Changes for page 4 General Notes for Implementers

Last modified by Helena K. on 2026/06/09 20:04

From 8.2 to 8.1 From 10.1 to 9.1

From version 9.1

edited by Helena K.
on 2026/06/09 20:04

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To version 8.2

edited by Helena K.
on 2026/06/09 19:55

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@@ -10,7 +10,7 @@
  There are several different [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]], taken from XML Schemas and common programming [[languages>>doc:sdmx:Glossary 2\.1.Language.WebHome]]. The table below describes the various [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]], which are found in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]], and their equivalents.
--|(% style="width:191px" %)**SDMX-ML Data Type**|(% style="width:232px" %)**XML Schema Data Type**|(% style="width:212px" %)**.NET Framework Type**|(% style="width:980px" %)(((
++|(% style="width:191px" %)**[[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] Data Type**|(% style="width:232px" %)**XML Schema Data Type**|(% style="width:212px" %)**.NET Framework Type**|(% style="width:980px" %)(((
  **Java Data Type**
  )))
  |(% style="width:191px" %)String|(% style="width:232px" %)xsd:string|(% style="width:212px" %)System.String|(% style="width:980px" %)java.lang.String
@@ -18,7 +18,7 @@
  |(% style="width:191px" %)Integer|(% style="width:232px" %)xsd:int|(% style="width:212px" %)System.Int32|(% style="width:980px" %)int
  |(% style="width:191px" %)Long|(% style="width:232px" %)xsd.long|(% style="width:212px" %)System.Int64|(% style="width:980px" %)long
  |(% style="width:191px" %)Short|(% style="width:232px" %)xsd:short|(% style="width:212px" %)System.Int16|(% style="width:980px" %)short
--|(% style="width:191px" %)[[Decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]|(% style="width:232px" %)xsd:decimal|(% style="width:212px" %)System.Decimal|(% style="width:980px" %)java.math.BigDecimal
++|(% style="width:191px" %)[[Decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]|(% style="width:232px" %)xsd:[[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]|(% style="width:212px" %)System.[[Decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]|(% style="width:980px" %)java.math.BigDecimal
  |(% style="width:191px" %)Float|(% style="width:232px" %)xsd:float|(% style="width:212px" %)System.Single|(% style="width:980px" %)float
  |(% style="width:191px" %)Double|(% style="width:232px" %)xsd:double|(% style="width:212px" %)System.Double|(% style="width:980px" %)double
  |(% style="width:191px" %)Boolean|(% style="width:232px" %)xsd:boolean|(% style="width:212px" %)System.Boolean|(% style="width:980px" %)boolean
@@ -37,9 +37,9 @@
  * **Alpha** (**common:AlphaType**, string which only allows A-z)
  * **Numeric** (**common:NumericType**, string which only allows 0-9, but is not numeric so that is can having leading zeros)
  * **Count** (**xs:integer**, a sequence with an interval of "1")
--* **InclusiveValueRange** (**xs:decimal** with the **minValue** and **maxValue** [[facets>>doc:sdmx:Glossary 2\.1.Facet.WebHome]] supplying the bounds)
--* **ExclusiveValueRange** (**xs:decimal** with the **minValue** and **maxValue** [[facets>>doc:sdmx:Glossary 2\.1.Facet.WebHome]] supplying the bounds)
--* **Incremental** (**xs:decimal** with a specified **interval**; the interval is typically enforced outside of the XML validation)
++* **InclusiveValueRange** (**xs:[[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** with the **minValue** and **maxValue** [[facets>>doc:sdmx:Glossary 2\.1.Facet.WebHome]] supplying the bounds)
++* **ExclusiveValueRange** (**xs:[[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** with the **minValue** and **maxValue** [[facets>>doc:sdmx:Glossary 2\.1.Facet.WebHome]] supplying the bounds)
++* **Incremental** (**xs:[[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** with a specified **interval**; the interval is typically enforced outside of the XML validation)
  * **TimeRange** (**common:TimeRangeType**, **startDateTime** + **Duration**)
  * **ObservationalTimePeriod** (**common:ObservationalTimePeriodType**, a union of **StandardTimePeriod** and **TimeRange**).
