Changes for page 12 Validation and Transformation Language (VTL)
Last modified by Helena on 2025/09/10 11:19
Summary
-
Page properties (1 modified, 0 added, 0 removed)
Details
- Page properties
-
- Content
-
... ... @@ -14,8 +14,10 @@ 14 14 15 15 The VTL language can be applied to SDMX artefacts by mapping the SDMX IM model artefacts to the model artefacts that VTL can manipulate{{footnote}}In this chapter, in order to distinguish VTL and SDMX model artefacts, the VTL ones are written in the Arial font while the SDMX ones in Courier New{{/footnote}}. Thus, the SDMX artefacts can be used in VTL as inputs and/or outputs of Transformations. It is important to be aware that the artefacts do not always have the same names in the SDMX and VTL IMs, nor do they always have the same meaning. The more evident example is given by the SDMX Dataset and the VTL "Data Set", which do not correspond one another: as a matter of fact, the VTL "Data Set" maps to the SDMX "Dataflow", while the SDMX "Dataset" has no explicit mapping to VTL (such an abstraction is not needed in the definition of VTL Transformations). A SDMX "Dataset", however, is an instance of a SDMX "Dataflow" and can be the artefact on which the VTL transformations are executed (i.e., the Transformations are defined on Dataflows and are applied to Dataflow instances that can be Datasets). 16 16 17 -The VTL programs (Transformation Schemes) are represented in SDMX through the TransformationScheme maintainable class which is composed of Transformation (nameable artefact). Each Transformation assigns the outcome of the evaluation of a VTL expression to a result.17 +The VTL programs (Transformation Schemes) are represented in SDMX through the TransformationScheme maintainable class which is composed of 18 18 19 +Transformation (nameable artefact). Each Transformation assigns the outcome of the evaluation of a VTL expression to a result. 20 + 19 19 This section does not explain the VTL language or any of the content published in the VTL guides. Rather, this is a description of how the VTL can be used in the SDMX context and applied to SDMX artefacts. 20 20 21 21 == 12.2 References to SDMX artefacts from VTL statements == ... ... @@ -26,8 +26,10 @@ 26 26 27 27 The alias of an SDMX artefact can be its URN (Universal Resource Name), an abbreviation of its URN or another user-defined name. 28 28 29 -In any case, the aliases used in the VTL Transformations have to be mapped to the SDMX artefacts through the VtlMappingScheme and VtlMapping classes (see the section of the SDMX IM relevant to the VTL). A VtlMapping allows specifying the aliases to be used in the VTL Transformations, Rulesets{{footnote}}See also the section "VTL-DL Rulesets" in the VTL Reference Manual.{{/footnote}} or User Defined Operators{{footnote}}The VTLMappings are used also for User Defined Operators (UDO). Although UDOs are envisaged to be defined on generic operands, so that the specific artefacts to be manipulated are passed as parameters at their invocation, it is also possible that an UDO invokes directly some specific SDMX artefacts. These SDMX artefacts have to be mapped to the corresponding aliases used in the definition of the UDO through the VtlMappingScheme and VtlMapping classes as well.{{/footnote}} to reference SDMX artefacts. A VtlMappingScheme is a container for zero or more VtlMapping.31 +In any case, the aliases used in the VTL Transformations have to be mapped to the 30 30 33 +SDMX artefacts through the VtlMappingScheme and VtlMapping classes (see the section of the SDMX IM relevant to the VTL). A VtlMapping allows specifying the aliases to be used in the VTL Transformations, Rulesets{{footnote}}See also the section "VTL-DL Rulesets" in the VTL Reference Manual.{{/footnote}} or User Defined Operators{{footnote}}The VTLMappings are used also for User Defined Operators (UDO). Although UDOs are envisaged to be defined on generic operands, so that the specific artefacts to be manipulated are passed as parameters at their invocation, it is also possible that an UDO invokes directly some specific SDMX artefacts. These SDMX artefacts have to be mapped to the corresponding aliases used in the definition of the UDO through the VtlMappingScheme and VtlMapping classes as well.{{/footnote}} to reference SDMX artefacts. A VtlMappingScheme is a container for zero or more VtlMapping. 34 + 31 31 The correspondence between an alias and a SDMX artefact must be one-to-one, meaning that a generic alias identifies one and just one SDMX artefact while a SDMX artefact is identified by one and just one alias. In other words, within a VtlMappingScheme an artefact can have just one alias and different artefacts cannot have the same alias. 