Changes for page SDMX 3.0 Standards. Section 1. Framework for SDMX technical standards

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  **Section 2** **SDMX Information Model** – the [[SDMX information model>>doc:Glossary.SDMX Information Model.WebHome]] is a standardised object model for modelling [[statistical domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] centring on the structure of their data and [[metadata sets>>doc:Glossary.Metadata set.WebHome]], the coding schemes used for classification, and the rules for controlling the exchange of data and metadata between organisations. This document provides a UML specification with supporting narrative.
--**Section 5** **SDMX Registry Specification** – an [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] ‘registry’ acts as a repository for [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] and provisioning information, and a registry of data and metadata sources. This document sets out the specification.
++**Section 5** **SDMX Registry Specification** – an [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]][[ ‘registry>>doc:Glossary.SDMX Registry.WebHome]]’ acts as a repository for [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] and provisioning information, and a registry of data and metadata sources. This document sets out the specification.
  **Section 6** **SDMX Technical Notes** – detailed technical guidance for implementors of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] standard.
--The following are published on the GitHub repository of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Standards Technical Working Group ([[__https:~~/~~/github.com/sdmx-twg__>>https://https:github.comsdmx-twg]]):
++The following are published on the GitHub repository of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Standards Technical Working Group ([[__https:~~/~~/github.com/sdmx-twg__>>https://github.com/sdmx-twg]]):
  (% class="wikigeneratedid" id="Hsdmx-twg2Fsdmx-rest2013RESTAPI" %)
  **sdmx-twg/sdmx-rest – REST API**
@@ -59,21 +59,21 @@
  = 2 Change History =
--The 2.0 (% style="color:#e74c3c" %)version(%%) of this standard represented a significant increase in scope, and also provided more complete support in those areas covered in the (% style="color:#e74c3c" %)version(%%) 1.0 specification. (% style="color:#e74c3c" %)Version(%%) 2.0 of this standard is backward-compatible with (% style="color:#e74c3c" %)version(%%) 1.0, so that existing implementations can be easily migrated to conformance with (% style="color:#e74c3c" %)version(%%) 2.0.
++The 2.0 version of this standard represented a significant increase in scope, and also provided more complete support in those areas covered in the version 1.0 specification. Version 2.0 of this standard is backward-compatible with version 1.0, so that existing implementations can be easily migrated to conformance with version 2.0.
--The 2.1 (% style="color:#e74c3c" %)version(%%) of this standard represents a set of changes resulting from several years of implementation experience with the 2.0 standard. The changes do not represent a major increase in scope or functionality, but do correct some bugs, and add functionalities in some cases. Major changes in [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] include a much stronger alignment of the XML Schemas with the Information Model, to emphasize inheritance and object-oriented features, and increased precision and flexibility in the attachment of metadata reports to specific objects in the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Information Model.
++The 2.1 version of this standard represents a set of changes resulting from several years of implementation experience with the 2.0 standard. The changes do not represent a major increase in scope or functionality, but do correct some bugs, and add functionalities in some cases. Major changes in [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] include a much stronger alignment of the XML Schemas with the Information Model, to emphasize inheritance and object-oriented features, and increased precision and flexibility in the attachment of metadata reports to specific objects in the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Information Model.
--The 3.0 (% style="color:#e74c3c" %)version(%%) incorporates new features, improvements and changes arising from the collective knowledge gained from a decade of operating experience with the 2.1 standard. In pursuit of modernisation and simplification, features considered obsolete have been deprecated – in particular the EDI transmission format, the lesser-used XML data messages and the SOAP web services API. Many areas remain backwardly compatible with 2.1, but there are some breaking changes where the information model has been redesigned to better support practical use case. Structure mapping and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] are examples. The opportunity has been taken to revise the RESTful web services API which is also not backwardly compatible, but benefits from a rationalisation and better organisations of resources, and a much richer data query URL syntax.
++The 3.0 version incorporates new features, improvements and changes arising from the collective knowledge gained from a decade of operating experience with the 2.1 standard. In pursuit of modernisation and simplification, features considered obsolete have been deprecated – in particular the EDI transmission format, the lesser-used XML data messages and the SOAP web services API. Many areas remain backwardly compatible with 2.1, but there are some breaking changes where the information model has been redesigned to better support practical use case. Structure mapping and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] are examples. The opportunity has been taken to revise the RESTful web services API which is also not backwardly compatible, but benefits from a rationalisation and better organisations of resources, and a much richer data query URL syntax.
  == 2.1 Major Changes from 1.0 to 2.0 ==
--* **[[Reference Metadata>>doc:Glossary.Reference metadata.WebHome]]**: In addition to describing and specifying data structures and formats (along with related [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]), the (% style="color:#e74c3c" %)version(%%) 2.0 specification also provides for the exchange of metadata which is distinct from the [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] in the 1.0 (% style="color:#e74c3c" %)version(%%). This [[category>>doc:Glossary.Category.WebHome]] includes “reference” metadata (regarding data quality, methodology, and similar types – it can be configured by the user to include whatever (% style="color:#e74c3c" %)concepts(%%) require reporting); metadata related to data provisioning ([[release calendar>>doc:Glossary.Release policy - release calendar.WebHome]] information, description of the data and metadata provided, etc.); and metadata relevant to the exchange of categorization schemes.
--* **SDMX Registry**: Provision is made in the 2.0 standard for standard communication with registry services, to support a data-sharing model of statistical exchange. These services include registration of data and metadata, querying of registered data and metadata, and subscription.
++* **[[Reference Metadata>>doc:Glossary.Reference metadata.WebHome]]**: In addition to describing and specifying data structures and formats (along with related [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]), the version 2.0 specification also provides for the exchange of metadata which is distinct from the [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] in the 1.0 version. This [[category>>doc:Glossary.Category.WebHome]] includes “reference” metadata (regarding data quality, methodology, and similar types – it can be configured by the user to include whatever (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) require reporting); metadata related to data provisioning ([[release calendar>>doc:Glossary.Release policy - release calendar.WebHome]] information, description of the data and metadata provided, etc.); and metadata relevant to the exchange of categorization schemes.
++* [[**SDMX Registry**>>doc:Glossary.SDMX Registry.WebHome]]: Provision is made in the 2.0 standard for standard communication with registry services, to support a data-sharing model of statistical exchange. These services include registration of data and metadata, querying of registered data and metadata, and subscription.
  * **[[Structural Metadata>>doc:Glossary.Structural metadata.WebHome]]**: The support for exchange of statistical data and related [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] has been expanded. Some support is provided for qualitative data; data cube structures are described; [[hierarchical code lists>>doc:Glossary.Hierarchical code list.WebHome]] are supported; relationships between data structures can be expressed, providing support for extensibility of data structures; 101 and the description of functional dependencies within cubes are supported.
  == 2.2 Major Changes from 2.0 to 2.1 ==
--* **Simplification of the [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] - specific message types:** Both time series ((% style="color:#e74c3c" %)version(%%) 2.0 Compact) and non-time series [[data sets>>doc:Glossary.Data set.WebHome]] ((% style="color:#e74c3c" %)version(%%) 2.0 Cross Sectional) use the same underlying structure for a structure-specific formatted message, which is specific to the [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] of the data set.
++* **Simplification of the [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] - specific message types:** Both time series (version 2.0 Compact) and non-time series [[data sets>>doc:Glossary.Data set.WebHome]] (version 2.0 Cross Sectional) use the same underlying structure for a structure-specific formatted message, which is specific to the [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] of the data set.
  * **Simplification and better support for the metadata structure: **New use cases have been reported and these are now supported by a re-modelled metadata structure definition.
  * **Web-Services-Oriented Changes:** Several organizations have been implementing web services applications using [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], and these implementations have resulted in several changes to the specifications. Because the nature of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] web services could not be anticipated at the time of the original drafting of the specifications, the web services guidelines have been completely re-developed.
  * **Presentational Changes: **Much work has gone into using various technologies for the visualization of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] data and metadata, and some changes have been proposed as a result, to better leverage this graphical visualization. These changes are largely to leverage the [[Cross-domain Concepts>>doc:Glossary.Cross-domain concept.WebHome]] of the Content Oriented Guidelines.
@@ -83,11 +83,11 @@
  * **Consistency between the [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] and the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]]: **Certain aspects of the XML schemas and UML model have been more closely aligned, to allow for easier comprehension of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] model.
  * **Technical Bugs:** Some minor technical bugs have been identified in the registry interfaces and elsewhere. These bugs have been addressed.
  * **Support for Non-Time-Series Data in the Generic Format: **One area which has been extended is the ability to express non-time-series data as part of the generic data message.
--* **Support for partial [[item schemes>>doc:Glossary.Item scheme.WebHome]] such as a [[code list>>doc:Glossary.Code list.WebHome]]: **The (% style="color:#e74c3c" %)concept(%%) of a partial (sub set) [[item scheme>>doc:Glossary.Item scheme.WebHome]] such as a partial [[code list>>doc:Glossary.Code list.WebHome]] for use in exchange scenarios has been introduced**.**
++* **Support for partial [[item schemes>>doc:Glossary.Item scheme.WebHome]] such as a [[code list>>doc:Glossary.Code list.WebHome]]: **The concept of a partial (sub set) [[item scheme>>doc:Glossary.Item scheme.WebHome]] such as a partial [[code list>>doc:Glossary.Code list.WebHome]] for use in exchange scenarios has been introduced**.**
  == 2.3 Major Changes from 2.1 to 3.0 ==
--[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)version(%%) 3.0 introduces new features, improvements and changes to the Standard in the following key areas:
++[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] version 3.0 introduces new features, improvements and changes to the Standard in the following key areas:
  (% class="wikigeneratedid" id="HInformationModel" %)
  **Information Model**
@@ -116,7 +116,7 @@
  (% class="wikigeneratedid" id="HSOAPWebServicesAPI" %)
  **SOAP Web Services API**
--* The SOAP web services API has been deprecated with (% style="color:#e74c3c" %)version(%%) 3.0 standardising on REST
++* The SOAP web services API has been deprecated with version 3.0 standardising on REST
  (% class="wikigeneratedid" id="HXML2CJSON2CCSVandEDITransmissionformats" %)
  **XML, JSON, CSV and EDI Transmission formats**
@@ -125,19 +125,19 @@
  * Obsolete [[SDMX-ML>>doc: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
  * The [[SDMX-EDI>>doc:Glossary.SDMX-EDI.WebHome]] transmission format for structures and data has been deprecated
  * The organisation of structures into ‘collections’ in [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:Glossary.SDMX-JSON.WebHome]] structure messages has been flattened and simplified
--* The option to reference structures in [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:Glossary.SDMX-JSON.WebHome]] messages using Agency, ID and (% style="color:#e74c3c" %)Version(%%) has been deprecated with URN now exclusively used for all non-local referencing purpose
++* The option to reference structures in [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] and [[SDMX-JSON>>doc:Glossary.SDMX-JSON.WebHome]] messages using Agency, ID and (% style="color:#e74c3c" %)[[Version>>doc:sdmx:Glossary.Version.WebHome]](%%) has been deprecated with URN now exclusively used for all non-local referencing purpose
--Several of the changes are ‘breaking’ meaning that, in specific cases, the (% style="color:#e74c3c" %)version(%%) 3.0 specification is not backwardly compatible with earlier (% style="color:#e74c3c" %)versions(%%) of the Standard.