  * **StandardTimePeriod** (**common:StandardTimePeriodType**, a union of **BasicTimePeriod** and **ReportingTimePeriod**).
@@ -63,15 +63,14 @@
  * **isSequence = true | false** (indicates a sequentially increasing value)
  * **minLength = positive integer** (# of characters/digits)
  * **maxLength = positive integer** (# of characters/digits)
--* **startValue = decimal** (for numeric sequence)
--* **endValue = decimal** (for numeric sequence)
--* **interval = decimal** (for numeric sequence)
--* **timeInterval = duration**
++* **startValue = [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** (for numeric sequence)
++* **endValue = [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** (for numeric sequence)
++* **interval = [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** (for numeric sequence) • **timeInterval = duration**
  * **startTime = BasicTimePeriod** (for time range)
  * **endTime = BasicTimePeriod** (for time range)
--* **minValue = decimal** (for numeric range)
--* **maxValue = decimal** (for numeric range)
--* **decimal = Integer** (# of digits to right of [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]] point)
++* **minValue = [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** (for numeric range)
++* **maxValue = [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]]** (for numeric range)
++* **[[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]] = Integer** (# of digits to right of [[decimal>>doc:sdmx:Glossary 2\.1.Decimals.WebHome]] point)
  * **pattern =** (a regular expression, as per W3C XML Schema)
  * **isMultiLingual = boolean** (for specifying text can occur in more than one [[language>>doc:sdmx:Glossary 2\.1.Language.WebHome]])
@@ -79,7 +79,7 @@
  === 4.1.1 Data Types ===
--XML and JSON schemas support a variety of data types that, although rich, are not mapped one-to-one in all cases. This section provides an explanation of the mapping performed in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0, between such cases.
++XML and JSON schemas support a variety of data types that, although rich, are not (% style="color:#e74c3c" %)mapped(%%) one-to-one in all cases. This section provides an explanation of the mapping performed in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0, between such cases.
  For identifiers, text fields and [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] there are no restriction from either side, since a generic type (e.g., that of string) accompanied by the proper regular expression works equally well for both XML and JSON.
@@ -100,12 +100,12 @@
  >    "pattern": "^[A-Za-z0-9_@$-]+$"
  > }
--There are also cases, though, that data types cannot be mapped like above. One such case is the array data type, which was introduced in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 as a new [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. In JSON schema an array is already natively foreseen, while in the XML schema, this has to be defined as a complex type, with an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] specific definition (i.e., specific element/[[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] names for [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]). Beyond that, the minimum and/or maximum number of items within an array is possible in both cases.
++There are also cases, though, that data types cannot be (% style="color:#e74c3c" %)mapped(%%) like above. One such case is the array data type, which was introduced in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 as a new [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. In JSON schema an array is already natively foreseen, while in the XML schema, this has to be defined as a complex type, with an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] specific definition (i.e., specific element/[[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] names for [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]). Beyond that, the minimum and/or maximum number of items within an array is possible in both cases.
  Further to the above, the mapping between the non-native data types is presented in the table below:
  (% style="width:1005.83px" %)
--|(% style="width:198px" %)**SDMX Facet**|(% style="width:241px" %)**XML Schema**|(% style="width:563px" %)**JSON schema **"**pattern**"{{footnote}}Regular expressions, as specified in W3C XML Schema Definition Language (XSD) 1.1 Part 2: Datatypes.{{/footnote}} **for "string" type**
++|(% style="width:198px" %)**[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Facet>>doc:sdmx:Glossary 2\.1.Facet.WebHome]]**|(% style="width:241px" %)**XML Schema**|(% style="width:563px" %)**JSON schema **"**pattern**"{{footnote}}Regular expressions, as specified in W3C XML Schema Definition Language (XSD) 1.1 Part 2: Datatypes.{{/footnote}} **for "string" type**
  |(% style="width:198px" %)GregorianYear|(% style="width:241px" %)xsd:gYear|(% style="width:563px" %)(((
  "^-?([1-9][0-9]{3,}|0[0-9]{3})(Z|(\+|-)((0[0-9]|1[0-3]):[0-5][0-9]|14:00))?$"
  )))
@@ -230,7 +230,7 @@
  [[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]: common:ReportingDayType (YYYY-Dddd, e.g. 2000-D366) Notes: There are either 365 or 366 days in a reporting year, depending on whether the reporting year includes leap day (February 29). The reporting day is always represented as three digits, therefore 1-99 are 0 padded (e.g. 001). This allows the values to be sorted chronologically using textual sorting methods.