32 32 33 33 The references through the URN and the abbreviated URN are described in the following paragraphs. ... ... @@ -78,7 +78,9 @@ 78 78 For example, by using the URN, the VTL Transformation that sums two SDMX Dataflows DF1 and DF2 and assigns the result to a third persistent Dataflow DFR, assuming that DF1, DF2 and DFR are the maintainedobject-id of the three Dataflows, that their version is 1.0.0 and their Agency is AG, would be written as{{footnote}}Since these references to SDMX objects include non-permitted characters as per the VTL ID notation, they need to be included between single quotes, according to the VTL rules for irregular names.{{/footnote}}: 79 79 80 80 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DFR(1.0.0)' <- 85 + 81 81 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DF1(1.0.0)' + 87 + 82 82 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DF2(1.0.0)' 83 83 84 84 === 12.2.3 Abbreviation of the URN === ... ... @@ -89,8 +89,8 @@ 89 89 90 90 * The SDMXprefix can be omitted for all the SDMX objects, because it is a prefixed string (urn:sdmx:org), always the same for SDMX objects. • The SDMX-IM-package-name** **can be omitted as well because it can be deduced from the class-name that follows it (the table of the SDMX-IM packages and classes that allows this deduction is in the SDMX 2.1 Standards - Section 5 - Registry Specifications, paragraph 6.2.3). In particular, considering the object classes of the artefacts that VTL can reference, the package is: 91 91 ** "datastructure" for the classes Dataflow, Dimension, TimeDimension, Measure, DataAttribute, o "conceptscheme" for the class Concept, o "codelist" for the class Codelist. 92 -* The class-name can be omitted as it can be deduced from the VTL invocation. In particular, starting from the VTL class of the invoked artefact (e.g. dataset, component, identifier, measure, attribute, variable, valuedomain), which is known given the syntax of the invoking VTL operator{{footnote}}For the syntax of the VTL operators see the VTL Reference Manual{{/footnote}}, the SDMX class can be deduced from the mapping rules between VTL and SDMX (see the section "Mapping between VTL and SDMX" hereinafter) {{footnote}}Incasetheinvokedartefactis a VTL component,which canbeinvokedonlywithintheinvocationof a VTL data set (SDMX Dataflow),the specific SDMX class-name(e.g. Dimension,TimeDimension,Measure or DataAttribute) canbe deduced fromthedatastructureof the SDMX Dataflow, whichthe componentbelongsto.{{/footnote}}.93 -* If the agency-id is not specified, it is assumed by default equal to the agency-id of the TransformationScheme, UserDefinedOperatorScheme or RulesetScheme from which the artefact is invoked. For example, the agencyid can be omitted if it is the same as the invoking TransformationScheme and cannot be omitted if the artefact comes from another agency {{footnote}}Ifthe Agency iscomposite(forexample AgencyA.Dept1.Unit2), the agencyis considered differentevenif onlypart of the compositenameisdifferent(forexample AgencyA.Dept1.Unit3is a differentAgency thanthe previous one). Moreovertheagency-id cannotbe omittedinpart(i.e., if a TransformationSchemeowned by AgencyA.Dept1.Unit2 referencesanartefact comingfrom AgencyA.Dept1.Unit3,the specificationoftheagency-id becomes mandatoryand mustbe complete, withoutomittingthepossiblyequal parts likeAgencyA.Dept1){{/footnote}}. Take also into account that, according to the VTL consistency rules, the agency of the result of a Transformation must be the same as its TransformationScheme, therefore the agency-id can be omitted for all the results (left part of Transformation statements).98 +* The class-name can be omitted as it can be deduced from the VTL invocation. In particular, starting from the VTL class of the invoked artefact (e.g. dataset, component, identifier, measure, attribute, variable, valuedomain), which is known given the syntax of the invoking VTL operator{{footnote}}For the syntax of the VTL operators see the VTL Reference Manual{{/footnote}}, the SDMX class can be deduced from the mapping rules between VTL and SDMX (see the section "Mapping between VTL and SDMX" hereinafter)^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^14^^>>path:#sdfootnote14sym||name="sdfootnote14anc"]](%%)^^. 99 +* If the agency-id is not specified, it is assumed by default equal to the agency-id of the TransformationScheme, UserDefinedOperatorScheme or RulesetScheme from which the artefact is invoked. For example, the agencyid can be omitted if it is the same as the invoking TransformationScheme and cannot be omitted if the artefact comes from another agency^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^15^^>>path:#sdfootnote15sym||name="sdfootnote15anc"]](%%)^^. Take also into account that, according to the VTL consistency rules, the agency of the result of a Transformation must be the same as its TransformationScheme, therefore the agency-id can be omitted for all the results (left part of Transformation statements). 