++Several of the changes are ‘breaking’ meaning that, in specific cases, the version 3.0 specification is not backwardly compatible with earlier versions of the Standard.
  The principle breaking changes are:
  * REST API – 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.
--* SOAP API – Deprecation of the SOAP API means that existing systems designed to use SOAP will not work with (% style="color:#e74c3c" %)version(%%) 3.0 registries.
--* [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] – [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 and earlier structure, data and metadata XML messages are not valid in (% style="color:#e74c3c" %)version(%%) 3.0. Specifically: legacy data messages including Generic, Compact and Utility are no longer supported. The remaining Structure Specific data message has been changed to support new features such as reporting of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] as part of the [[dataset>>doc:Glossary.Data set.WebHome]], Structure messages have a number of breaking changes, principally modification to the information model, removal of the agency-(% style="color:#e74c3c" %)version(%%)-id option for referencing [[artefacts>>doc:Glossary.Artefact.WebHome]] and changes to the way the structures are organised into ‘collections’ within the message.
--* [[SDMX-JSON>>doc:Glossary.SDMX-JSON.WebHome]] – [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 structure, data and metadata JSON messages are not valid in (% style="color:#e74c3c" %)version(%%) 3.0. The data message has been changed to support the improved REST data queries, in particular the ability to retrieve in one operation data from multiple [[datasets>>doc:Glossary.Data set.WebHome]] with potentially different [[Data Structure Definitions>>doc:Glossary.Data structure definition.WebHome]]. Breaking changes similar to those for the [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] transmission format have been made to the structure message.
--* [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-CSV - The CSV data and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] messages are not backwardly compatible with those under (% style="color:#e74c3c" %)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.
--* [[SDMX-EDI>>doc:Glossary.SDMX-EDI.WebHome]] – Deprecation of the EDI transmission format means that existing systems designed to send or receive structures or data in EDI will not work with (% style="color:#e74c3c" %)version(%%) 3.0 registries.
--* Information Model – Several structures have been changed in the (% style="color:#e74c3c" %)version(%%) 3.0 model and three removed. For these reasons the (% style="color:#e74c3c" %)version(%%) 3.0 model is not directly compatible with (% style="color:#e74c3c" %)version(%%) 2.1 or earlier, although conversion of specific [[artefacts>>doc:Glossary.Artefact.WebHome]] is possible under some circumstances. Loss of information during the conversion process however means that in cases like structure mapping, the conversion is not reversible i.e. it is not possible to recreate the 2.1 structure once it has been converted to the 3.0 model.
++* SOAP API – Deprecation of the SOAP API means that existing systems designed to use SOAP will not work with version 3.0 registries.
++* [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] – [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 and earlier structure, data and metadata XML messages are not valid in version 3.0. Specifically: legacy data messages including Generic, Compact and Utility are no longer supported. The remaining Structure Specific data message has been changed to support new features such as reporting of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] as part of the [[dataset>>doc:Glossary.Data set.WebHome]], Structure messages have a number of breaking changes, principally modification to the information model, removal of the agency-version-id option for referencing [[artefacts>>doc:Glossary.Artefact.WebHome]] and changes to the way the structures are organised into ‘collections’ within the message.
++* [[SDMX-JSON>>doc:Glossary.SDMX-JSON.WebHome]] – [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 structure, data and metadata JSON messages are not valid in version 3.0. The data message has been changed to support the improved REST data queries, in particular the ability to retrieve in one operation data from multiple [[datasets>>doc:Glossary.Data set.WebHome]] with potentially different [[Data Structure Definitions>>doc:Glossary.Data structure definition.WebHome]]. Breaking changes similar to those for the [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] transmission format have been made to the structure message.
++* [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-CSV - The CSV data and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] messages are not backwardly compatible with those under 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.
++* [[SDMX-EDI>>doc:Glossary.SDMX-EDI.WebHome]] – Deprecation of the EDI transmission format means that existing systems designed to send or receive structures or data in EDI will not work with version 3.0 registries.
++* Information Model – Several structures have been changed in the version 3.0 model and three removed. For these reasons the version 3.0 model is not directly compatible with version 2.1 or earlier, although conversion of specific [[artefacts>>doc:Glossary.Artefact.WebHome]] is possible under some circumstances. Loss of information during the conversion process however means that in cases like structure mapping, the conversion is not reversible i.e. it is not possible to recreate the 2.1 structure once it has been converted to the 3.0 model.
  The [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 3.0 Major Changes document provides more information including an analysis of the breaking changes.
@@ -181,11 +181,11 @@
  == 3.3 Statistical Data and Metadata ==
--To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific (% style="color:#e74c3c" %)concepts(%%), which act as identifiers and descriptors of the data. These metadata values and (% style="color:#e74c3c" %)concepts(%%) can be understood as the named [[dimensions>>doc:Glossary.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
++To avoid confusion about which "data" and "metadata" are the intended content of the [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] formats specified here, a statement of scope is offered. Statistical "data" are sets of often numeric observations which typically have time associated with them. They are associated with a set of metadata values, representing specific (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%), which act as identifiers and descriptors of the data. These metadata values and (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) can be understood as the named [[dimensions>>doc:sdmx:Glossary.Dimension.WebHome]] of a multi-dimensional co-ordinate system, describing what is often called a "cube" of data.
--[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] identifies a standard technique for modelling, expressing, and understanding the structure of this multi-dimensional "cube", allowing automated processing of data from a variety of sources. This approach is widely applicable across types of data and attempts to provide the simplest and most easily comprehensible technique that will support the exchange of this broad set of data and related metadata.
++[[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] identifies a standard technique for modelling, expressing, and understanding the structure of this multi-dimensional "cube", allowing automated processing of data from a variety of sources. This approach is widely applicable across types of data and attempts to provide the simplest and most easily comprehensible technique that will support the exchange of this broad set of data and related metadata.
--The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those (% style="color:#e74c3c" %)concepts(%%) used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of (% style="color:#e74c3c" %)concepts(%%) that describe and qualify statistical [[data sets>>doc:Glossary.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or series of data, but with entire collections of data or even the institutions which provide that data.
++The term "metadata" is very broad indeed. A distinction can be made between “structural” metadata – those (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) used in the description and identification of statistical data and metadata – and “reference” metadata – the larger set of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) that describe and qualify statistical [[data sets>>doc:sdmx:Glossary.Data set.WebHome]] and processing more generally, and which are often associated not with specific observations or series of data, but with entire collections of data or even the institutions which provide that data.
  The [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] provides for the structuring not only of data, but also of “reference” metadata. While these [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structures exist independent of the data and its [[structural metadata>>doc:Glossary.Structural metadata.WebHome]], they are often linked. The [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] provides for the attachment of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] to any part of the data or [[structural metadata>>doc:Glossary.Structural metadata.WebHome]], as well as for the reporting and exchange of the [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] and its structural descriptions. This function of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] standards supports many aspects of data quality initiatives, allowing as it does for the exchange of metadata in its broadest sense, of which quality-related metadata is a major part.
@@ -203,42 +203,45 @@
  == 3.4 The SDMX View of Statistical Exchange ==
--(% style="color:#e74c3c" %)Version(%%) 1.0 of ISO/TS 17369 [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] covered statistical [[data sets>>doc:Glossary.Data set.WebHome]] and the metadata related to the structure of these [[data sets>>doc:Glossary.Data set.WebHome]]. This scope was useful in supporting the different models of statistical exchange (bilateral exchange, gateway exchange, and data-sharing) but was not by itself sufficient to support them completely. (% style="color:#e74c3c" %)Versions(%%) 2.0 and 2.1 provide a much more complete view of statistical exchange, so that an open data-sharing model can be fully supported, and other models of exchange can be more completely automated. In order to produce technical standards that will support this increased scope, the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] provides a broader set of formal objects which describe the actors, processes, and resources within statistical exchanges.
++Version 1.0 of ISO/TS 17369 [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] covered statistical [[data sets>>doc:Glossary.Data set.WebHome]] and the metadata related to the structure of these [[data sets>>doc:Glossary.Data set.WebHome]]. This scope was useful in supporting the different models of statistical exchange (bilateral exchange, gateway exchange, and data-sharing) but was not by itself sufficient to support them completely. Versions 2.0 and 2.1 provide a much more complete view of statistical exchange, so that an open data-sharing model can be fully supported, and other models of exchange can be more completely automated. In order to produce technical standards that will support this increased scope, the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] provides a broader set of formal objects which describe the actors, processes, and resources within statistical exchanges.
  It is important to understand the set of formal objects not only in a technical sense, but also in terms of what they represent in the real-world exchange of statistical data and metadata.