  The meaning of a reporting year is always based on the start day of the year and requires that the reporting year is expressed as the year at the start of the period. This start day is always the same for a reporting year, and is expressed as a day and a month (e.g. July 1). Therefore, the reporting year 2000 with a start day of July 1 begins on July 1, 2000.
--A specialized [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] (reporting year start day) exists for the purpose of communicating the reporting year start day. This [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] has a fixed identifier (REPORTING_YEAR_START_DAY) and a fixed [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (xs:gMonthDay) so that it can always be easily identified and processed in a data message. Although this [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] exists in specialized sub-class, it functions the same as any other [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] outside of its identification and [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. It must takes its identity from a [[concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] and state its relationship with other [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] of the [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]. The ability to state this relationship allows this reporting year start day [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] to exist at the appropriate levels of a data message. In the absence of this [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]], the reporting year start date is assumed to be January 1; therefore if the reporting year coincides with the calendar year, this [[Attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] is not necessary.
++A specialized [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] (reporting year start day) exists for the purpose of communicating the reporting year start day. This [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] has a fixed identifier (REPORTING_YEAR_START_DAY) and a fixed [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (xs:gMonthDay) so that it can always be easily identified and processed in a data message. Although this [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] exists in specialized sub-class, it functions the same as any other [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] outside of its identification and [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. It must takes its identity from a (% style="color:#e74c3c" %)concept(%%) and state its relationship with other [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] of the [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]]. The ability to state this relationship allows this reporting year start day [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] to exist at the appropriate (% style="color:#e74c3c" %)levels(%%) of a data message. In the absence of this [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]], the reporting year start date is assumed to be January 1; therefore if the reporting year coincides with the calendar year, this [[Attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] is not necessary.
  Since the duration and the reporting year start day are known for any reporting period, it is possible to relate any reporting period to a distinct calendar period. The actual Gregorian calendar period covered by the reporting period can be computed as follows (based on the standard format of [REPROTING_YEAR]-[PERIOD_INDICATOR][PERIOD_VALUE] and the reporting year start day as [REPORTING_YEAR_START_DAY]):
@@ -241,7 +241,7 @@
  a) **If the [PERIOD_INDICATOR] is W:**
  **~1. If [REPORTING_YEAR_START_DATE] is a Friday, Saturday, or Sunday:**
--Add[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^~[4~]^^>>path:#_ftn4]](%%) (P3D, P2D, or P1D respectively) to the
++Add[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^~[4~]^^>>path:#_ftn4]](%%) (P3D, P2D, or P1D respectively) to the
  [REPORTING_YEAR_START_DATE]. The result is the [REPORTING_YEAR_BASE].
 . **If [REPORTING_YEAR_START_DATE] is a Monday, Tuesday, Wednesday, or Thursday:**
@@ -328,10 +328,10 @@
  === 4.2.8 Time Format ===
--In version 2.0 of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] there is a recommendation to use the [[time format>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] to gives additional information on the way time is represented in the message. Following an appraisal of its usefulness this is no longer required. However, it is still possible, if required , to include the [[time format>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]].
++In (% style="color:#e74c3c" %)version(%%) 2.0 of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] there is a recommendation to use the [[time format>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] to gives additional information on the way time is represented in the message. Following an appraisal of its usefulness this is no longer required. However, it is still possible, if required , to include the [[time format>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] in [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]].