94 94 * As for the maintainedobject-id, this is essential in some cases while in other cases it can be omitted: o if the referenced artefact is a Dataflow, which is a maintainable class, the maintainedobject-id is the dataflow-id and obviously cannot be omitted; 95 95 ** if the referenced artefact is a Dimension, TimeDimension, Measure, DataAttribute, which are not maintainable and belong to the DataStructure maintainable class, the maintainedobject-id is the dataStructure-id and can be omitted, given that these components are always invoked within the invocation of a Dataflow, whose dataStructure-id can be deduced from the SDMX structural definitions; 96 96 ** if the referenced artefact is a Concept, which is not maintainable and belong to the ConceptScheme maintainable class, the maintained object is the conceptScheme-id and cannot be omitted; ... ... @@ -103,7 +103,9 @@ 103 103 For example, the full formulation that uses the complete URN shown at the end of the previous paragraph: 104 104 105 105 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DFR(1.0.0)' := 112 + 106 106 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DF1(1.0.0)' + 114 + 107 107 'urn:sdmx:org.sdmx.infomodel.datastructure.Dataflow=AG:DF2(1.0.0)' 108 108 109 109 by omitting all the non-essential parts would become simply: ... ... @@ -110,11 +110,11 @@ 110 110 111 111 DFR := DF1 + DF2 112 112 113 -The references to the Codelists can be simplified similarly. For example, given the non-abbreviated reference to the Codelist AG:CL_FREQ(1.0.0), which is {{footnote}}Singlequotes areneededbecausethisreferenceisnotaVTLregular name.{{/footnote}}:121 +The references to the Codelists can be simplified similarly. For example, given the non-abbreviated reference to the Codelist AG:CL_FREQ(1.0.0), which is^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^16^^>>path:#sdfootnote16sym||name="sdfootnote16anc"]](%%)^^: 114 114 115 115 'urn:sdmx:org.sdmx.infomodel.codelist.Codelist=AG:CL_FREQ(1.0.0)' 116 116 117 -if the Codelist is referenced from a RulesetScheme belonging to the agency AG, omitting all the optional parts, the abbreviated reference would become simply {{footnote}}Single quotes are not needed in this case because CL_FREQ is a VTL regular name.{{/footnote}}:125 +if the Codelist is referenced from a RulesetScheme belonging to the agency AG, omitting all the optional parts, the abbreviated reference would become simply^^19^^: 118 118 119 119 CL_FREQ 120 120 ... ... @@ -128,7 +128,7 @@ 128 128 129 129 SECTOR 130 130 131 -For example, the Transformation for renaming the component SECTOR of the Dataflow DF1 into SEC can be written as {{footnote}}Theresult DFR(1.0.0)isbe equal to DF1(1.0.0) save that thecomponentSECTORiscalledSEC{{/footnote}}:139 +For example, the Transformation for renaming the component SECTOR of the Dataflow DF1 into SEC can be written as^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^17^^>>path:#sdfootnote17sym||name="sdfootnote17anc"]](%%)^^: 132 132 133 133 'DFR(1.0.0)' := 'DF1(1.0.0)' [rename SECTOR to SEC] 134 134 ... ... @@ -160,9 +160,9 @@ 160 160 161 161 The VTL Rulesets have a signature, in which the Value Domains or the Variables on which the Ruleset is defined are declared, and a body, which contains the Rules. 162 162 163 -In the signature, given the mapping between VTL and SDMX better described in the following paragraphs, a reference to a VTL Value Domain becomes a reference to a SDMX Codelist, while a reference to a VTL Represented Variable becomes a reference to a SDMX Concept, assuming for it a definite representation {{footnote}}Rulesetsofthiskind cannotbereusedwhen thereferencedConcepthasadifferentrepresentation.{{/footnote}}.171 +In the signature, given the mapping between VTL and SDMX better described in the following paragraphs, a reference to a VTL Value Domain becomes a reference to a SDMX Codelist, while a reference to a VTL Represented Variable becomes a reference to a SDMX Concept, assuming for it a definite representation^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^18^^>>path:#sdfootnote18sym||name="sdfootnote18anc"]](%%)^^. 