Changes for page 12 Validation and Transformation Language (VTL)

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	1	+Artefact\|Attribute\|Code\|Code list\|Component\|Concept scheme\|Currency\|Data set\|Data structure definition\|Dataflow\|Dimension\|Facet\|Maintainable artefact\|Measure\|Nameable artefact\|Representation\|SDMX Information Model\|Statistical data and metadata exchange\|Structural metadata\|Validation and transformation language

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@@ -336,18 +336,18 @@
  If desired, this method can be applied also to mono-[[measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] structures, provided that none of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] has already the role of [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] Identifier. Like in the general case, a MeasureDimension [[component>>doc:sdmx:Glossary 2\.1.Component.WebHome]] called “measure_name” is added to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DataStructure, in this case it has just one possible [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]], corresponding to the name of the unique [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]]. The original [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] would not become a [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]] in the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data structure. The value of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] would be assigned to the unique [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] called “obs_value”.
--In any case, the resulting [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] definitions must be compliant with the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] consistency rules. For example, the possible [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] MeasureDimension need to be listed in a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], with proper id, agency and [[version>>doc:sdmx:Glossary 2\.1.Version.WebHome]]; moreover, the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] must have the AttributeRelationship for the DataAttributes, which does not exist in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]].
++In any case, the resulting [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] definitions must be compliant with the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] consistency rules. For example, the possible [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] MeasureDimension need to be listed in a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]], with proper id, agency and (% style="color:#e74c3c" %)version(%%); moreover, the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[DSD>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]] must have the AttributeRelationship for the DataAttributes, which does not exist in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]].
  ==== 12.3.4.3 From VTL Measures to SDMX Data Attributes ====
--More than all for the multi-[[measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] structures (having more than one [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]]), it may happen that the [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Data Structure need to be managed as DataAttributes in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]. Therefore, a third mapping method consists in transforming some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] in a corresponding [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] and all the other [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DataAttributes. This method is called M2A (“M2A” stands for “[[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] to DataAttributes”).
++More than all for the multi-[[measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] structures (having more than one [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]]), it may happen that the [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Data Structure need to be managed as DataAttributes in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]. Therefore, a third (% style="color:#e74c3c" %)mapping(%%) method consists in transforming some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] in a corresponding [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] and all the other [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DataAttributes. This method is called M2A (“M2A” stands for “[[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] to DataAttributes”).
  All [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] maintain their names in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]. The [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] that become [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DataAttributes are the ones declared as DataAttributes in the target [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[data structure definition>>doc:sdmx:Glossary 2\.1.Data structure definition.WebHome]].
--The mapping table is the following:
++The (% style="color:#e74c3c" %)mapping(%%) table is the following:
  (% style="width:467.294px" %)
--|(% style="width:214px" %)VTL|(% style="width:250px" %)SDMX
++|(% style="width:214px" %)[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]|(% style="width:250px" %)[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]
  |(% style="width:214px" %)(Simple) Identifier|(% style="width:250px" %)[[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]
  |(% style="width:214px" %)(Time) Identifier|(% style="width:250px" %)TimeDimension
  |(% style="width:214px" %)Some [[Measures>>doc:sdmx:Glossary 2\.1.Measure.WebHome]]|(% style="width:250px" %)[[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]]
@@ -358,33 +358,33 @@
  === 12.3.5 Declaration of the mapping methods between data structures ===
--In order to define and understand properly [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, the applied mapping methods must be specified in the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]. If the default mapping method (Basic) is applied, no specification is needed.
++In order to define and understand properly [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, the applied (% style="color:#e74c3c" %)mapping(%%) methods must be specified in the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[structural metadata>>doc:sdmx:Glossary 2\.1.Structural metadata.WebHome]]. If the default (% style="color:#e74c3c" %)mapping(%%) method (Basic) is applied, no specification is needed.
--A customized mapping can be defined through the VtlMappingScheme and VtlDataflowMapping classes (see the section of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] IM relevant to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]). A VtlDataflowMapping allows specifying the mapping methods to be used for a specific [[dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], both in the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] (toVtlMappingMethod) and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (fromVtlMappingMethod); in fact a VtlDataflowMapping associates the structured URN that identifies a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to its [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] alias and its mapping methods.
++A customized (% style="color:#e74c3c" %)mapping(%%) can be defined through the VtlMappingScheme and VtlDataflowMapping classes (see the section of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] IM relevant to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]). A VtlDataflowMapping allows specifying the (% style="color:#e74c3c" %)mapping(%%) methods to be used for a specific [[dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], both in the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] (toVtlMappingMethod) and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (fromVtlMappingMethod); in fact a VtlDataflowMapping associates the structured URN that identifies a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to its [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] alias and its (% style="color:#e74c3c" %)mapping(%%) methods.
--It is possible to specify the toVtlMappingMethod and fromVtlMappingMethod also for the conventional [[dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] called "generic_dataflow": in this case the specified mapping methods are intended to become the default ones, overriding the "Basic" methods. In turn, the toVtlMappingMethod and fromVtlMappingMethod declared for a specific [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are intended to override the default ones for such a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]].