  (% style="width:890.835px" %)
--|(% style="width:95px" %)**Code**|(% style="width:793px" %)**Format**
++|(% style="width:95px" %)**[[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]]**|(% style="width:793px" %)**Format**
  |(% style="width:95px" %)OTP|(% style="width:793px" %)Observational [[Time Period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]]: Superset of all [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[time formats>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] (Gregorian [[Time Period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]], Reporting [[Time Period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]], and Time Range)
  |(% style="width:95px" %)STP|(% style="width:793px" %)Standard [[Time Period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]]: Superset of Gregorian and Reporting [[Time Periods>>doc:sdmx:Glossary 2\.1.Time period.WebHome]]
  |(% style="width:95px" %)GTP|(% style="width:793px" %)Superset of all Gregorian [[Time Periods>>doc:sdmx:Glossary 2\.1.Time period.WebHome]] and date-time
@@ -352,7 +352,7 @@
  |(% style="width:95px" %)RD|(% style="width:793px" %)Reporting Day (YYYY-Dddd)
  (% class="wikigeneratedid" id="HTable1:SDMX-MLTimeFormatCodes" %)
--**Table 1: SDMX-ML Time Format Codes**
++**Table 1: [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] [[Time Format>>doc:sdmx:Glossary 2\.1.Time format.WebHome]] [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]]**
  === 4.2.9 Time Zones ===
@@ -373,7 +373,7 @@
  * Reporting Day: 2006-D156**-05:00**
  * Reporting Year Start Day: 07-01**-05:00**
--According to ISO 8601, a date without a time-zone is considered "local time". [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] assumes that local time is that of the sender of the message. In this version of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], an optional field is added to the sender definition in the header for specifying a time zone. This field has a default value of 'Z' (UTC). This determination of local time applies for all dates in a message.
++According to ISO 8601, a date without a time-zone is considered "local time". [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] assumes that local time is that of the sender of the message. In this (% style="color:#e74c3c" %)version(%%) of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], an optional field is added to the sender definition in the header for specifying a time zone. This field has a default value of 'Z' (UTC). This determination of local time applies for all dates in a message.
  === 4.2.10 Representing Time Spans Elsewhere ===
@@ -391,7 +391,7 @@
  === 4.2.12 Effect on Time Ranges ===
--All [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] data messages are capable of functioning in a manner similar to SDMXEDI if the [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] at the observation level is time: the [[time period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]] for the first observation can be stated and the rest of the observations can omit the time value as it can be derived from the start time and the frequency. Since the frequency can be determined based on the actual format of the time value for everything but distinct points in time and time ranges, this makes is even simpler to process as the interval between time ranges is known directly from the time value.
++All [[SDMX-ML>>doc:sdmx:Glossary 2\.1.SDMX-ML.WebHome]] data messages are capable of functioning in a manner similar to SDMXEDI if the [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] at the observation (% style="color:#e74c3c" %)level(%%) is time: the [[time period>>doc:sdmx:Glossary 2\.1.Time period.WebHome]] for the first observation can be stated and the rest of the observations can omit the time value as it can be derived from the start time and the frequency. Since the frequency can be determined based on the actual format of the time value for everything but distinct points in time and time ranges, this makes is even simpler to process as the interval between time ranges is known directly from the time value.
  === 4.2.13 Time in Query Messages ===
@@ -441,50 +441,50 @@
  * 2010-T3 (any reporting year start day)
  * 2010-Q3 or later (any reporting year start day)
  * 2010-M07 or later (any reporting year start day)
--* 2010-W27 or later (reporting year start day ~-~-01-01){{footnote}}2010-Q3 (with a reporting year start day of 01-01) starts on 2010-07-01. This is day 4 of week 26, therefore the first week matched is week 27.{{/footnote}}
++* 2010-W27 or later (reporting year start day ~-~-01-01){{footnote}}2010-Q3 (with a reporting year start day of --01-01) starts on 2010-07-01. This is day 4 of week 26, therefore the first week matched is week 27.{{/footnote}}
  * 2010-D182 or later (reporting year start day ~-~-01-01)
--* 2010-W28 or later (reporting year start day ~-~-07-01){{footnote}}2010-Q3 (with a reporting year start day of 07-01) starts on 2011-01-01. This is day 6 of week 27, therefore the first week matched is week 28.{{/footnote}}
++* 2010-W28 or later (reporting year start day ~-~-07-01){{footnote}}2010-Q3 (with a reporting year start day of --07-01) starts on 2011-01-01. This is day 6 of week 27, therefore the first week matched is week 28.{{/footnote}}
  * 2010-D185 or later (reporting year start day ~-~-07-01)
  == 4.3 Versioning ==
--Versioning operates at the level of versionable and maintainable objects in the [[SDMX information model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]. Within the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure and MetadataSet messages, there is a well-defined pattern for [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] versioning and referencing. The [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] identifiers are qualified by their [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] numbers – that is, an object with an Agency of "A", and ID of "X" and a [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of "1.0.0" is a different object than one with an Agency of "A", an ID of "X", and a [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of "1.1.0".