--The first (% style="color:#e74c3c" %)version(%%) of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provided for [[data sets>>doc:Glossary.Data set.WebHome]] - specific statistical data reported according to a specific structure, for a specific time range - and for [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] - the metadata which describes the structure of statistical [[data sets>>doc:Glossary.Data set.WebHome]]. These are important objects in statistical exchanges, and are retained and enhanced in the second (% style="color:#e74c3c" %)version(%%) of the standards in a backward-compatible form. A related object in statistical exchanges is the [[data flow>>doc:Glossary.Dataflow.WebHome]] - this supports the (% style="color:#e74c3c" %)concept(%%) of data reporting or dissemination on an ongoing basis. [[Data flows>>doc:Glossary.Dataflow.WebHome]] can be understood as [[data sets>>doc:Glossary.Data set.WebHome]] which are not bounded by time. Data structures are owned and maintained by agencies - in a similar fashion, [[data flows>>doc:Glossary.Dataflow.WebHome]] are owned by maintenance agencies.
++The first version of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provided for [[data sets>>doc:Glossary.Data set.WebHome]] - specific statistical data reported according to a specific structure, for a specific time range - and for [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] - the metadata which describes the structure of statistical [[data sets>>doc:Glossary.Data set.WebHome]]. These are important objects in statistical exchanges, and are retained and enhanced in the second version of the standards in a backward-compatible form. A related object in statistical exchanges is the [[data flow>>doc:Glossary.Dataflow.WebHome]] - this supports the concept of data reporting or dissemination on an ongoing basis. [[Data flows>>doc:Glossary.Dataflow.WebHome]] can be understood as [[data sets>>doc:Glossary.Data set.WebHome]] which are not bounded by time. Data structures are owned and maintained by agencies - in a similar fashion, [[data flows>>doc:Glossary.Dataflow.WebHome]] are owned by maintenance agencies.
--[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] allows for the publication of statistical data (and the related [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]) but also provided for the standard, systematic [[representation>>doc:Glossary.Representation.WebHome]] of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]]. In (% style="color:#e74c3c" %)version(%%) 2.1, [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] were reported independent of the statistical data. However, in 3.0 [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] associated directly with data such as footnotes are reported as [[attributes>>doc:Glossary.Attribute.WebHome]] of the [[data set>>doc:Glossary.Data set.WebHome]]. For other [[reference metadata>>doc:Glossary.Reference metadata.WebHome]], principally that linked to structures like “(% style="color:#e74c3c" %)concepts(%%)”, [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provides reference [[metadata sets>>doc:Glossary.Metadata set.WebHome]]", [[metadata structure definitions>>doc:Glossary.Metadata structure definition.WebHome]]", and [[metadata flows>>doc:Glossary.Metadataflow.WebHome]]". These objects are very similar to [[data sets>>doc:Glossary.Data set.WebHome]], [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]], and [[data flows>>doc:Glossary.Dataflow.WebHome]], but concern [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] rather than statistical observations. In the same way that [[data providers>>doc:Glossary.Data provider.WebHome]] may publish statistical data, they may also publish [[reference metadata>>doc:Glossary.Reference metadata.WebHome]]. Metadata structural definitions are maintained by agencies in a fashion similar to the way that agencies maintain [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]], the structural definitions of [[data sets>>doc:Glossary.Data set.WebHome]].
++[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] allows for the publication of statistical data (and the related [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]) but also provided for the standard, systematic [[representation>>doc:Glossary.Representation.WebHome]] of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]]. In version 2.1, [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] were reported independent of the statistical data. However, in 3.0 [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] associated directly with data such as footnotes are reported as [[attributes>>doc:Glossary.Attribute.WebHome]] of the [[data set>>doc:Glossary.Data set.WebHome]]. For other [[reference metadata>>doc:Glossary.Reference metadata.WebHome]], principally that linked to structures like “
--The structural definitions of both data and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] associate specific statistical (% style="color:#e74c3c" %)concepts(%%) with their [[representations>>doc:Glossary.Representation.WebHome]], whether textual, coded, etc. These (% style="color:#e74c3c" %)concepts(%%) are taken from a [[concept scheme>>doc:Glossary.Concept scheme.WebHome]] which is maintained by a specific agency. [[Concept schemes>>doc:Glossary.Concept scheme.WebHome]] group a set of (% style="color:#e74c3c" %)concepts(%%), provide their definitions and names, and allow for semantic relationships to be expressed, when some (% style="color:#e74c3c" %)concepts(%%) are specializations of others. It is possible for a single [[concept scheme>>doc:Glossary.Concept scheme.WebHome]] to be used both for data structures - key families - and for [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structures.
++(% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%)”, [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] provides [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] sets", [[metadata structure definitions>>doc:sdmx:Glossary.Metadata structure definition.WebHome]]", and [[metadata flows>>doc:sdmx:Glossary.Metadataflow.WebHome]]". These objects are very similar to [[data sets>>doc:sdmx:Glossary.Data set.WebHome]], [[data structure definitions>>doc:sdmx:Glossary.Data structure definition.WebHome]], and [[data flows>>doc:sdmx:Glossary.Dataflow.WebHome]], but concern [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] rather than statistical observations. In the same way that [[data providers>>doc:sdmx:Glossary.Data provider.WebHome]] may publish statistical data, they may also publish [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]]. Metadata structural definitions are maintained by agencies in a fashion similar to the way that agencies maintain [[data structure definitions>>doc:sdmx:Glossary.Data structure definition.WebHome]], the structural definitions of [[data sets>>doc:sdmx:Glossary.Data set.WebHome]].
--Inherent in any statistical exchange – and in many dissemination activities – is a (% style="color:#e74c3c" %)concept(%%) of "service (% style="color:#e74c3c" %)level(%%) agreement", even if this is not formalized or made explicit. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] incorporates this idea in objects termed [[provision agreements>>doc:Glossary.Provision agreement.WebHome]]". [[Data providers>>doc:Glossary.Data provider.WebHome]] may provide data to many different [[data flows>>doc:Glossary.Dataflow.WebHome]]. [[Data flows>>doc:Glossary.Dataflow.WebHome]] may incorporate data coming from more than one [[data provider>>doc:Glossary.Data provider.WebHome]]. [[Provision agreements>>doc:Glossary.Provision agreement.WebHome]] are the objects which tell you which [[data providers>>doc:Glossary.Data provider.WebHome]] are supplying what data to which [[data flows>>doc:Glossary.Dataflow.WebHome]]. Similarly, metadata [[provision agreements>>doc:Glossary.Provision agreement.WebHome]] for [[metadata flows>>doc:Glossary.Metadataflow.WebHome]].
++The structural definitions of both data and [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] associate specific statistical (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) with their [[representations>>doc:sdmx:Glossary.Representation.WebHome]], whether textual, coded, etc. These (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) are taken from a [[concept scheme>>doc:sdmx:Glossary.Concept scheme.WebHome]] which is maintained by a specific agency. [[Concept schemes>>doc:sdmx:Glossary.Concept scheme.WebHome]] group a set of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%), provide their definitions and names, and allow for semantic relationships to be expressed, when some (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) are specializations of others. It is possible for a single [[concept scheme>>doc:sdmx:Glossary.Concept scheme.WebHome]] to be used both for data structures - key families - and for [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] structures.
--[[Provision agreements>>doc:Glossary.Provision agreement.WebHome]] allow for a variety of information to be made available: the schedule by which statistical data or metadata is reported or published, the specific topics about which data or metadata is reported within the theoretically possible set of data (as described by a [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] or [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structure definition), and the [[time period>>doc:Glossary.Time period.WebHome]] covered by the statistical data and metadata. This set of information is termed (% style="color:#e74c3c" %)constraint(%%) in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]].
++Inherent in any statistical exchange – and in many dissemination activities – is a concept of "service level agreement", even if this is not formalized or made explicit. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] incorporates this idea in objects termed [[provision agreements>>doc:Glossary.Provision agreement.WebHome]]". [[Data providers>>doc:Glossary.Data provider.WebHome]] may provide data to many different [[data flows>>doc:Glossary.Dataflow.WebHome]]. [[Data flows>>doc:Glossary.Dataflow.WebHome]] may incorporate data coming from more than one [[data provider>>doc:Glossary.Data provider.WebHome]]. [[Provision agreements>>doc:Glossary.Provision agreement.WebHome]] are the objects which tell you which [[data providers>>doc:Glossary.Data provider.WebHome]] are supplying what data to which [[data flows>>doc:Glossary.Dataflow.WebHome]]. Similarly, metadata [[provision agreements>>doc:Glossary.Provision agreement.WebHome]] for [[metadata flows>>doc:Glossary.Metadataflow.WebHome]].
++[[Provision agreements>>doc:Glossary.Provision agreement.WebHome]] allow for a variety of information to be made available: the schedule by which statistical data or metadata is reported or published, the specific topics about which data or metadata is reported within the theoretically possible set of data (as described by a [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] or [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structure definition), and the [[time period>>doc:Glossary.Time period.WebHome]] covered by the statistical data and metadata. This set of information is termed (% style="color:#e74c3c" %)[[constraint>>doc:sdmx:Glossary.Constraint.WebHome]](%%) in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]].
++
  A brief summary of the objects described in the information model includes:
  * //**[[Data Set>>doc:Glossary.Data set.WebHome]]:**// Data is organized into discrete sets, which include particular observations for a specific period of time. A [[data set>>doc:Glossary.Data set.WebHome]] can be understood as a collection of similar data, sharing a structure, which covers a fixed period of time.