164 164 165 -In general, for referencing SDMX Codelists and Concepts, the conventions described in the previous paragraphs apply. In the Ruleset syntax, the elements that reference SDMX artefacts are called "valueDomain" and "variable" for the Datapoint Rulesets and "ruleValueDomain", "ruleVariable", "condValueDomain" "condVariable" for the Hierarchical Rulesets). The syntax of the Ruleset signature allows also to define aliases of the elements above, these aliases are valid only within the specific Ruleset definition statement and cannot be mapped to SDMX. {{footnote}}Seealsothesection"VTL-DL Rulesets"in theVTL ReferenceManual.{{/footnote}}173 +In general, for referencing SDMX Codelists and Concepts, the conventions described in the previous paragraphs apply. In the Ruleset syntax, the elements that reference SDMX artefacts are called "valueDomain" and "variable" for the Datapoint Rulesets and "ruleValueDomain", "ruleVariable", "condValueDomain" "condVariable" for the Hierarchical Rulesets). The syntax of the Ruleset signature allows also to define aliases of the elements above, these aliases are valid only within the specific Ruleset definition statement and cannot be mapped to SDMX.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^19^^>>path:#sdfootnote19sym||name="sdfootnote19anc"]](%%)^^ 166 166 167 167 In the body of the Rulesets, the Codes and in general all the Values can be written without any other specification, because the artefact, which the Values are referred (Codelist, Concept) to can be deduced from the Ruleset signature. 168 168 ... ... @@ -174,15 +174,15 @@ 174 174 175 175 Every time a SDMX object is referenced in a VTL Transformation as an input operand, there is the need to generate a VTL definition of the object, so that the VTL operations can take place. This can be made starting from the SDMX definition and applying a SDMX-VTL mapping method in the direction from SDMX to VTL. The possible mapping methods from SDMX to VTL are described in the following paragraphs and are conceived to allow the automatic deduction of the VTL definition of the object from the knowledge of the SDMX definition. 176 176 177 -In the opposite direction, every time an object calculated by means of VTL must be treated as a SDMX object (for example for exchanging it through SDMX), there is the need of a SDMX definition of the object, so that the SDMX operations can take place. The SDMX definition is needed for the VTL objects for which a SDMX use is envisaged {{footnote}}Ifacalculated artefact ispersistent,itneedsa persistentdefinition,i.e. a SDMX definition ina SDMXenvironment. Inaddition,possiblecalculatedartefact that arenotpersistentmay requireaSDMX definition, forexamplewhentheresult ofanon-persistent calculation is disseminated through SDMX tools (likean inquirytool).{{/footnote}}.185 +In the opposite direction, every time an object calculated by means of VTL must be treated as a SDMX object (for example for exchanging it through SDMX), there is the need of a SDMX definition of the object, so that the SDMX operations can take place. The SDMX definition is needed for the VTL objects for which a SDMX use is envisaged^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^20^^>>path:#sdfootnote20sym||name="sdfootnote20anc"]](%%)^^. 178 178 179 179 The mapping methods from VTL to SDMX are described in the following paragraphs as well, however they do not allow the complete SDMX definition to be automatically deduced from the VTL definition, more than all because the former typically contains additional information in respect to the latter. For example, the definition of a SDMX DSD includes also some mandatory information not available in VTL (like the concept scheme to which the SDMX components refer, the ‘usage’ and ‘attributeRelationship’ for the DataAttributes and so on). Therefore the mapping methods from VTL to SDMX provide only a general guidance for generating SDMX definitions properly starting from the information available in VTL, independently of how the SDMX definition it is actually generated (manually, automatically or part and part). 180 180 181 181 === 12.3.2 General mapping of VTL and SDMX data structures === 182 182 183 -This section makes reference to the VTL "Model for data and their structure" {{footnote}}See theVTL2.0UserManual{{/footnote}}and the correspondent SDMX "Data Structure Definition"{{footnote}}SeetheSDMX StandardsSection2 – InformationModel{{/footnote}}.191 +This section makes reference to the VTL "Model for data and their structure"^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^21^^>>path:#sdfootnote21sym||name="sdfootnote21anc"]](%%)^^ and the correspondent SDMX "Data Structure Definition"^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^22^^>>path:#sdfootnote22sym||name="sdfootnote22anc"]](%%)^^. 