++Versioning operates at the (% style="color:#e74c3c" %)level(%%) of versionable and maintainable objects in the [[SDMX information model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]. Within the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure and MetadataSet messages, there is a well-defined pattern for [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] versioning and referencing. The [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] identifiers are qualified by their (% style="color:#e74c3c" %)version(%%) numbers – that is, an object with an Agency of "A", and ID of "X" and a (% style="color:#e74c3c" %)version(%%) of "1.0.0" is a different object than one with an Agency of "A", an ID of "X", and a (% style="color:#e74c3c" %)version(%%) of "1.1.0".
--As of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0, the versioning rules are extended to allow for truly versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] through the implementation of the rules of the well-known practice called "Semantic Versioning" ([[http:~~/~~/semver.org>>https://http:semver.org]]), in addition to the legacy non-restrictive versioning scheme. In addition, the "isFinal" property is removed from //MaintainableArtefact//. According to the legacy versioning, any [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] defined without a [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] is equivalent to following the legacy versioning, thus having [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] ‘1.0’.
++As of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0, the versioning rules are extended to allow for truly versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] through the implementation of the rules of the well-known practice called "Semantic Versioning" ([[http:~~/~~/semver.org>>https://http:semver.org]]), in addition to the legacy non-restrictive versioning scheme. In addition, the "isFinal" property is removed from //MaintainableArtefact//. According to the legacy versioning, any [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] defined without a (% style="color:#e74c3c" %)version(%%) is equivalent to following the legacy versioning, thus having (% style="color:#e74c3c" %)version(%%) ‘1.0’.
  === 4.3.1 Non-versioned artefacts ===
--Indeed, some use cases do not need or are incompatible with versioning for some or all their structural [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], such as the Agency, [[Data Providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]], Metadata Providers and [[Data Consumer Schemes>>doc:sdmx:Glossary 2\.1.Data consumer scheme.WebHome]]. These [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] follow the legacy versioning, with a fixed [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] set to ‘1.0’.
++Indeed, some use cases do not need or are incompatible with versioning for some or all their structural [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], such as the Agency, [[Data Providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]], Metadata Providers and [[Data Consumer Schemes>>doc:sdmx:Glossary 2\.1.Data consumer scheme.WebHome]]. These [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] follow the legacy versioning, with a fixed (% style="color:#e74c3c" %)version(%%) set to ‘1.0’.
--Many existing organisation’s data management systems work with [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]]-less structures and apply ad-hoc [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]] governance processes. The new nonversioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] will allow supporting those numerous situations, where organisations do not manage [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] numbers.
++Many existing organisation’s data management systems work with (% style="color:#e74c3c" %)version(%%)-less structures and apply ad-hoc [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]] governance processes. The new nonversioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] will allow supporting those numerous situations, where organisations do not manage (% style="color:#e74c3c" %)version(%%) numbers.
  === 4.3.2 Semantically versioned artefacts ===
--Since the purpose of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] versioning is to allow communicating the structural [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] changes to [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] partners and connected systems, [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 offers Semantic Versioning (aka SemVer) with a clear and unambiguous syntax to all semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 structural [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. Semantic versioning will thus better respond to situations where the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standard itself is the only structural contract between [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] and [[data consumers>>doc:sdmx:Glossary 2\.1.Data consumer.WebHome]] and where changes in structures can only be communicated through the [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] number increases.