--* //**[[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] ([[DSD>>doc:Glossary.Data structure definition.WebHome]], also known as Key Family in (% style="color:#e74c3c" %)Version(%%) 2.0): **//Each [[data set>>doc:Glossary.Data set.WebHome]] has a set of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. These descriptions are referred to in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] as [[Data Structure Definitions>>doc:Glossary.Data structure definition.WebHome]], which include information about how (% style="color:#e74c3c" %)concepts(%%) are associated with the [[measures>>doc:Glossary.Measure.WebHome]], [[dimensions>>doc:Glossary.Dimension.WebHome]], and [[attributes>>doc:Glossary.Attribute.WebHome]] of a data “cube,” along with information about the [[representation>>doc:Glossary.Representation.WebHome]] of data and related identifying and descriptive (structural) metadata. In (% style="color:#e74c3c" %)Version(%%) 2.1, the term "Key Family" was replaced by [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] ([[DSD>>doc:Glossary.Data structure definition.WebHome]]) both in XML Schemas and the Information Model. The [[DSD>>doc:Glossary.Data structure definition.WebHome]] has been modified in (% style="color:#e74c3c" %)version(%%) 3.0 to better support microdata by providing the option to define multiple [[measures>>doc:Glossary.Measure.WebHome]] and for [[attributes>>doc:Glossary.Attribute.WebHome]] and [[measures>>doc:Glossary.Measure.WebHome]] to take arrays of values. An optional reference to a [[Metadata Structure Definition>>doc:Glossary.Metadata structure definition.WebHome]] has also been added for describing the [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] associated with the data. When reported, these [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] are included as part of the dataset.
++* //**[[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] ([[DSD>>doc:Glossary.Data structure definition.WebHome]], also known as Key Family in Version 2.0): **//Each [[data set>>doc:Glossary.Data set.WebHome]] has a set of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. These descriptions are referred to in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] as [[Data Structure Definitions>>doc:Glossary.Data structure definition.WebHome]], which include information about how [[concepts>>doc:sdmx:Glossary.Concept.WebHome]] are associated with the [[measures>>doc:Glossary.Measure.WebHome]], [[dimensions>>doc:Glossary.Dimension.WebHome]], and [[attributes>>doc:Glossary.Attribute.WebHome]] of a data “cube,” along with information about the [[representation>>doc:Glossary.Representation.WebHome]] of data and related identifying and descriptive (structural) metadata. In Version 2.1, the term "Key Family" was replaced by [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] ([[DSD>>doc:Glossary.Data structure definition.WebHome]]) both in XML Schemas and the Information Model. The [[DSD>>doc:Glossary.Data structure definition.WebHome]] has been modified in version 3.0 to better support microdata by providing the option to define multiple [[measures>>doc:Glossary.Measure.WebHome]] and for [[attributes>>doc:Glossary.Attribute.WebHome]] and [[measures>>doc:Glossary.Measure.WebHome]] to take arrays of values. An optional reference to a [[Metadata Structure Definition>>doc:Glossary.Metadata structure definition.WebHome]] has also been added for describing the [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] associated with the data. When reported, these [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] are included as part of the dataset.
  * //**[[Code list>>doc:Glossary.Code list.WebHome]]:**// [[Code lists>>doc:Glossary.Code list.WebHome]] enumerate a set of [[codes>>doc:Glossary.Code.WebHome]] to be used in the [[representation>>doc:Glossary.Representation.WebHome]] of [[dimensions>>doc:Glossary.Dimension.WebHome]], [[attributes>>doc:Glossary.Attribute.WebHome]], and other structural parts of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]. [[Codes>>doc:Glossary.Code.WebHome]] can be organised into simple [[hierarchies>>doc:Glossary.Hierarchy.WebHome]] within a [[code list>>doc:Glossary.Code list.WebHome]], and more complex [[hierarchies>>doc:Glossary.Hierarchy.WebHome]] potentially involving multiple [[code lists>>doc:Glossary.Code list.WebHome]] using [[hierarchy>>doc:Glossary.Hierarchy.WebHome]] and [[hierarchy>>doc:Glossary.Hierarchy.WebHome]] association structures.
--* //**Value list:**// Value lists introduced in (% style="color:#e74c3c" %)version(%%) 3.0 are similar to codelists with the exception that the items do not need to conform to the usual [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] rules for identifiable objects. That allows the values to include characters such as [[currency>>doc:Glossary.Currency.WebHome]] symbols (e.g. ¥) which would otherwise make illegal [[codes>>doc:Glossary.Code.WebHome]]. However, unlike [[codes>>doc:Glossary.Code.WebHome]], values are not individually identifiable. Value lists find application in (% style="color:#e74c3c" %)concepts(%%) and [[data structures definitions>>doc:Glossary.Data structure definition.WebHome]] for less structured data and microdata enumerations and can be (% style="color:#e74c3c" %)mapped(%%) to other value or [[code lists>>doc:Glossary.Code list.WebHome]] using [[representation>>doc:Glossary.Representation.WebHome]] (% style="color:#e74c3c" %)maps(%%).
++* //**Value list:**// Value lists introduced in version 3.0 are similar to [[codelists>>doc:sdmx:Glossary.Code list.WebHome]] with the exception that the items do not need to conform to the usual [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] rules for identifiable objects. That allows the values to include characters such as [[currency>>doc:Glossary.Currency.WebHome]] symbols (e.g. ¥) which would otherwise make illegal [[codes>>doc:Glossary.Code.WebHome]]. However, unlike [[codes>>doc:Glossary.Code.WebHome]], values are not individually identifiable. Value lists find application in [[concepts>>doc:sdmx:Glossary.Concept.WebHome]] and [[data structures definitions>>doc:Glossary.Data structure definition.WebHome]] for less structured data and microdata enumerations and can be mapped to other value or [[code lists>>doc:Glossary.Code list.WebHome]] using [[representation>>doc:Glossary.Representation.WebHome]] maps.
  * //**Organisation Scheme:**// Organisations and organisation structure can be defined in an Organisation Scheme. Specific Organisation Schemes exist for [[Maintenance Agency>>doc:Glossary.Maintenance agency.WebHome]], [[Data Provider>>doc:Glossary.Data provider.WebHome]], Metadata Provider, [[Data Consumer>>doc:Glossary.Data consumer.WebHome]], and Organisation Unit.
  * //**[[Category Scheme>>doc:Glossary.Category scheme.WebHome]] and Categorisation:**// [[Category schemes>>doc:Glossary.Category scheme.WebHome]] are made up of a [[hierarchy>>doc:Glossary.Hierarchy.WebHome]] of [[categories>>doc:Glossary.Category.WebHome]], which in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] may include any type of useful classification for the organization of data and metadata. A Categorisation links a [[category>>doc:Glossary.Category.WebHome]] to an identifiable object. In this way sets of objects can be categorised. A statistical subjectmatter domain scheme is implemented in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] as a [[Category Scheme>>doc:Glossary.Category scheme.WebHome]].
--* //**[[Concept Scheme>>doc:Glossary.Concept scheme.WebHome]]:**// A [[concept scheme>>doc:Glossary.Concept scheme.WebHome]] is a maintained list of (% style="color:#e74c3c" %)concepts(%%) that are used in [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] and [[metadata structure definitions>>doc:Glossary.Metadata structure definition.WebHome]]. There can be many such [[concept schemes>>doc:Glossary.Concept scheme.WebHome]]. A “core” [[representation>>doc:Glossary.Representation.WebHome]] of the (% style="color:#e74c3c" %)concept(%%) can be specified (e.g. a core [[code list>>doc:Glossary.Code list.WebHome]], or other [[representation>>doc:Glossary.Representation.WebHome]] such as “date”). Note that this core [[representation>>doc:Glossary.Representation.WebHome]] can be overridden in the [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] or [[metadata structure definition>>doc:Glossary.Metadata structure definition.WebHome]] that uses the (% style="color:#e74c3c" %)concept(%%). Indeed, organisations wishing to remain with (% style="color:#e74c3c" %)version(%%) 1.0 key family schema specifications will continue to declare the [[representation>>doc:Glossary.Representation.WebHome]] in the key family definition.
--* //**[[Metadata Set>>doc:Glossary.Metadata set.WebHome]]:**// A [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] set is a set of information pertaining to an object within the formal [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] view of statistical exchange: they may describe the maintainers of data or structural definitions; they may describe the schedule on which data is released; they may describe the flow of a single type of data over time; they may describe the quality of data, etc. In [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], the creators of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] may take whatever (% style="color:#e74c3c" %)concepts(%%) they are concerned with, or obliged to report, and provide a [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] set containing that information.
--* //**[[Metadata Structure Definition>>doc:Glossary.Metadata structure definition.WebHome]]:**// A [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] set also has a set of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] which describes how it is organized. This [[metadata set>>doc:Glossary.Metadata set.WebHome]] identifies what [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] (% style="color:#e74c3c" %)concepts(%%) are being reported, how these (% style="color:#e74c3c" %)concepts(%%) relate to each other (typically as [[hierarchies>>doc:Glossary.Hierarchy.WebHome]]), what their presentational structure is, how they may be represented (as free text, as coded values, etc.), and with which formal [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] object types they are associated.
--* //**[[Dataflow>>doc:Glossary.Dataflow.WebHome]] Definition:**// In [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], [[data sets>>doc:Glossary.Data set.WebHome]] are reported or disseminated according to a [[data flow>>doc:Glossary.Dataflow.WebHome]] definition. The [[data flow>>doc:Glossary.Dataflow.WebHome]] definition identifies the [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] and may be associated with one or more subject matter domains via a Categorisation (this facilitates the search for data according to organised [[category schemes>>doc:Glossary.Category scheme.WebHome]]). (% style="color:#e74c3c" %)Constraints(%%), in terms of reporting periodicity or sub set of possible keys that are allowed in a [[data set>>doc:Glossary.Data set.WebHome]], may be attached to the [[data flow>>doc:Glossary.Dataflow.WebHome]] definition.
--* //**Metadataflow Definition:**// A [[metadata flow>>doc:Glossary.Metadataflow.WebHome]] definition is very similar to a [[data flow>>doc:Glossary.Dataflow.WebHome]] definition, but describes, categorises, and constrains [[metadata sets>>doc:Glossary.Metadata set.WebHome]].
--* //**[[Data Provider>>doc:Glossary.Data provider.WebHome]]: **//An organization which produces data is termed a [[data provider>>doc:Glossary.Data provider.WebHome]].
--* //**Metadata Provider: **//An organization which produces [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] is termed a metadata provider.