++It is possible to specify the toVtlMappingMethod and fromVtlMappingMethod also for the conventional [[dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] called "generic_dataflow": in this case the specified (% style="color:#e74c3c" %)mapping(%%) methods are intended to become the default ones, overriding the "Basic" methods. In turn, the toVtlMappingMethod and fromVtlMappingMethod declared for a specific [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are intended to override the default ones for such a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]].
  The VtlMappingScheme is a container for zero or more VtlDataflowMapping (it may contain also mappings towards [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] other than [[dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]).
  === 12.3.6 Mapping dataflow subsets to distinct VTL Data Sets ===
--Until now it has been assumed to map one SMDX [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to one [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and vice-versa. This mapping one-to-one is not mandatory according to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] because a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is meant to be a set of observations (data points) on a logical plane, having the same logical data structure and the same general meaning, independently of the possible physical [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] or storage (see [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] 2.0 User Manual page 24), therefore a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] can be seen either as a unique set of data observations (corresponding to one [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]) or as the union of many sets of data observations (each one corresponding to a distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]).
++Until now it has been assumed to (% style="color:#e74c3c" %)map(%%) one SMDX [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to one [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] and vice-versa. This (% style="color:#e74c3c" %)mapping(%%) one-to-one is not mandatory according to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] because a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is meant to be a set of observations (data points) on a logical plane, having the same logical data structure and the same general meaning, independently of the possible physical [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] or storage (see [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] 2.0 User Manual page 24), therefore a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] can be seen either as a unique set of data observations (corresponding to one [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]) or as the union of many sets of data observations (each one corresponding to a distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]).
  As a matter of fact, in some cases it can be useful to define [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operations involving definite parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] instead than the whole.{{footnote}}A typical example of this kind is the validation, and more in general the manipulation, of individual time series belonging to the same Dataflow, identifiable through the DimensionComponents of the Dataflow except the TimeDimension. The coding of these kind of operations might be simplified by mapping distinct time series (i.e. different parts of a SDMX Dataflow) to distinct VTL Data Sets.{{/footnote}}
--Therefore, in order to make the coding of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operations simpler when applied on parts of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], it is allowed to map distinct parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] according to the following rules and conventions. This kind of mapping is possible both from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], as better explained below.{{footnote}}Please note that this kind of mapping is only an option at disposal of the definer of VTL Transformations; in fact it remains always possible to manipulate the needed parts of SDMX Dataflows by means of VTL operators (e.g. “sub”, “filter”, “calc”, “union” …), maintaining a mapping one-to-one between SDMX Dataflows and VTL Data Sets.{{/footnote}}
++Therefore, in order to make the coding of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operations simpler when applied on parts of [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], it is allowed to (% style="color:#e74c3c" %)map(%%) distinct parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] according to the following rules and conventions. This kind of (% style="color:#e74c3c" %)mapping(%%) is possible both from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], as better explained below.{{footnote}}Please note that this kind of mapping is only an option at disposal of the definer of VTL Transformations; in fact it remains always possible to manipulate the needed parts of SDMX Dataflows by means of VTL operators (e.g. “sub”, “filter”, “calc”, “union” …), maintaining a mapping one-to-one between SDMX Dataflows and VTL Data Sets.{{/footnote}}
--Given a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] and some predefined [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of its DataStructure, it is allowed to map the subsets of observations that have the same combination of values for such [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] to correspondent [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
++Given a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] and some predefined [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] of its DataStructure, it is allowed to (% style="color:#e74c3c" %)map(%%) the subsets of observations that have the same combination of values for such [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] to correspondent [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].
--For example, assuming that the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF1(1.0.0) has the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]], TIME_PERIOD and COUNTRY, and that the user declares the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY as basis for the mapping (i.e. the mapping [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]): the observations that have the same values for [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY would be mapped to the same [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (and vice-versa). In practice, this kind mapping is obtained like follows:
++For example, assuming that the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF1(1.0.0) has the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]], TIME_PERIOD and COUNTRY, and that the user declares the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY as basis for the (% style="color:#e74c3c" %)mapping(%%) (i.e. the (% style="color:#e74c3c" %)mapping(%%) [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]): the observations that have the same values for [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY would be (% style="color:#e74c3c" %)mapped(%%) to the same [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (and vice-versa). In practice, this kind (% style="color:#e74c3c" %)mapping(%%) is obtained like follows:
--* For a given [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], the user ([[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] definer) declares the DimensionComponents on which the mapping will be based, in a given order.{{footnote}}This definition is made through the ToVtlSubspace and ToVtlSpaceKey classes and/or the FromVtlSuperspace and FromVtlSpaceKey classes, depending on the direction of the mapping (“key” means “dimension”). The mapping of Dataflow subsets can be applied independently in the two directions, also according to different Dimensions. When no Dimension is declared for a given direction, it is assumed that the option of mapping different parts of a SDMX Dataflow to different VTL Data Sets is not used.{{/footnote}} Following the example above, imagine that the user declares the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY.