++Since the purpose of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] versioning is to allow communicating the structural [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] changes to [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]] partners and connected systems, [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 offers Semantic Versioning (aka SemVer) with a clear and unambiguous syntax to all semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 structural [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. Semantic versioning will thus better respond to situations where the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] standard itself is the only structural contract between [[data providers>>doc:sdmx:Glossary 2\.1.Data provider.WebHome]] and [[data consumers>>doc:sdmx:Glossary 2\.1.Data consumer.WebHome]] and where changes in structures can only be communicated through the (% style="color:#e74c3c" %)version(%%) number increases.
--The semantic [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] number consists of four parts: MAJOR, MINOR, PATCH and EXTENSION, the first three parts being separated by a dot (.), the last two parts being separated by a hyphen : MAJOR.MINOR.PATCH-EXTENSION. All [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]] are ordered.
++The semantic (% style="color:#e74c3c" %)version(%%) number consists of four parts: MAJOR, MINOR, PATCH and EXTENSION, the first three parts being separated by a dot (.), the last two parts being separated by a hyphen : MAJOR.MINOR.PATCH-EXTENSION. All (% style="color:#e74c3c" %)versions(%%) are ordered.
  The detailed rules for semantic versioning are listed in chapter 14 in the annex for “Semantic Versioning”. In short, they define:
--Given a [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] number MAJOR.MINOR.PATCH (without EXTENSION), when making changes to that semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], then one must increment the:
++Given a (% style="color:#e74c3c" %)version(%%) number MAJOR.MINOR.PATCH (without EXTENSION), when making changes to that semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], then one must increment the:
--1. MAJOR [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] when backwards incompatible [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] changes are made,
--1. MINOR [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] when [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] elements are added in a backwards compatible manner, or
--1. PATCH [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] when backwards compatible [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] property changes are made.
++1. MAJOR (% style="color:#e74c3c" %)version(%%) when backwards incompatible [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] changes are made,
++1. MINOR (% style="color:#e74c3c" %)version(%%) when [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] elements are added in a backwards compatible manner, or
++1. PATCH (% style="color:#e74c3c" %)version(%%) when backwards compatible [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] property changes are made.
--When incrementing a [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] part, the right-hand side parts are 0-ed (reset to ‘0’).
++When incrementing a (% style="color:#e74c3c" %)version(%%) part, the right-hand side parts are 0-ed (reset to ‘0’).
  Extensions can be added, changed or dropped.
--Given an extended [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] number MAJOR.MINOR.PATCH-EXTENSION, when making changes to that versioned [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], then one is not required to increment the [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] if those changes are within the allowed scope of the [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] increment from the previous [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] (if that existed); otherwise, the above [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] increment rules apply. EXTENSIONs can be used e.g., for drafting or a pre-release.
++Given an extended (% style="color:#e74c3c" %)version(%%) number MAJOR.MINOR.PATCH-EXTENSION, when making changes to that versioned [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], then one is not required to increment the (% style="color:#e74c3c" %)version(%%) if those changes are within the allowed scope of the (% style="color:#e74c3c" %)version(%%) increment from the previous (% style="color:#e74c3c" %)version(%%) (if that existed); otherwise, the above (% style="color:#e74c3c" %)version(%%) increment rules apply. EXTENSIONs can be used e.g., for drafting or a pre-release.
--Semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] will thus be safe to use. Specific [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] patterns allow them to become either immutable, i.e., the maintainer commits to never change their content, or changeable only within a well-defined scope. If any further change is required, a new [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] must be created first. Furthermore, the impact of the further change is communicated using a clear [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] increment. The built-in [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] extension facility allows for eased drafting of new [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]].
++Semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] will thus be safe to use. Specific (% style="color:#e74c3c" %)version(%%) patterns allow them to become either immutable, i.e., the maintainer commits to never change their content, or changeable only within a well-defined scope. If any further change is required, a new (% style="color:#e74c3c" %)version(%%) must be created first. Furthermore, the impact of the further change is communicated using a clear (% style="color:#e74c3c" %)version(%%) increment. The built-in (% style="color:#e74c3c" %)version(%%) extension facility allows for eased drafting of new [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] (% style="color:#e74c3c" %)versions(%%).
--The production [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of [[identifiable artefacts>>doc:sdmx:Glossary 2\.1.Identifiable artefact.WebHome]] are assumed stable, i.e., they do not have an EXTENSION. This is because once in production, an [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] cannot change in any way, or it must change the [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]]. For cases where an [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] is not static, like during the drafting, the [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] must indicate this by including an EXTENSION. Draft [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] should not be used outside of a specific system designed to accommodate them. For most purposes, all [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] should become stable before being used in production.
++The production (% style="color:#e74c3c" %)versions(%%) of [[identifiable artefacts>>doc:sdmx:Glossary 2\.1.Identifiable artefact.WebHome]] are assumed stable, i.e., they do not have an EXTENSION. This is because once in production, an [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] cannot change in any way, or it must change the (% style="color:#e74c3c" %)version(%%). For cases where an [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] is not static, like during the drafting, the (% style="color:#e74c3c" %)version(%%) must indicate this by including an EXTENSION. Draft [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] should not be used outside of a specific system designed to accommodate them. For most purposes, all [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] should become stable before being used in production.
  === 4.3.3 Legacy-versioned artefacts ===
--Organisations wishing to keep a maximum of backwards compatibility with existing implementations can continue using the previous 2-digit convention for [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] numbers (MAJOR.MINOR) as in the past, such as '2.3', but without the ‘isFinal’ property. The new [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 standard does not add any strict rules or guarantees about changes in those [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], since the legacy versioning rules were rather loose and non-binding, including the meaning of the ‘isFinal’ property, and their implementations were varying.
++Organisations wishing to keep a maximum of backwards compatibility with existing implementations can continue using the previous 2-digit convention for (% style="color:#e74c3c" %)version(%%) numbers (MAJOR.MINOR) as in the past, such as '2.3', but without the ‘isFinal’ property. The new [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 standard does not add any strict rules or guarantees about changes in those [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], since the legacy versioning rules were rather loose and non-binding, including the meaning of the ‘isFinal’ property, and their implementations were varying.
  In order to make [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] immutable or changes truly predictable, a move to the new semantic versioning syntax is required.
@@ -492,28 +492,28 @@
  New flexible dependency specifications with wildcarding allow for easier data model maintenance and enhancements for semantically versioned [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. This allows implementing a smart referencing mechanism, whereby an [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] may reference:
--* a fixed [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]
--* the **latest available** [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]
--* the **latest backward compatible** [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], or the **latest backward and forward** **compatible** [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]].
++* a fixed (% style="color:#e74c3c" %)version(%%) of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]
++* the **latest available** (% style="color:#e74c3c" %)version(%%) of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]
++* the **latest backward compatible** (% style="color:#e74c3c" %)version(%%) of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], or the **latest backward and forward** **compatible** (% style="color:#e74c3c" %)version(%%) of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]].
--References not representing a strict [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] dependency, such as the target [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] defined in a MetadataProvisionAgreement allow for linking to **all currently available** [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]] of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. Another illustrative case for such loose referencing is that of [[Constraints>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] and flows. A [[Constraint>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] may reference many [[Dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] or [[Metadataflows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]], the addition of more references to flow objects does not [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] the [[Constraint>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]]. This is because the [[Constraints>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] are not properties of the flows – they merely make references to them.
++References not representing a strict [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] dependency, such as the target [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] defined in a MetadataProvisionAgreement allow for linking to **all currently available** (% style="color:#e74c3c" %)versions(%%) of another [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. Another illustrative case for such loose referencing is that of (% style="color:#e74c3c" %)Constraints(%%) and flows. A (% style="color:#e74c3c" %)Constraint(%%) may reference many [[Dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] or [[Metadataflows>>doc:sdmx:Glossary 2\.1.Metadataflow.WebHome]], the addition of more references to flow objects does not (% style="color:#e74c3c" %)version(%%) the (% style="color:#e74c3c" %)Constraint(%%). This is because the (% style="color:#e74c3c" %)Constraints(%%) are not properties of the flows – they merely make references to them.