--* //**[[Provision Agreement>>doc:Glossary.Provision agreement.WebHome]] (Metadata [[Provision Agreement>>doc:Glossary.Provision agreement.WebHome]]):**// The set of information which describes the way in which [[data sets>>doc:Glossary.Data set.WebHome]] and [[metadata sets>>doc:Glossary.Metadata set.WebHome]] are provided by a data/metadata provider. A [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] can be constrained in much the same way as a data or [[metadata flow>>doc:Glossary.Metadataflow.WebHome]] definition. Thus, a [[data provider>>doc:Glossary.Data provider.WebHome]] can express the fact that it provides a particular [[data flow>>doc:Glossary.Dataflow.WebHome]] covering a specific set of countries and topics, Importantly, the actual source of registered data or metadata is attached to the [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] (in terms of a URL). The term “agreement” is used because this information can be understood as the basis of a “service-(% style="color:#e74c3c" %)level(%%) agreement”. In [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], however, this is informational metadata to support the technical systems, as opposed to any sort of contractual information (which is outside the scope of a technical specification). In (% style="color:#e74c3c" %)version(%%) 3.0, metadata [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] and data [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] are two separate [[artefacts>>doc:Glossary.Artefact.WebHome]].
--* (% style="color:#e74c3c" %)//**Constraint**//(%%)//**:**// Data and Metadata (% style="color:#e74c3c" %)Constraints(%%) describe a subset of a [[data source>>doc:Glossary.Data source.WebHome]] or metadata source, and may also provide information about scheduled releases of data. They are associated with data / metadata providers, [[provision agreements>>doc:Glossary.Provision agreement.WebHome]], [[data flows>>doc:Glossary.Dataflow.WebHome]], [[metadataflows>>doc:Glossary.Metadataflow.WebHome]], [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] and [[metadata structure definitions>>doc:Glossary.Metadata structure definition.WebHome]].
--* //**Structure (% style="color:#e74c3c" %)Map(%%): **//Structure (% style="color:#e74c3c" %)maps(%%) describes a mapping between [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] or [[dataflows>>doc:Glossary.Dataflow.WebHome]] for the purpose of transforming a [[data set>>doc:Glossary.Data set.WebHome]] into a different structure. The mapping rules are defined using one or more [[component>>doc:Glossary.Component.WebHome]] (% style="color:#e74c3c" %)maps(%%) which each (% style="color:#e74c3c" %)map(%%) in turn describes how one or more [[components>>doc:Glossary.Component.WebHome]] from the source data 534 structure definition (% style="color:#e74c3c" %)map(%%) to one or more [[components>>doc:Glossary.Component.WebHome]] in that of the target. Represent (% style="color:#e74c3c" %)maps(%%) act as lookup tables and specific provision is made for mapping dates and times.
--* //**[[Representation>>doc:Glossary.Representation.WebHome]] (% style="color:#e74c3c" %)Map(%%):**// [[Representation>>doc:Glossary.Representation.WebHome]] (% style="color:#e74c3c" %)maps(%%) describe mappings between source value(s) and target value(s) where the values are restricted to those in a [[code list>>doc:Glossary.Code list.WebHome]], value list or be of a certain type such as integer or string.
--* //**[[Item Scheme>>doc:Glossary.Item scheme.WebHome]] (% style="color:#e74c3c" %)Map(%%):**// An [[item scheme>>doc:Glossary.Item scheme.WebHome]] (% style="color:#e74c3c" %)map(%%) describes mapping rules between any [[item scheme>>doc:Glossary.Item scheme.WebHome]] with the exception of [[code lists>>doc:Glossary.Code list.WebHome]] and value lists which use [[representation>>doc:Glossary.Representation.WebHome]] (% style="color:#e74c3c" %)maps(%%). The (% style="color:#e74c3c" %)version(%%) 3.0 information model provides four [[item scheme>>doc:Glossary.Item scheme.WebHome]] (% style="color:#e74c3c" %)maps(%%): organisation scheme (% style="color:#e74c3c" %)map(%%), [[concept scheme>>doc:Glossary.Concept scheme.WebHome]] (% style="color:#e74c3c" %)map(%%), [[category scheme>>doc:Glossary.Category scheme.WebHome]] (% style="color:#e74c3c" %)map(%%) and [[reporting taxonomy>>doc:Glossary.Reporting taxonomy.WebHome]] (% style="color:#e74c3c" %)map(%%). Organisation scheme (% style="color:#e74c3c" %)map(%%) and reporting scheme (% style="color:#e74c3c" %)map(%%) have been omitted from the information model schematic in Figure 1.
++* //**[[Concept Scheme>>doc:Glossary.Concept scheme.WebHome]]:**// A [[concept scheme>>doc:sdmx:Glossary.Concept scheme.WebHome]] is a maintained list of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) that are used in [[data structure definitions>>doc:sdmx:Glossary.Data structure definition.WebHome]] and [[metadata structure definitions>>doc:sdmx:Glossary.Metadata structure definition.WebHome]]. There can be many such [[concept schemes>>doc:sdmx:Glossary.Concept scheme.WebHome]]. A “core” [[representation>>doc:sdmx:Glossary.Representation.WebHome]] of the (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) can be specified (e.g. a core [[code list>>doc:sdmx:Glossary.Code list.WebHome]], or other [[representation>>doc:sdmx:Glossary.Representation.WebHome]] such as “date”). Note that this core [[representation>>doc:sdmx:Glossary.Representation.WebHome]] can be overridden in the [[data structure definition>>doc:sdmx:Glossary.Data structure definition.WebHome]] or [[metadata structure definition>>doc:sdmx:Glossary.Metadata structure definition.WebHome]] that uses the (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%). Indeed, organisations wishing to remain with version 1.0 key family schema specifications will continue to declare the [[representation>>doc:Glossary.Representation.WebHome]] in the key family definition.
++* //**[[Metadata Set>>doc:Glossary.Metadata set.WebHome]]:**// A [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] set is a set of information pertaining to an object within the formal [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] view of statistical exchange: they may describe the maintainers of data or structural definitions; they may describe the schedule on which data is released; they may describe the flow of a single type of data over time; they may describe the quality of data, etc. In [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], the creators of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] may take whatever
++* (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) they are concerned with, or obliged to report, and provide a [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] set containing that information.
++* //**Metadata Structure Definition:**// A [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] set also has a set of [[structural metadata>>doc:sdmx:Glossary.Structural metadata.WebHome]] which describes how it is organized. This [[metadata set>>doc:sdmx:Glossary.Metadata set.WebHome]] identifies what [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) are being reported, how these (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) relate to each other (typically as [[hierarchies>>doc:sdmx:Glossary.Hierarchy.WebHome]]), what their presentational structure is, how they may be represented (as free text, as coded values, etc.), and with which formal [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] object types they are associated.
++* //**Dataflow Definition:**// In [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]], [[data sets>>doc:sdmx:Glossary.Data set.WebHome]] are reported or disseminated according to a [[data flow>>doc:sdmx:Glossary.Dataflow.WebHome]] definition. The [[data flow>>doc:sdmx:Glossary.Dataflow.WebHome]] definition identifies the [[data structure definition>>doc:sdmx:Glossary.Data structure definition.WebHome]] and may be associated with one or more subject matter domains via a Categorisation (this facilitates the search for data according to organised [[category schemes>>doc:sdmx:Glossary.Category scheme.WebHome]]). (% style="color:#e74c3c" %)[[Constraints>>doc:sdmx:Glossary.Constraint.WebHome]](%%), in terms of reporting periodicity or sub set of possible keys that are allowed in a [[data set>>doc:sdmx:Glossary.Data set.WebHome]], may be attached to the [[data flow>>doc:sdmx:Glossary.Dataflow.WebHome]] definition.
++* //**Metadataflow Definition:**// A [[metadata flow>>doc:sdmx:Glossary.Metadataflow.WebHome]] definition is very similar to a [[data flow>>doc:sdmx:Glossary.Dataflow.WebHome]] definition, but describes, categorises, and constrains metadata sets.
++* //**Data Provider: **//An organization which produces data is termed a data provider.
++* //**Metadata Provider: **//An organization which produces [[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]] is termed a metadata provider.
++* //**[[Provision Agreement>>doc:Glossary.Provision agreement.WebHome]] (Metadata [[Provision Agreement>>doc:Glossary.Provision agreement.WebHome]]):**// The set of information which describes the way in which [[data sets>>doc:Glossary.Data set.WebHome]] and [[metadata sets>>doc:Glossary.Metadata set.WebHome]] are provided by a data/metadata provider. A [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] can be constrained in much the same way as a data or [[metadata flow>>doc:Glossary.Metadataflow.WebHome]] definition. Thus, a [[data provider>>doc:Glossary.Data provider.WebHome]] can express the fact that it provides a particular [[data flow>>doc:Glossary.Dataflow.WebHome]] covering a specific set of countries and topics, Importantly, the actual source of registered data or metadata is attached to the [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] (in terms of a URL). The term “agreement” is used because this information can be understood as the basis of a “service-level agreement”. In [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]], however, this is informational metadata to support the technical systems, as opposed to any sort of contractual information (which is outside the scope of a technical specification). In version 3.0, metadata [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] and data [[provision agreement>>doc:Glossary.Provision agreement.WebHome]] are two separate [[artefacts>>doc:Glossary.Artefact.WebHome]].
++* (% style="color:#e74c3c" %)//**[[Constraint>>doc:sdmx:Glossary.Constraint.WebHome]]**//(%%)//**:**// Data and Metadata (% style="color:#e74c3c" %)[[Constraints>>doc:sdmx:Glossary.Constraint.WebHome]](%%) describe a subset of a [[data source>>doc:sdmx:Glossary.Data source.WebHome]] or metadata source, and may also provide information about scheduled releases of data. They are associated with data / metadata providers, [[provision agreements>>doc:sdmx:Glossary.Provision agreement.WebHome]], [[data flows>>doc:sdmx:Glossary.Dataflow.WebHome]], [[metadataflows>>doc:sdmx:Glossary.Metadataflow.WebHome]], [[data structure definitions>>doc:sdmx:Glossary.Data structure definition.WebHome]] and [[metadata structure definitions>>doc:sdmx:Glossary.Metadata structure definition.WebHome]].