++* For a given [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], the user ([[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] definer) declares the DimensionComponents on which the (% style="color:#e74c3c" %)mapping(%%) will be based, in a given order.{{footnote}}This definition is made through the ToVtlSubspace and ToVtlSpaceKey classes and/or the FromVtlSuperspace and FromVtlSpaceKey classes, depending on the direction of the mapping (“key” means “dimension”). The mapping of Dataflow subsets can be applied independently in the two directions, also according to different Dimensions. When no Dimension is declared for a given direction, it is assumed that the option of mapping different parts of a SDMX Dataflow to different VTL Data Sets is not used.{{/footnote}} Following the example above, imagine that the user declares the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY.
  * The [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is given a name using a special notation also called “ordered concatenation” and composed of the following parts:
  ** The reference to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] (expressed according to the rules described in the previous paragraphs, i.e. URN, abbreviated URN or another alias); for example DF(1.0.0);
  ** a slash (“/”) as a separator;{{footnote}}As a consequence of this formalism, a slash in the name of the VTL Data Set assumes the specific meaning of separator between the name of the Dataflow and the values of some of its Dimensions.{{/footnote}}
  ** The reference to a specific part of the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] above, expressed as the concatenation of the values that the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DimensionComponents declared above must have, separated by dots (“.”) and written in the order in which these DimensionComponents are defined{{footnote}}This is the order in which the dimensions are defined in the ToVtlSpaceKey class or in the FromVtlSpaceKey class, depending on the direction of the mapping.{{/footnote}}. For example
--POPULATION.USA would mean that such a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is mapped to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] observations for which the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] //[[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]]// is equal to POPULATION and the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] //COUNTRY// is equal to USA.
++POPULATION.USA would mean that such a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is (% style="color:#e74c3c" %)mapped(%%) to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] observations for which the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] //[[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]]// is equal to POPULATION and the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] //COUNTRY// is equal to USA.
  In the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, this kind of [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] name must be referenced between single quotes because the slash (“/”) is not a regular character according to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] rules.
@@ -398,17 +398,17 @@
  In particular, this is the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that contains all the observations of the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF(1.0.0) for which //[[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]]// = POPULATION and //COUNTRY// = USA.
--Let us now analyse the different meaning of this kind of mapping in the two mapping directions, i.e. from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]].
++Let us now analyse the different meaning of this kind of (% style="color:#e74c3c" %)mapping(%%) in the two (% style="color:#e74c3c" %)mapping(%%) directions, i.e. from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]].
--As already said, the mapping from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] happens when the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are operand of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, instead the mapping from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] happens when the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that is result of Transformations{{footnote}}It should be remembered that, according to the VTL consistency rules, a given VTL dataset cannot be the result of more than one VTL Transformation.{{/footnote}} need to be treated as [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] objects. This kind of mapping can be applied independently in the two directions and the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] on which the mapping is based can be different in the two directions: these [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] are defined in the ToVtlSpaceKey and in the FromVtlSpaceKey classes respectively.
++As already said, the (% style="color:#e74c3c" %)mapping(%%) from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] happens when the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[dataflows>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are operand of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, instead the (% style="color:#e74c3c" %)mapping(%%) from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] happens when the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that is result of Transformations{{footnote}}It should be remembered that, according to the VTL consistency rules, a given VTL dataset cannot be the result of more than one VTL Transformation.{{/footnote}} need to be treated as [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] objects. This kind of (% style="color:#e74c3c" %)mapping(%%) can be applied independently in the two directions and the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] on which the (% style="color:#e74c3c" %)mapping(%%) is based can be different in the two directions: these [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] are defined in the ToVtlSpaceKey and in the FromVtlSpaceKey classes respectively.
--First, let us see what happens in the mapping direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]], i.e. when parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] (e.g. DF1(1.0.0)) need to be mapped to distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that are operand of some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations.
++First, let us see what happens in the (% style="color:#e74c3c" %)mapping(%%) direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]], i.e. when parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] (e.g. DF1(1.0.0)) need to be (% style="color:#e74c3c" %)mapped(%%) to distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that are operand of some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations.
  As already said, each [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is assumed to contain all the observations of the
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] having [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]]=//INDICATORvalue //and COUNTRY=// COUNTRYvalue//. For example, the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] ‘DF1(1.0.0)/POPULATION.USA’ would contain all the observations of DF1(1.0.0) having [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] = POPULATION and COUNTRY = USA.
--In order to obtain the data structure of these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] from the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] one, it is assumed that the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DimensionComponents on which the mapping is based are dropped, i.e. not maintained in the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure; this is possible because their values are fixed for each one of the invoked [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]{{footnote}}If these DimensionComponents would not be dropped, the various VTL Data Sets resulting from this kind of mapping would have non-matching values for the Identifiers corresponding to the mapping Dimensions (e.g. POPULATION and COUNTRY). As a consequence, taking into account that the typical binary VTL operations at dataset level (+, -, *, / and so on) are executed on the observations having matching values for the identifiers, it would not be possible to compose the resulting VTL datasets one another (e.g. it would not be possible to calculate the population ratio between USA and CANADA).{{/footnote}}. After that, the mapping method from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] specified for the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF1(1.0.0) is applied (i.e. basic, pivot …).