--Semantically versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] must only reference other semantically versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], which may include extended [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]]. Non-versioned and legacy-versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] can reference any other non-versioned or versioned (whether semantic or legacy) [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. The scope of wildcards in references adapts correspondingly.
++Semantically versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] must only reference other semantically versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], which may include extended (% style="color:#e74c3c" %)versions(%%). Non-versioned and legacy-versioned [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] can reference any other non-versioned or versioned (whether semantic or legacy) [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]]. The scope of wildcards in references adapts correspondingly.
  The mechanism named "early binding" refers to a dependency on a stable versioned [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] – everything with a stable versioned identity is a known quantity and will not change. The "late binding" mechanism is based on a wildcarded reference, and it resolves that reference and determines the currently related [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] at runtime.
--One area which is much impacted by this versioning scheme is the ability to reference external objects. With the many dependencies within the various structural objects in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], it is useful to have a scheme for external referencing. This is done at the level of maintainable objects (DSDs, [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], [[Concept Schemes>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]], etc.) In an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure Message, whenever an "[[isExternalReference>>doc:sdmx:Glossary 2\.1.isExternalReference.WebHome]]" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] is set to true, then the application must resolve the address provided in the associated "uri" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] and use the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure Message stored at that location for the full definition of the object in question. Alternately, if a registry "urn" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] has been provided, the registry can be used to supply the full details of the object.
++One area which is much impacted by this versioning scheme is the ability to reference external objects. With the many dependencies within the various structural objects in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], it is useful to have a scheme for external referencing. This is done at the (% style="color:#e74c3c" %)level(%%) of maintainable objects (DSDs, [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], [[Concept Schemes>>doc:sdmx:Glossary 2\.1.Concept scheme.WebHome]], etc.) In an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure Message, whenever an "[[isExternalReference>>doc:sdmx:Glossary 2\.1.isExternalReference.WebHome]]" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] is set to true, then the application must resolve the address provided in the associated "uri" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] and use the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] Structure Message stored at that location for the full definition of the object in question. Alternately, if a registry "urn" [[attribute>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]] has been provided, the registry can be used to supply the full details of the object.
  The detailed rules for dependency management and references are listed in chapter 14 in the annex for “Semantic Versioning”.
--In order to allow resolving the described new forms of dependencies, the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 Rest API supports retrievals legacy-versioned, wildcarded and extended [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]]:
++In order to allow resolving the described new forms of dependencies, the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] 3.0 Rest API supports retrievals legacy-versioned, wildcarded and extended [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] (% style="color:#e74c3c" %)versions(%%):
--* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for a **specific** [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] (X.Y, X.Y.Z or X.Y.Z-EXT).
--* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for **latest available** semantic [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]] within the wildcard scope (X+.Y.Z, X.Y+.Z or X.Y.Z+).
++* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for a **specific** (% style="color:#e74c3c" %)version(%%) (X.Y, X.Y.Z or X.Y.Z-EXT).
++* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for **latest available** semantic (% style="color:#e74c3c" %)versions(%%) within the wildcard scope (X+.Y.Z, X.Y+.Z or X.Y.Z+).
  * Queries for **non-versioned** [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]].
--* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for **all available** semantic [[versions>>doc:sdmx:Glossary 2\.1.Version.WebHome]] within the wildcard scope (*, X.* or X.Y.*), where only the first form is required for resolving wildcarded loose references.
++* [[Artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] queries for **all available** semantic (% style="color:#e74c3c" %)versions(%%) within the wildcard scope (*, X.* or X.Y.*), where only the first form is required for resolving wildcarded loose references.
--The combination of wildcarded queries with a specific [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]] extension is not permitted.
++The combination of wildcarded queries with a specific (% style="color:#e74c3c" %)version(%%) extension is not permitted.
  Full details can be found in the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] RESTful web services specification.