++* //**Structure Map: **//Structure maps describes a mapping between [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] or [[dataflows>>doc:Glossary.Dataflow.WebHome]] for the purpose of transforming a [[data set>>doc:Glossary.Data set.WebHome]] into a different structure. The mapping rules are defined using one or more [[component>>doc:Glossary.Component.WebHome]] [[maps>>doc:sdmx:Glossary.Map.WebHome]] which each [[map>>doc:sdmx:Glossary.Map.WebHome]] in turn describes how one or more [[components>>doc:Glossary.Component.WebHome]] from the source data 534 structure definition map to one or more [[components>>doc:Glossary.Component.WebHome]] in that of the target. Represent maps act as lookup tables and specific provision is made for mapping dates and times.
++* //**[[Representation>>doc:Glossary.Representation.WebHome]] Map:**// [[Representation>>doc:Glossary.Representation.WebHome]] maps describe mappings between source value(s) and target value(s) where the values are restricted to those in a [[code list>>doc:Glossary.Code list.WebHome]], value list or be of a certain type such as integer or string.
++* //**[[Item Scheme>>doc:Glossary.Item scheme.WebHome]] Map:**// An [[item scheme>>doc:Glossary.Item scheme.WebHome]] map describes mapping rules between any [[item scheme>>doc:Glossary.Item scheme.WebHome]] with the exception of [[code lists>>doc:Glossary.Code list.WebHome]] and value lists which use [[representation>>doc:Glossary.Representation.WebHome]] maps. The version 3.0 information model provides four [[item scheme>>doc:Glossary.Item scheme.WebHome]] maps: organisation scheme map, [[concept scheme>>doc:Glossary.Concept scheme.WebHome]] map, [[category scheme>>doc:Glossary.Category scheme.WebHome]] map and [[reporting taxonomy>>doc:Glossary.Reporting taxonomy.WebHome]] map. Organisation scheme map and reporting scheme map have been omitted from the information model schematic in Figure 1.
  * //**[[Reporting Taxonomy>>doc:Glossary.Reporting taxonomy.WebHome]]: **//A [[reporting taxonomy>>doc:Glossary.Reporting taxonomy.WebHome]] allows an organisation to link (possibly in a hierarchical way) a number of cube or [[data flow>>doc:Glossary.Dataflow.WebHome]] definitions which together form a complete “report” of data or metadata. This supports primary reporting which often comprises multiple cubes of heterogeneous data, but may also support other collection and reporting functions. It also supports the specification of publications such as a yearbook, in terms of the data or metadata contained in the publication.
--* //**Process:**// The process class provides a way to model statistical processes as a set of interconnected //process steps.// Although not central to the exchange and dissemination of statistical data and metadata, having a shared description of processing allows for the interoperable exchange and dissemination of reference 556 [[metadata sets>>doc:Glossary.Metadata set.WebHome]] which describe processes-related (% style="color:#e74c3c" %)concepts(%%).
++* //**Process:**// The process class provides a way to model statistical processes as a set of interconnected //process steps.// Although not central to the exchange and dissemination of statistical data and metadata, having a shared description of processing allows for the interoperable exchange and dissemination of reference 556 [[metadata sets>>doc:Glossary.Metadata set.WebHome]] which describe processes-related (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%).
  * //**[[Hierarchy>>doc:Glossary.Hierarchy.WebHome]]**//: Describes complex [[code>>doc:Glossary.Code.WebHome]] [[hierarchies>>doc:Glossary.Hierarchy.WebHome]] principally for data discovery purposes. The [[codes>>doc:Glossary.Code.WebHome]] themselves are referenced from the [[code lists>>doc:Glossary.Code list.WebHome]] in which they are maintained.
  * //**[[Hierarchy>>doc:Glossary.Hierarchy.WebHome]] Association**//: A [[hierarchy>>doc:Glossary.Hierarchy.WebHome]] association links a [[hierarchy>>doc:Glossary.Hierarchy.WebHome]] to something that needs it like a [[dimension>>doc:Glossary.Dimension.WebHome]]. Furthermore, the linking can be specified in the context of another object such as a [[dimension>>doc:Glossary.Dimension.WebHome]] in the context of a [[dataflow>>doc:Glossary.Dataflow.WebHome]]. Thus, a [[dimension>>doc:Glossary.Dimension.WebHome]] in a [[data structure definition>>doc:Glossary.Data structure definition.WebHome]] could have different [[hierarchies>>doc:Glossary.Hierarchy.WebHome]] depending on the [[dataflow>>doc:Glossary.Dataflow.WebHome]].
  * //**Transformation Scheme:**// A transformation scheme is a set of [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]]) transformations aimed at obtaining some meaningful results for the user (e.g., the validation of one or more [[data sets>>doc:Glossary.Data set.WebHome]]). The set of transformations is meant to be executed together (in the same run) and may contain any number of transformations in order to produce any number of results. Thus, a transformation scheme can be considered as a [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] ‘program’.
@@ -262,7 +262,7 @@
  Web services allow computer applications to exchange data directly over the Internet, essentially allowing modular or distributed computing in a more flexible fashion than ever before. In order to allow web services to function, however, many standards are required: for requesting and supplying data; for expressing the enveloping data which is used to package exchanged data; for describing web services to one another, to allow for easy integration into applications that use other web services as data resources.
--(% style="color:#e74c3c" %)Version(%%) 3.0 has standardized on RESTful web services with a OpenAPI specification published on the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Working Group’s GitHub repository [[__https:~~/~~/github.com/sdmx-twg__>>https://https:github.comsdmx-twg]]. There are five ‘resources’:
++Version 3.0 has standardized on RESTful web services with a OpenAPI specification published on the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Working Group’s GitHub repository [[__https:~~/~~/github.com/sdmx-twg__>>https://github.comsdmx-twg]]. There are five ‘resources’:
  * structure – retrieval and maintenance of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]
  * data – retrieval of data
@@ -278,15 +278,15 @@
  [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provides a way of modelling statistical data, and defines the set of metadata constructs used for this purpose. Because [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] specifies a number of transmission formats for expressing data and [[structural metadata>>doc:Glossary.Structural metadata.WebHome]], the model is used as a mechanism for guaranteeing that transformation between the different formats is lossless. In this sense, all of the formats are syntax-bound expressions of the common information model.
--[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] recognizes that statistical data is structured; in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] this structure is termed a [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]]. “[[Data sets>>doc:Glossary.Data set.WebHome]]” are made up of one or more lower-(% style="color:#e74c3c" %)level(%%) “groups”, based on their degrees of similarity. Each group is in turn comprised of one or more “series” of data. Each series or section has a “key” - values for each of a cluster of (% style="color:#e74c3c" %)concepts(%%), also called [[dimensions>>doc:Glossary.Dimension.WebHome]] - which identifies it, and one or more “observations”, which typically combine the time of the observation, and the value of the observation (e.g., measurement). Additionally, metadata may be attached at any (% style="color:#e74c3c" %)level(%%) of this structure as descriptive “[[attributes>>doc:Glossary.Attribute.WebHome]]”. [[Code lists>>doc:Glossary.Code list.WebHome]] (enumerations) and other patterns for [[representation>>doc:Glossary.Representation.WebHome]] of data and metadata are also modelled.
++[[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] recognizes that statistical data is structured; in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] this structure is termed a [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]]. “[[Data sets>>doc:Glossary.Data set.WebHome]]” are made up of one or more lower-level “groups”, based on their degrees of similarity. Each group is in turn comprised of one or more “series” of data. Each series or section has a “key” - values for each of a cluster of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%), also called [[dimensions>>doc:Glossary.Dimension.WebHome]] - which identifies it, and one or more “observations”, which typically combine the time of the observation, and the value of the observation (e.g., measurement). Additionally, metadata may be attached at any level of this structure as descriptive “[[attributes>>doc:Glossary.Attribute.WebHome]]”. [[Code lists>>doc:Glossary.Code list.WebHome]] (enumerations) and other patterns for [[representation>>doc:Glossary.Representation.WebHome]] of data and metadata are also modelled.
--There is some similarity between “cube” structures commonly used to process statistical data, and the [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] idea in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]]. It is important to note that the data as structured according to the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] is optimized for exchange, potentially with partners who may have no ability to process a “cube” of data coming from complex statistical systems. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] time series can be understood as “slices” of the cube. Such a slice is identified by its key. A "series" key consists of the values for all [[dimensions>>doc:Glossary.Dimension.WebHome]] specified by the key family except time. Thus, it is possible to reconstruct and describe data cubes from [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-structured data, and to exchange such databases using the interfaces and formats provided for that purpose in the standard. Additional objects such as [[hierarchical code lists>>doc:Glossary.Hierarchical code list.WebHome]], (% style="color:#e74c3c" %)constraints(%%) and structure (% style="color:#e74c3c" %)maps(%%) make it possible to more fully model the structure of cubes.
++There is some similarity between “cube” structures commonly used to process statistical data, and the [[Data Structure Definition>>doc:Glossary.Data structure definition.WebHome]] idea in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]]. It is important to note that the data as structured according to the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] is optimized for exchange, potentially with partners who may have no ability to process a “cube” of data coming from complex statistical systems. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] time series can be understood as “slices” of the cube. Such a slice is identified by its key. A "series" key consists of the values for all [[dimensions>>doc:Glossary.Dimension.WebHome]] specified by the key family except time. Thus, it is possible to reconstruct and describe data cubes from [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-structured data, and to exchange such databases using the interfaces and formats provided for that purpose in the standard. Additional objects such as [[hierarchical code lists>>doc:Glossary.Hierarchical code list.WebHome]], (% style="color:#e74c3c" %)constraints(%%) and structure maps make it possible to more fully model the structure of cubes.