++In order to obtain the data structure of these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] from the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] one, it is assumed that the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] DimensionComponents on which the (% style="color:#e74c3c" %)mapping(%%) is based are dropped, i.e. not maintained in the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure; this is possible because their values are fixed for each one of the invoked [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]]{{footnote}}If these DimensionComponents would not be dropped, the various VTL Data Sets resulting from this kind of mapping would have non-matching values for the Identifiers corresponding to the mapping Dimensions (e.g. POPULATION and COUNTRY). As a consequence, taking into account that the typical binary VTL operations at dataset level (+, -, *, / and so on) are executed on the observations having matching values for the identifiers, it would not be possible to compose the resulting VTL datasets one another (e.g. it would not be possible to calculate the population ratio between USA and CANADA).{{/footnote}}. After that, the (% style="color:#e74c3c" %)mapping(%%) method from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] specified for the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF1(1.0.0) is applied (i.e. basic, pivot …).
  In the example above, for all the [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] of the kind
@@ -424,9 +424,9 @@
  >
  > … … …
--In fact the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operator “sub” has exactly the same behaviour. Therefore, mapping different parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to different [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] in the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] through the ordered concatenation notation is equivalent to a proper use of the operator “**sub**” on such a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]].{{footnote}}In case the ordered concatenation notation is used, the VTL Transformation described above, e.g. ‘DF1(1.0)/POPULATION.USA’ := DF1(1.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“USA”], is implicitly executed. In order to test the overall compliance of the VTL program to the VTL consistency rules, it has to be considered as part of the VTL program even if it is not explicitly coded.{{/footnote}}
++In fact the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operator “sub” has exactly the same behaviour. Therefore, (% style="color:#e74c3c" %)mapping(%%) different parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] to different [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] in the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] through the ordered concatenation notation is equivalent to a proper use of the operator “**sub**” on such a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]].{{footnote}}In case the ordered concatenation notation is used, the VTL Transformation described above, e.g. ‘DF1(1.0)/POPULATION.USA’ := DF1(1.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“USA”], is implicitly executed. In order to test the overall compliance of the VTL program to the VTL consistency rules, it has to be considered as part of the VTL program even if it is not explicitly coded.{{/footnote}}
--In the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] it is allowed to omit the value of one or more DimensionComponents on which the mapping is based, but maintaining all the separating dots (therefore it may happen to find two or more consecutive dots and dots in the beginning or in the end). The absence of value means that for the corresponding [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] all the values are kept and the [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] is not dropped.
++In the direction from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] it is allowed to omit the value of one or more DimensionComponents on which the (% style="color:#e74c3c" %)mapping(%%) is based, but maintaining all the separating dots (therefore it may happen to find two or more consecutive dots and dots in the beginning or in the end). The absence of value means that for the corresponding [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] all the values are kept and the [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] is not dropped.
  For example, ‘DF(1.0.0)/POPULATION.’ (note the dot in the end of the name) is the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] that contains all the observations of the [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF(1.0.0) for which //[[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]]// = POPULATION and COUNTRY = any value.
@@ -439,9 +439,9 @@
  Heterogeneous invocations of the same [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are allowed, i.e. omitting different [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] in different invocations.
--Let us now analyse the mapping direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]].
++Let us now analyse the (% style="color:#e74c3c" %)mapping(%%) direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]].
--In this situation, distinct parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are calculated as distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], under the [[constraint>>doc:sdmx:Glossary 2\.1.Constraint.WebHome]] that they must have the same [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure.
++In this situation, distinct parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] are calculated as distinct [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], under the (% style="color:#e74c3c" %)constraint(%%) that they must have the same [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure.
  For example, let us assume that the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] programmer wants to calculate the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] DF2(1.0.0) having the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] TIME_PERIOD, [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]], and COUNTRY and that such a programmer finds it convenient to calculate separately the parts of DF2(1.0.0) that have different combinations of values for [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY:
@@ -448,7 +448,7 @@
  * each part is calculated as a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] derived [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]], result of a dedicated [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformation;{{footnote}}If the whole DF2(1.0) is calculated by means of just one VTL Transformation, then the mapping between the SDMX Dataflow and the corresponding VTL dataset is one-to-one and this kind of mapping (one SDMX Dataflow to many VTL datasets) does not apply.{{/footnote}}
  * the data structure of all these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] has the TIME_PERIOD identifier and does not have the [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY identifiers.{{footnote}}This is possible as each VTL dataset corresponds to one particular combination of values of INDICATOR and COUNTRY.{{/footnote}}
--Under these hypothesis, such derived [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] can be mapped to DF2(1.0.0) by declaring the DimensionComponents [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY as (% style="color:#e74c3c" %)mapping(%%) [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]{{footnote}}The mapping dimensions are defined as FromVtlSpaceKeys of the FromVtlSuperSpace of the VtlDataflowMapping relevant to DF2(1.0).{{/footnote}}.
