes with the exception of local references such as where groups reference dimensions within a DSD.
	646
11.1	647	== 6.2 SDMX-JSON ==
2.1	648
	649	Like SDMX-ML, the SDMX-JSON messages have been significantly modified and updated for version 3.0. They are not backwardly compatible with version 2.1.
	650
16.9	651	(% class="wikigeneratedid" id="HStructuremessage-1" %)
	652	Structure message
2.1	653	The SDMX-JSON structure message closely replicates the SDMX-ML equivalent. Like that of SDMX-ML it has been updated to align it with the version 3.0 information model with addition, deletion and modification of artefacts as required. The organisation of the structure collections has also been revised as detailed in paragraph 6.1.
	654
16.9	655	(% class="wikigeneratedid" id="HDatamessage" %)
	656	Data message
2.1	657	The SDMX-JSON data message has similarly be updated. Additional changes have been made to allow a single message to carry data from multiple datasets with potentially different Data Structure Definitions to support REST data queries of the form “retrieve all data about a country”. For this reason, the version 3.0 SDMX-JSON is not backwardly compatible with version 2.1 data messages. Support has been added for the transmission of microdata and reporting of reference metadata on data as an integral part of the dataset.
	658
16.9	659	(% class="wikigeneratedid" id="HReferencemetadatamessage-1" %)
	660	Reference metadata message
2.1	661	The SDMX-JSON metadata message has also been updated to support the version 3.0 reference metadata and Metadataset specifications.
	662
16.9	663	(% class="wikigeneratedid" id="HStructurereferencing-1" %)
	664	Structure referencing
2.1	665	As for SDMX-ML, the option to reference structures using Agency, ID and Version has been removed with URN used for all non-local referencing purposes.
	666
11.1	667	== 6.3 SDMX-CSV ==
2.1	668
	669	CSV in SDMX is used transmission of data and reference metadata only.
	670
17.1	671	(% class="wikigeneratedid" id="HDatamessage-1" %)
	672	Data message
2.1	673	The SDMX-CSV data message has been modified to align with the version 3.0 information model, support the enhanced REST API and ensure that data can be freely converted to and from the XML and JSON formats without loss. These changes include:
	674
	675	* An additional column identifying the type if the artefact defining the structure of the data: “dataflow”, “datastructure” or “dataprovision”; • A column for the structure artefact’s identification of the form
	676
	677	ESTAT:NA_MAIN(1.6.0) which replaces the dataflow identifier in version 2.1; and
	678
	679	* A column for the dataset action: information, append, replace or delete, which is consistent with both the the SDMX-ML and SDMX-JSON data messages.
	680
17.1	681	(% class="wikigeneratedid" id="HReferencemetadatamessage-2" %)
	682	Reference metadata message
2.1	683	The SDMX-CSV metadata message is new for version 3.0 and, like the SDMX-ML and SDMX-JSON equivalents, is used for the transmission reference metadata sets.
	684
18.1	685	== 6.4 EDI deprecation ==
2.1	686
	687	The EDI format for transmission of both structures and data has been deprecated. Version 3.0 is therefore not backwardly compatible with legacy EDI messages.
	688
	689	= Appendix A – Version 2.1 Information Model =
	690
	691	[[image:SDMX 3-0-0 Major Changes FINAL-1.0_en_5f21cdf9.png\|\|height="319" width="718"]]