--The information model also provides a view of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]]: a mechanism for referencing the meaningful “objects” within the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] view of statistical exchange processes ([[data providers>>doc:Glossary.Data provider.WebHome]], structures, [[provisioning agreements>>doc:Glossary.Provision agreement.WebHome]], [[dataflows>>doc:Glossary.Dataflow.WebHome]], [[metadata flows>>doc:Glossary.Metadataflow.WebHome]], etc.) to which metadata is attached; a mechanism for describing a set of meaningful (% style="color:#e74c3c" %)concepts(%%), of organizing them into a presentational structure, and of indicating how their values are represented. This is based on a simple, hierarchical view of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] which is common to many metadata systems and classification/categorization schemes. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provides a model (and XML and JSON formats) for both describing [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structures, and of reporting [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] according to those structures.
++The information model also provides a view of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]]: a mechanism for referencing the meaningful “objects” within the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] view of statistical exchange processes ([[data providers>>doc:Glossary.Data provider.WebHome]], structures, [[provisioning agreements>>doc:Glossary.Provision agreement.WebHome]], [[dataflows>>doc:Glossary.Dataflow.WebHome]], [[metadata flows>>doc:Glossary.Metadataflow.WebHome]], etc.) to which metadata is attached; a mechanism for describing a set of meaningful concepts, of organizing them into a presentational structure, and of indicating how their values are represented. This is based on a simple, hierarchical view of [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] which is common to many metadata systems and classification/categorization schemes. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] provides a model (and XML and JSON formats) for both describing [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] structures, and of reporting [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] according to those structures.
--(% style="color:#e74c3c" %)Version(%%) 2.0/2.1 introduced support for metadata related to the process aspects of statistical exchange. A step-by-step process can be modelled; information about who is providing data and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] and how they are providing it can be expressed; and the technical aspects of service-(% style="color:#e74c3c" %)level(%%) agreements (and similar types of [[provisioning agreements>>doc:Glossary.Provision agreement.WebHome]]) can be represented.
++Version 2.0/2.1 introduced support for metadata related to the process aspects of statistical exchange. A step-by-step process can be modelled; information about who is providing data and [[reference metadata>>doc:Glossary.Reference metadata.WebHome]] and how they are providing it can be expressed; and the technical aspects of service-level agreements (and similar types of [[provisioning agreements>>doc:Glossary.Provision agreement.WebHome]]) can be represented.
--Support for the [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]]) in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] was introduced in the July 2020 revision of 2.1 and is retained in (% style="color:#e74c3c" %)version(%%) 3.0 with minimal changes. This allows reusable [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] ‘programs’ (a cohesive set of transformation statements designed to be executed together) and their associated constructs such as validation rulesets and user-defined operators to be managed and exchanged as [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. Mappings between objects such as [[data sets>>doc:Glossary.Data set.WebHome]] referenced in [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] programs and the actual [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:Glossary.Artefact.WebHome]] to which they relate is essential when it comes to actually executing programs, and this information can also be defined. Chapter 7 has more information on [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] and its integration with [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]].
++Support for the [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]]) in the [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] was introduced in the July 2020 revision of 2.1 and is retained in version 3.0 with minimal changes. This allows reusable [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] ‘programs’ (a cohesive set of transformation statements designed to be executed together) and their associated constructs such as validation rulesets and user-defined operators to be managed and exchanged as [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. Mappings between objects such as [[data sets>>doc:Glossary.Data set.WebHome]] referenced in [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] programs and the actual [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:Glossary.Artefact.WebHome]] to which they relate is essential when it comes to actually executing programs, and this information can also be defined. Chapter 7 has more information on [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] and its integration with [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]].
  A full UML conceptual design of the information model is set out in Section 2 of the Technical Specifications.
@@ -298,7 +298,7 @@
  There are four distinct types of message:
--1. //Structure Definition~:// For the exchange of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. A [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] structure message can carry details of any number and combination of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] [[artefacts>>doc:Glossary.Artefact.WebHome]] like DSDs, [[code lists>>doc:Glossary.Code list.WebHome]] and (% style="color:#e74c3c" %)constraints(%%).
++1. //Structure Definition~:// For the exchange of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]]. A [[SDMX-ML>>doc:Glossary.SDMX-ML.WebHome]] structure message can carry details of any number and combination of [[structural metadata>>doc:Glossary.Structural metadata.WebHome]] [[artefacts>>doc:Glossary.Artefact.WebHome]] like [[DSD>>doc:sdmx:Glossary.Data structure definition.WebHome]]s, [[code lists>>doc:Glossary.Code list.WebHome]] and (% style="color:#e74c3c" %)[[constraints>>doc:sdmx:Glossary.Constraint.WebHome]](%%).
 . //Structure-specific Data~:// For the exchange of data. This format is specific to the [[Data Structure Definitions>>doc:Glossary.Data structure definition.WebHome]] of the [[data sets>>doc:Glossary.Data set.WebHome]] (in other terms, it is [[DSD>>doc:Glossary.Data structure definition.WebHome]]-specific) and is created by following mappings between the metadata constructs defined in the Structure Definition message and the technical specification of the format. It supports the exchange of large [[data sets>>doc:Glossary.Data set.WebHome]] in XML format, provides strict validation of conformance with the [[DSD>>doc:Glossary.Data structure definition.WebHome]] using a generic XML parser, and supports the transmission of partial [[data sets>>doc:Glossary.Data set.WebHome]] ([[incremental updates>>doc:Glossary.Incremental update.WebHome]]) as well as whole [[data sets>>doc:Glossary.Data set.WebHome]].
  Many XML tools and technologies have expectations about the functions performed by an XML schema, one of which is a very direct relationship between the XML constructs described in the XML schema and the tagged data in the XML instance. Strong data typing is also considered normal, supporting full validation of the tagged data. These message types are designed to support validation and other expected XML schema functions.
@@ -333,7 +333,7 @@
  == 5.4 Formats and Messages Deprecated in Version 3.0 ==
--The following formats and messages have been deprecated in (% style="color:#e74c3c" %)version(%%) 3.0 to simplify, modernise and rationalise the standard.
++The following formats and messages have been deprecated in version 3.0 to simplify, modernise and rationalise the standard.
  * SDMX-EDI
  * SDMX-ML 1.0/2.0 Generic (time-series) data message
@@ -343,7 +343,7 @@
  * SDMX-ML 2.1 Generic (Time Series) data messages (for observations, time-series and cross-sectional data)
  * SDMX-ML 2.1 Structure Specific Time Series data message
--The following messages were deprecated in (% style="color:#e74c3c" %)version(%%) 3.0 as a consequence of the deprecation of the SOAP web services:
++The following messages were deprecated in version 3.0 as a consequence of the deprecation of the SOAP web services:
  * SDMX-ML Query messages
  * SDMX-ML Submit Structure Request messages
@@ -350,37 +350,39 @@
  = 6 Dependencies on SDMX content-oriented guidelines =
--The technical standards proposed here are designed so that they can be used in conjunction with other [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] guidelines which are more closely tied to the content and semantics of statistical data exchange. The [[SDMX Information Model>>doc:Glossary.SDMX Information Model.WebHome]] works equally well with any statistical (% style="color:#e74c3c" %)concept(%%), but to encourage interoperability, it is also necessary to standardize and harmonize the use of specific (% style="color:#e74c3c" %)concepts(%%) and terminology. To achieve this goal, [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] creates and maintains guidelines for [[cross-domain concepts>>doc:Glossary.Cross-domain concept.WebHome]], terminology, and structural definitions. There are three major parts to this effort.
++The technical standards proposed here are designed so that they can be used in conjunction with other [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] guidelines which are more closely tied to the content and semantics of statistical data exchange. The [[SDMX Information Model>>doc:sdmx:Glossary.SDMX Information Model.WebHome]] works equally well with any statistical (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%), but to encourage interoperability, it is also necessary to standardize and harmonize the use of specific (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) and terminology. To achieve this goal, [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] creates and maintains guidelines for [[cross-domain concepts>>doc:sdmx:Glossary.Cross-domain concept.WebHome]], terminology, and structural definitions. There are three major parts to this effort.
  == 6.1 Cross-Domain Concepts ==
--The [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[Cross-Domain Concepts>>doc:Glossary.Cross-domain concept.WebHome]] is a content guideline concerning (% style="color:#e74c3c" %)concepts(%%) which are used across [[statistical domains>>doc:Glossary.Statistical subject-matter domain.WebHome]]. This list is expected to grow and to be subject to revision as [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] is used in a growing number of domains. The use of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[Cross-Domain Concepts>>doc:Glossary.Cross-domain concept.WebHome]], where appropriate, provides a framework to further promote interoperability among organisations using the technical standards presented here. The harmonization of statistical (% style="color:#e74c3c" %)concepts(%%) includes not only the definitions of the (% style="color:#e74c3c" %)concepts(%%), and their names, but also, where appropriate, their [[representation>>doc:Glossary.Representation.WebHome]] with standard [[code lists>>doc:Glossary.Code list.WebHome]], and the role they play within [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] and metadata structure definitions.
++The [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] [[Cross-Domain Concepts>>doc:sdmx:Glossary.Cross-domain concept.WebHome]] is a content guideline concerning (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) which are used across [[statistical domains>>doc:sdmx:Glossary.Statistical subject-matter domain.WebHome]]. This list is expected to grow and to be subject to revision as [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] is used in a growing number of domains. The use of the [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] [[Cross-Domain Concepts>>doc:sdmx:Glossary.Cross-domain concept.WebHome]], where appropriate, provides a framework to further promote interoperability among organisations using the technical standards presented here. The harmonization of statistical (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) includes not only the definitions of the (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%), and their names, but also, where appropriate, their [[representation>>doc:sdmx:Glossary.Representation.WebHome]] with standard [[code lists>>doc:sdmx:Glossary.Code list.WebHome]], and the role they play within [[data structure definitions>>doc:sdmx:Glossary.Data structure definition.WebHome]] and metadata structure definitions.