++Under these hypothesis, such derived [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] can be (% style="color:#e74c3c" %)mapped(%%) to DF2(1.0.0) by declaring the DimensionComponents [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY as (% style="color:#e74c3c" %)mapping(%%) [[dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]{{footnote}}The mapping dimensions are defined as FromVtlSpaceKeys of the FromVtlSuperSpace of the VtlDataflowMapping relevant to DF2(1.0).{{/footnote}}.
  The corresponding [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations, assuming that the result needs to be persistent, would be of this kind:{{footnote}}the symbol of the VTL persistent assignment is used (<-){{/footnote}}
@@ -462,7 +462,7 @@
  > ‘DF2(1.0.0)/POPGROWTH.CANADA’ <- expression22;
  > … … …
--As said, it is assumed that these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] derived [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] have the TIME_PERIOD as the only identifier. In the mapping from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to SMDX, the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY are added to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure on order to obtain the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] one, with the following values respectively:
++As said, it is assumed that these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] derived [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] have the TIME_PERIOD as the only identifier. In the (% style="color:#e74c3c" %)mapping(%%) from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to SMDX, the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY are added to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] data structure on order to obtain the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] one, with the following values respectively:
  > VTL dataset INDICATOR value COUNTRY value
  >
@@ -473,7 +473,7 @@
  > ‘DF2(1.0.0)/POPGROWTH.CANADA’ POPGROWTH CANADA
  > … … …
--It should be noted that the application of this many-to-one mapping from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] is equivalent to an appropriate sequence of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations. These use the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operator “calc” to add the proper [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] identifiers (in the example, [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY) and to assign to them the proper values and the operator “union” in order to obtain the final [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (in the example DF2(1.0.0)), that can be mapped oneto-one to the homonymous [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. Following the same example, these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations would be:
++It should be noted that the application of this many-to-one (% style="color:#e74c3c" %)mapping(%%) from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] is equivalent to an appropriate sequence of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations. These use the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operator “calc” to add the proper [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] identifiers (in the example, [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY) and to assign to them the proper values and the operator “union” in order to obtain the final [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (in the example DF2(1.0.0)), that can be (% style="color:#e74c3c" %)mapped(%%) oneto-one to the homonymous [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]. Following the same example, these [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformations would be:
  > DF2bis_GDPPERCAPITA_USA := ‘DF2(1.0.0)/GDPPERCAPITA.USA’ [calc identifier INDICATOR := ”GDPPERCAPITA”, identifier COUNTRY := ”USA”]; DF2bis_GDPPERCAPITA_CANADA := ‘DF2(1.0.0)/GDPPERCAPITA.CANADA’ [calc identifier INDICATOR:=”GDPPERCAPITA”, identifier COUNTRY:=”CANADA”];… … … DF2bis_POPGROWTH_USA := ‘DF2(1.0.0)/POPGROWTH.USA’ [calc identifier INDICATOR := ”POPGROWTH”, identifier COUNTRY := ”USA”]; DF2bis_POPGROWTH_CANADA’ := ‘DF2(1.0.0)/POPGROWTH.CANADA’ [calc identifier INDICATOR := ”POPGROWTH”, identifier COUNTRY := ”CANADA”];… … … DF2(1.0) <- UNION (DF2bis_GDPPERCAPITA_USA’, DF2bis_GDPPERCAPITA_CANADA’,
  > … ,
@@ -480,11 +480,11 @@
  > DF2bis_POPGROWTH_USA’, DF2bis_POPGROWTH_CANADA’
  > …);
--In other words, starting from the [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] explicitly calculated through [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] (in the example ‘DF2(1.0)/GDPPERCAPITA.USA’ and so on), the first step consists in calculating other (non-persistent) [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (in the example DF2bis_GDPPERCAPITA_USA and so on) by adding the identifiers [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY with the desired values (//INDICATORvalue// and //COUNTRYvalue)//. Finally, all these non-persistent [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] are united and give the final result DF2(1.0){{footnote}}The result is persistent in this example but it can be also non persistent if needed.{{/footnote}}, which can be mapped one-to-one to the homonymous [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] having the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] TIME_PERIOD, [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY.
++In other words, starting from the [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] explicitly calculated through [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] (in the example ‘DF2(1.0)/GDPPERCAPITA.USA’ and so on), the first step consists in calculating other (non-persistent) [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (in the example DF2bis_GDPPERCAPITA_USA and so on) by adding the identifiers [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY with the desired values (//INDICATORvalue// and //COUNTRYvalue)//. Finally, all these non-persistent [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] are united and give the final result DF2(1.0){{footnote}}The result is persistent in this example but it can be also non persistent if needed.{{/footnote}}, which can be (% style="color:#e74c3c" %)mapped(%%) one-to-one to the homonymous [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]] having the [[dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] TIME_PERIOD, [[INDICATOR>>doc:sdmx:Glossary 2\.1.Statistical indicator.WebHome]] and COUNTRY.
--Therefore, mapping different [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] having the same data structure to different parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], i.e. in the direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], through the ordered concatenation notation is equivalent to a proper use of the operators “calc” and “union” on such [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].{{footnote}}In case the ordered concatenation notation from VTL to SDMX is used, the set of Transformations described above is implicitly performed; therefore, in order to test the overall compliance of the VTL program to the VTL consistency rules, these implicit Transformations have to be considered as part of the VTL program even if they are not explicitly coded.{{/footnote}}{{footnote}}Through SDMX Constraints, it is possible to specify the values that a Component of a Dataflow can assume.{{/footnote}}
++Therefore, (% style="color:#e74c3c" %)mapping(%%) different [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] having the same data structure to different parts of a [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]], i.e. in the direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], through the ordered concatenation notation is equivalent to a proper use of the operators “calc” and “union” on such [[datasets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]].{{footnote}}In case the ordered concatenation notation from VTL to SDMX is used, the set of Transformations described above is implicitly performed; therefore, in order to test the overall compliance of the VTL program to the VTL consistency rules, these implicit Transformations have to be considered as part of the VTL program even if they are not explicitly coded.{{/footnote}}{{footnote}}Through SDMX Constraints, it is possible to specify the values that a Component of a Dataflow can assume.{{/footnote}}
--It is worth noting that in the direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] it is mandatory to specify the value for every [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] on which the mapping is based (in other word, in the name of the calculated [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is not possible to omit the value of some of the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]).
++It is worth noting that in the direction from [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] it is mandatory to specify the value for every [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] on which the (% style="color:#e74c3c" %)mapping(%%) is based (in other word, in the name of the calculated [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[dataset>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] is not possible to omit the value of some of the [[Dimensions>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]]).
  === 12.3.7 Mapping variables and value domains between VTL and SDMX ===
@@ -491,9 +491,9 @@
  With reference to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] “model for [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] and Value domains”, the following additional mappings have to be considered:
  (% style="width:706.294px" %)
--|(% style="width:257px" %)VTL|(% style="width:446px" %)SDMX
++|(% style="width:257px" %)[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]|(% style="width:446px" %)[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]
  |(% style="width:257px" %)**[[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]]**|(% style="width:446px" %)Although this abstraction exists in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], it does not have an explicit definition and correspond to a [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]] (either a DimensionComponent or a [[Measure>>doc:sdmx:Glossary 2\.1.Measure.WebHome]] or a DataAttribute) belonging to one specific [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]]^^43^^
--|(% style="width:257px" %)**Represented [[Variable>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]]**|(% style="width:446px" %)**[[Concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]]** with a definite [[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]
++|(% style="width:257px" %)**Represented [[Variable>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]]**|(% style="width:446px" %)(% style="color:#e74c3c" %)**Concept**(%%) with a definite [[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]
  |(% style="width:257px" %)**Value Domain**|(% style="width:446px" %)(((
  **[[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]** (see the Structure
  Pattern in the Base Package)
@@ -513,19 +513,19 @@
  The main difference between [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] relies on the fact that the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] for defining subsets of Value Domains do not exist in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], therefore the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] features for referring to predefined subsets are not available in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]. These [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] are the Value Domain Subset (or Set), either enumerated or described, the Set List (list of values belonging to enumerated subsets) and the [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]] (aimed at defining the set of values that the [[Component>>doc:sdmx:Glossary 2\.1.Component.WebHome]] of a [[Data Set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] can take, possibly a subset of the [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] of Value Domain).
--Another difference consists in the fact that all Value Domains are considered as identifiable objects in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] either if enumerated or not, while in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] the [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] (corresponding to a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] enumerated Value Domain) is identifiable, while the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] non-enumerated [[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (corresponding to a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] non-enumerated Value Domain) is not identifiable. As a consequence, the definition of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Rulesets, which in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] can refer either to enumerated or non-enumerated value domains, in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] can refer only to enumerated Value Domains (i.e. to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]]). As for the mapping between [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] and [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]], it should be noted that these [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] do not coincide perfectly. In fact, the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] are represented [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]], defined always on the same Value Domain (“[[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]” in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]) independently of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] / data structure in which they appear{{footnote}}By using represented variables, VTL can assume that data structures having the same variables as identifiers can be composed one another because the correspondent values can match.{{/footnote}}, while the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] can have different [[Representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] in different DataStructures.{{footnote}}A Concept becomes a Component in a DataStructureDefinition, and Components can have different LocalRepresentations in different DataStructureDefinitions, also overriding the (possible) base representation of the Concept.{{/footnote}} This means that one [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] can correspond to many [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]], one for each [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] the [[Concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] has.