--The intent of this guideline is two-fold: to provide a core set of (% style="color:#e74c3c" %)concepts(%%) which can be used to structure statistical data and metadata, to promote interoperability between systems (“[[structural metadata>>doc:Glossary.Structural metadata.WebHome]]”, as described above); and to promote the exchange of metadata more widely, with a set of harmonized (% style="color:#e74c3c" %)concept(%%) names and definitions for other types of metadata (“[[reference metadata>>doc:Glossary.Reference metadata.WebHome]]”, as defined above.)
++The intent of this guideline is two-fold: to provide a core set of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) which can be used to structure statistical data and metadata, to promote interoperability between systems (“[[structural metadata>>doc:sdmx:Glossary.Structural metadata.WebHome]]”, as described above); and to promote the exchange of metadata more widely, with a set of harmonized (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) names and definitions for other types of metadata (“[[reference metadata>>doc:sdmx:Glossary.Reference metadata.WebHome]]”, as defined above.)
  == 6.2 Metadata Common Vocabulary ==
--The Metadata Common Vocabulary is an [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] guideline which provides definition of terms to be used for the comparison and mapping of terminology found in [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] and in other aspects of statistical metadata management. Essentially, it provides ISOcompliant definitions for a wide range of statistical terms, which may be used directly, or against which other terminology systems may be (% style="color:#e74c3c" %)mapped(%%). This set of terms is inclusive of the terminology used within the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Standards.
++The Metadata Common Vocabulary is an [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] guideline which provides definition of terms to be used for the comparison and mapping of terminology found in [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]] and in other aspects of statistical metadata management. Essentially, it provides ISOcompliant definitions for a wide range of statistical terms, which may be used directly, or against which other terminology systems may be mapped. This set of terms is inclusive of the terminology used within the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Standards.
--The MCV provides definitions for terms on which the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Cross-Domain Metadata (% style="color:#e74c3c" %)Concepts(%%) work is built.
++The MCV provides definitions for terms on which the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Cross-Domain Metadata (% style="color:#e74c3c" %)[[Concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) work is built.
  == 6.3 Statistical Subject-Matter Domains ==
--The [[Statistical Subject-Matter Domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] is a listing of the breadth of statistical information for the purposes of organizing widespread statistical exchange and categorization. It acts as a standard scheme against which the categorization schemes of various counterparties can be (% style="color:#e74c3c" %)mapped(%%), to facilitate interoperable data and metadata exchange. It serves another useful purpose, however, which is to allow an organization of corresponding “domain groups”, each of which could define standard [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]], (% style="color:#e74c3c" %)concepts(%%), etc. within their domains. Such groups already exist within the international community. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] would use the [[Statistical Subject-Matter Domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] list to facilitate the efforts of these groups to develop the kinds of content standards which could support the interoperation of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-conformant technical systems within and across [[statistical domains>>doc:Glossary.Statistical subject-matter domain.WebHome]]. The organisation of the content of such schemes is supported in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] as a [[Category>>doc:Glossary.Category.WebHome]] Scheme.
++The [[Statistical Subject-Matter Domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] is a listing of the breadth of statistical information for the purposes of organizing widespread statistical exchange and categorization. It acts as a standard scheme against which the categorization schemes of various counterparties can be mapped, to facilitate interoperable data and metadata exchange. It serves another useful purpose, however, which is to allow an organization of corresponding “domain groups”, each of which could define standard [[data structure definitions>>doc:Glossary.Data structure definition.WebHome]], (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%), etc. within their domains. Such groups already exist within the international community. [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] would use the [[Statistical Subject-Matter Domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] list to facilitate the efforts of these groups to develop the kinds of content standards which could support the interoperation of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]]-conformant technical systems within and across [[statistical domains>>doc:Glossary.Statistical subject-matter domain.WebHome]]. The organisation of the content of such schemes is supported in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] as a [[Category>>doc:Glossary.Category.WebHome]] Scheme.
  [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[Statistical Subject-Matter Domains>>doc:Glossary.Statistical subject-matter domain.WebHome]] will be listed and maintained by the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Initiative and will be subject to adjustment.
  == 6.4 SDMX Concept Roles ==
--These guidelines define the standard set of [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concept(%%) Roles and their use. This set of standard [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concepts(%%) are implemented as a [[cross-domain Concept>>doc:Glossary.Cross-domain concept.WebHome]] Scheme that defines the set of (% style="color:#e74c3c" %)concept(%%) roles and gives examples on (% style="color:#e74c3c" %)concept(%%) role implementation in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.0, 2.1 and 3.0. A (% style="color:#e74c3c" %)concept(%%) role gives a particular context to a (% style="color:#e74c3c" %)concept(%%) for easy and systematic interpretation by machine processing and visualization tools. For example, the (% style="color:#e74c3c" %)concepts(%%) REPORTING_AREA and COUNTERPART_AREA are different (% style="color:#e74c3c" %)concepts(%%) but they are both geographical characteristics, therefore they can be associated with the same (% style="color:#e74c3c" %)concept(%%) role ID: "GEO". This allows visualization systems to interpret these (% style="color:#e74c3c" %)concepts(%%) as geographical data in order to generate (% style="color:#e74c3c" %)maps(%%). The implementation of (% style="color:#e74c3c" %)concept(%%) roles is different in (% style="color:#e74c3c" %)versions(%%) 2.0 and 2.1/3.0 of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] technical standard. Specifically for [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 3.0, this set of roles is considered a normative list that must be interpreted in the same way by all organisations.
++These guidelines define the standard set of [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)[[Concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) Roles and their use. This set of standard [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)[[Concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) are implemented as a [[cross-domain Concept>>doc:sdmx:Glossary.Cross-domain concept.WebHome]] Scheme that defines the set of (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) roles and gives examples on (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) role implementation in [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] 2.0, 2.1 and 3.0. A (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) role gives a particular context to a (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) for easy and systematic interpretation by machine processing and visualization tools. For example, the (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) REPORTING_AREA and COUNTERPART_AREA are different (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) but they are both geographical characteristics, therefore they can be associated with the same (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) role ID: "GEO". This allows visualization systems to interpret these (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) as geographical data in order to generate maps. The implementation of (% style="color:#e74c3c" %)[[concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) roles is different in versions 2.0 and 2.1/3.0 of the [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] technical standard. Specifically for [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] 3.0, this set of roles is considered a normative list that must be interpreted in the same way by all organisations.
--Additional roles may be provided via the standard roles’ mechanism in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 3.0, i.e., via [[Concept Schemes>>doc:Glossary.Concept scheme.WebHome]]; the semantics of these roles have to be agreed bilateraly in data exchanges. The (% style="color:#e74c3c" %)Concept(%%) Roles are available as an [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] [[Concept Scheme>>doc:Glossary.Concept scheme.WebHome]] on the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Global Registry.
++Additional roles may be provided via the standard roles’ mechanism in [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] 3.0, i.e., via [[Concept Schemes>>doc:sdmx:Glossary.Concept scheme.WebHome]]; the semantics of these roles have to be agreed bilateraly in data exchanges. The (% style="color:#e74c3c" %)[[Concept>>doc:sdmx:Glossary.Concept.WebHome]](%%) Roles are available as an [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] [[Concept Scheme>>doc:sdmx:Glossary.Concept scheme.WebHome]] on the [[SDMX>>doc:sdmx:Glossary.Statistical data and metadata exchange.WebHome]] [[Global Registry>>doc:sdmx:Glossary.Global registry.WebHome]]
++.
++
  = 7 Validation and Transformation Language =
  For many years the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] initiative has been fostering and supporting the development of a standard calculation language, called [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]]). A blueprint for defining calculations was already described in the original [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 specifications (package 13 of the Information Model - “Transformations and Expressions”). It was just a basic framework that required further developments to became operational in order to achieve a calculation language able to manipulate [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] artefacts.
--These developments started in late 2012 and were put in charge of the [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] Task Force ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]] TF), which included members of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Working Group (TWG) and Statistical Working Group (SWG), besides experts coming from the DDI and GSIM communities. The intent was to define a standard language to be implemented in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] and applicable also to GSIM and DDI. This brought to the publication of the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.0 in 2015. Then new requirements came from a number of proofs of (% style="color:#e74c3c" %)concepts(%%) and tests of [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.0 made by several organisations and triggered a large improvement of the language. A new provisional (% style="color:#e74c3c" %)version(%%), the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.1, was released in public consultation in 2017. The high number of [[comments>>doc:Glossary.Comment.WebHome]] received triggered another phase of intensive work, with the main goal of achieving a more robust and forward compatible (% style="color:#e74c3c" %)version(%%). Finally, the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 2.0 was published between April and July 2018 (see the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] website).
++These developments started in late 2012 and were put in charge of the [[Validation and Transformation Language>>doc:Glossary.Validation and transformation language.WebHome]] Task Force ([[VTL>>doc:Glossary.Validation and transformation language.WebHome]] TF), which included members of the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] Technical Working Group (TWG) and Statistical Working Group (SWG), besides experts coming from the DDI and GSIM communities. The intent was to define a standard language to be implemented in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] and applicable also to GSIM and DDI. This brought to the publication of the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.0 in 2015. Then new requirements came from a number of proofs of (% style="color:#e74c3c" %)[[concepts>>doc:sdmx:Glossary.Concept.WebHome]](%%) and tests of [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.0 made by several organisations and triggered a large improvement of the language. A new provisional version, the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 1.1, was released in public consultation in 2017. The high number of [[comments>>doc:Glossary.Comment.WebHome]] received triggered another phase of intensive work, with the main goal of achieving a more robust and forward compatible version. Finally, the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 2.0 was published between April and July 2018 (see the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] website).
  The implementation of the [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 2.0 in [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] started in late 2018 and was published as an incremental revision to the [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] 2.1 standards in July 2020. It allows users to write [[VTL>>doc:Glossary.Validation and transformation language.WebHome]] 2.0 programs for validating and transforming [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] data, to store these programs in a [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] metadata registry and to exchange them through [[SDMX>>doc:Glossary.Statistical data and metadata exchange.WebHome]] messages, also together the definition of the data structures of the involved data.