++Another difference consists in the fact that all Value Domains are considered as identifiable objects in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] either if enumerated or not, while in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] the [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] (corresponding to a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] enumerated Value Domain) is identifiable, while the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] non-enumerated [[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (corresponding to a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] non-enumerated Value Domain) is not identifiable. As a consequence, the definition of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Rulesets, which in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] can refer either to enumerated or non-enumerated value domains, in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] can refer only to enumerated Value Domains (i.e. to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]]). As for the (% style="color:#e74c3c" %)mapping(%%) between [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] and [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concepts(%%), it should be noted that these [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] do not coincide perfectly. In fact, the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] are represented [[variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]], defined always on the same Value Domain (“[[Representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]” in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]) independently of the [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] / data structure in which they appear{{footnote}}By using represented variables, VTL can assume that data structures having the same variables as identifiers can be composed one another because the correspondent values can match.{{/footnote}}, while the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concepts(%%) can have different [[Representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] in different DataStructures.{{footnote}}A Concept becomes a Component in a DataStructureDefinition, and Components can have different LocalRepresentations in different DataStructureDefinitions, also overriding the (possible) base representation of the Concept.{{/footnote}} This means that one [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concept(%%) can correspond to many [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]], one for each [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] the (% style="color:#e74c3c" %)Concept(%%) has.
--Therefore, it is important to be aware that some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operations (for example the binary operations at [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] level) are consistent only if the [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] having the same names in the operated [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] have also the same [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (i.e. the same Value Domain as for [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]). For example, it is possible to obtain correct results from the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] expression
++Therefore, it is important to be aware that some [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operations (for example the binary operations at [[data set>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] (% style="color:#e74c3c" %)level(%%)) are consistent only if the [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] having the same names in the operated [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] [[Data Sets>>doc:sdmx:Glossary 2\.1.Data set.WebHome]] have also the same [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (i.e. the same Value Domain as for [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]). For example, it is possible to obtain correct results from the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] expression
  > DS_c := DS_a + DS_b (where DS_a, DS_b, DS_c are VTL Data Sets)
  if the matching [[components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] in DS_a and DS_b (e.g. ref_date, geo_area, [[sector>>doc:sdmx:Glossary 2\.1.Sector.WebHome]] …) refer to the same general [[representation>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. In simpler words, DS_a and DS_b must use the same values/[[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] (for ref_date, geo_area, [[sector>>doc:sdmx:Glossary 2\.1.Sector.WebHome]] … ), otherwise the relevant values would not match and the result of the operation would be wrong.
--As mentioned, the property above is not enforced by construction in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], and different [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of the same [[Concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] can be not compatible one another (for example, it may happen that geo_area is represented by ISO-alpha-3 [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in DS_a and by ISO alpha-2 [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in DS_b). Therefore, it will be up to the definer of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]
++As mentioned, the property above is not enforced by construction in [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]], and different [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of the same (% style="color:#e74c3c" %)Concept(%%) can be not compatible one another (for example, it may happen that geo_area is represented by ISO-alpha-3 [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in DS_a and by ISO alpha-2 [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in DS_b). Therefore, it will be up to the definer of [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]
--Transformations to ensure that the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] expressions are consistent with the actual [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of the correspondent [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]].
++Transformations to ensure that the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] expressions are consistent with the actual [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] of the correspondent [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concepts(%%).
--It remains up to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] definer also the assurance of the consistency between a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Ruleset defined on [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] and the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] on which the Ruleset is applied. In fact, a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Ruleset is expressed by means of the values of the [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] (i.e. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Concepts>>doc:sdmx:Glossary 2\.1.Concept.WebHome]]), i.e. assuming definite [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] for them (e.g. ISOalpha-3 for country). If the Ruleset is applied to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] that have the same name of the [[Concept>>doc:sdmx:Glossary 2\.1.Concept.WebHome]] they refer to but different [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (e.g. ISO-alpha-2 for country), the Ruleset cannot work properly.
++It remains up to the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]-[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] definer also the assurance of the consistency between a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Ruleset defined on [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] and the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] on which the Ruleset is applied. In fact, a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Ruleset is expressed by means of the values of the [[Variables>>doc:sdmx:Glossary 2\.1.Statistical variable.WebHome]] (i.e. [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] (% style="color:#e74c3c" %)Concepts(%%)), i.e. assuming definite [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] for them (e.g. ISOalpha-3 for country). If the Ruleset is applied to [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[Components>>doc:sdmx:Glossary 2\.1.Component.WebHome]] that have the same name of the (% style="color:#e74c3c" %)Concept(%%) they refer to but different [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] (e.g. ISO-alpha-2 for country), the Ruleset cannot work properly.
  == 12.4 Mapping between SDMX and VTL Data Types ==
@@ -537,7 +537,7 @@
  [[image:1750070288958-132.png]]
--**Figure 22 – VTL Data Types**
++**Figure 22 – [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Data Types**
  The [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] scalar types are in turn subdivided in basic scalar types, which are elementary (not defined in term of other data types) and Value Domain and Set scalar types, which are defined in terms of the basic scalar types.
@@ -545,7 +545,7 @@
  [[image:1750070310572-584.png]]
--**Figure 23 – VTL Basic Scalar Types**
++**Figure 23 – [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Basic Scalar Types**
  === 12.4.2 VTL basic scalar types and SDMX data types ===
@@ -559,7 +559,7 @@
  [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types are conceived instead to support the [[data exchange>>doc:sdmx:Glossary 2\.1.Data exchange.WebHome]], therefore they do have a format, which is known by the users and correspond, in [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] terms, to external [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]]. Therefore, for each [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar type there can be more [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types (the latter are explained in the section "General Notes for Implementers" of this document and are actually much more numerous than the former).
--The following paragraphs describe the mapping between the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types and the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar types. This mapping shall be presented in the two directions of possible conversion, i.e. from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and vice-versa.
++The following paragraphs describe the (% style="color:#e74c3c" %)mapping(%%) between the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types and the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar types. This (% style="color:#e74c3c" %)mapping(%%) shall be presented in the two directions of possible conversion, i.e. from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] and vice-versa.
  The conversion from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] happens when an [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] acts as inputs of a [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Transformation. As already said, in fact, at compile time the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] needs to know the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] type of the operands in order to check their compliance with the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] operators and at runtime it must convert the values from their external ([[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]]) [[representations>>doc:sdmx:Glossary 2\.1.Representation.WebHome]] to the corresponding internal ([[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]]) ones.
@@ -567,11 +567,11 @@
  === 12.4.3 Mapping SDMX data types to VTL basic scalar types ===
--The following table describes the default mapping for converting from the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar types.
++The following table describes the default (% style="color:#e74c3c" %)mapping(%%) for converting from the [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types to the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar types.
  (% style="width:583.294px" %)
--|(% style="width:360px" %)SDMX data type
--(BasicComponentDataType)|(% style="width:221px" %)Default VTL basic scalar type
++|(% style="width:360px" %)[[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data type
++(BasicComponentDataType)|(% style="width:221px" %)Default [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar type
  |(% style="width:360px" %)(((
  String
  (string allowing any character)
@@ -618,7 +618,7 @@
  )))|(% style="width:221px" %)number
  |(% style="width:360px" %)(((
  Boolean
--(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of
++(corresponds to the XML Schema xs:boolean datatype; support the mathematical (% style="color:#e74c3c" %)concept(%%) of
  binary-valued logic: {true, false})
  )))|(% style="width:221px" %)boolean
  |(% style="width:360px" %)(((
@@ -723,7 +723,7 @@
  |(% style="width:360px" %)IdentifiableReference|(% style="width:221px" %)Metadata type – not applicable
  |(% style="width:360px" %)DataSetReference|(% style="width:221px" %)Metadata type – not applicable
--**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
++**Figure 14 – Mappings from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Basic Scalar Types**
  When [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] takes in input [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], it is assumed that a type conversion according to the table above always happens. In case a different [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar type is desired, it can be achieved in the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] program taking in input the default [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar type above and applying to it the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] type conversion features (see the implicit and explicit type conversion and the "cast" operator in the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Reference Manual).
@@ -733,9 +733,9 @@
  (% style="width:748.294px" %)
  |(% style="width:164px" %)(((
--VTL basic scalar type
++[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar type
  )))|(% style="width:304px" %)(((
--Default SDMX data type
++Default [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data type
  (BasicComponentDataType)
  )))|(% style="width:277px" %)Default output format
  |(% style="width:164px" %)String|(% style="width:304px" %)String|(% style="width:277px" %)Like XML (xs:string)
@@ -753,7 +753,7 @@
  |(% style="width:164px" %)Duration|(% style="width:304px" %)Duration|(% style="width:277px" %)Like XML (xs:duration) PnYnMnDTnHnMnS
  |(% style="width:164px" %)Boolean|(% style="width:304px" %)Boolean|(% style="width:277px" %)Like XML (xs:boolean) with the values "true" or "false"
--**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
++**Figure 14 – Mappings from [[SDMX>>doc:sdmx:Glossary 2\.1.Statistical data and metadata exchange.WebHome]] data types to [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Basic Scalar Types**
  In case a different default conversion is desired, it can be achieved through the CustomTypeScheme and CustomType [[artefacts>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]] (see also the section Transformations and Expressions of the [[SDMX information model>>doc:sdmx:Glossary 2\.1.SDMX Information Model.WebHome]]).
@@ -760,7 +760,7 @@
  The custom output formats can be specified by means of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] formatting mask described in the section "Type Conversion and Formatting Mask" of the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] Reference Manual. Such a section describes the masks for the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] basic scalar types "number", "integer", "date", "time", "time_period" and "duration" and gives examples. As for the types "string" and "boolean" the [[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] conventions are extended with some other special characters as described in the following table.
  (% style="width:717.294px" %)
--|(% colspan="2" style="width:714px" %)VTL special characters for the formatting masks
++|(% colspan="2" style="width:714px" %)[[VTL>>doc:sdmx:Glossary 2\.1.Validation and transformation language.WebHome]] special characters for the formatting masks
  |(% colspan="2" style="width:714px" %)
  |(% colspan="2" style="width:714px" %)Number
  |(% style="width:122px" %)D|(% style="width:591px" %)one numeric digit (if the scientific notation is adopted, D is only for the mantissa)