184 184 185 -The main type of artefact that the VTL can manipulate is the VTL Data Set, which in general is mapped to the SDMX Dataflow. This means that a VTL Transformation, in the SDMX context, expresses the algorithm for calculating a derived Dataflow starting from some already existing Dataflows (either collected or derived). {{footnote}}BesidesthemappingbetweenoneSDMX Dataflow andone VTL Data Set,itisalso possibleto mapdistinctparts ofaSDMX Dataflowto different VTL DataSet, asexplainedinafollowingparagraph.{{/footnote}}193 +The main type of artefact that the VTL can manipulate is the VTL Data Set, which in general is mapped to the SDMX Dataflow. This means that a VTL Transformation, in the SDMX context, expresses the algorithm for calculating a derived Dataflow starting from some already existing Dataflows (either collected or derived).^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^23^^>>path:#sdfootnote23sym||name="sdfootnote23anc"]](%%)^^ 186 186 187 187 While the VTL Transformations are defined in term of Dataflow definitions, they are assumed to be executed on instances of such Dataflows, provided at runtime to the VTL engine (the mechanism for identifying the instances to be processed are not part of the VTL specifications and depend on the implementation of the VTL-based systems). As already said, the SDMX Datasets are instances of SDMX Dataflows, therefore a VTL Transformation defined on some SDMX Dataflows can be applied on some corresponding SDMX Datasets. 188 188 ... ... @@ -198,56 +198,70 @@ 198 198 199 199 === 12.3.3 Mapping from SDMX to VTL data structures === 200 200 201 - ====12.3.3.1 Basic Mapping====209 +**12.3.3.1 Basic Mapping** 202 202 203 203 The main mapping method from SDMX to VTL is called **Basic **mapping. This is considered as the default mapping method and is applied unless a different method is specified through the VtlMappingScheme and VtlDataflowMapping classes. When transforming **from SDMX to VTL**, this method consists in leaving the components unchanged and maintaining their names and roles, according to the following table: 204 204 205 -(% style="width:529.294px" %) 206 -|(% style="width:151px" %)**SDMX**|(% style="width:375px" %)**VTL** 207 -|(% style="width:151px" %)Dimension|(% style="width:375px" %)(Simple) Identifier 208 -|(% style="width:151px" %)TimeDimension|(% style="width:375px" %)(Time) Identifier 209 -|(% style="width:151px" %)Measure|(% style="width:375px" %)Measure 210 -|(% style="width:151px" %)DataAttribute|(% style="width:375px" %)Attribute 213 +|**SDMX**|**VTL** 214 +|Dimension|(Simple) Identifier 215 +|TimeDimension|(Time) Identifier 211 211 217 +[[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_59eee18f.gif||alt="Shape4" height="1" width="192"]] 218 + 219 +|Measure|Measure 220 +|DataAttribute|Attribute 221 + 212 212 The SDMX DataAttributes, in VTL they are all considered "at data point / observation level" (i.e. dependent on all the VTL Identifiers), because VTL does not have the SDMX AttributeRelationships, which defines the construct to which the DataAttribute is related (e.g. observation, dimension or set or group of dimensions, whole data set). 213 213 214 -With the Basic mapping, one SDMX observation {{footnote}}Herean SDMX observation is meant to correspond to one combination of values of the DimensionComponents.{{/footnote}}generates one VTL data point.224 +With the Basic mapping, one SDMX observation^^27^^ generates one VTL data point. 215 215 216 - ====12.3.3.2 Pivot Mapping====226 +**12.3.3.2 Pivot Mapping** 217 217 218 218 An alternative mapping method from SDMX to VTL is the **Pivot **mapping, which makes sense and is different from the Basic method only for the SDMX data structures that contain a Dimension that plays the role of measure dimension (like in SDMX 2.1) and just one Measure. Through this method, these structures can be mapped to multimeasure VTL data structures. Besides that, a user may choose to use any Dimension acting as a list of Measures (e.g., a Dimension with indicators), either by considering the “Measure” role of a Dimension, or at will using any coded Dimension. Of course, in SDMX 3.0, this can only work when only one Measure is defined in the DSD. 219 219 220 -In SDMX 2.1 the MeasureDimension was a subclass of DimensionComponent like Dimension and TimeDimension. In the current SDMX version, this subclass does not exist anymore, however a Dimension can have the role of measure dimension (i.e. a Dimension that contributes to the identification of the measures). In SDMX 2.1 a DataStructure could have zero or one MeasureDimensions, in the current version of the standard, from zero to many Dimension may have the role of measure dimension. Hereinafter a Dimension that plays the role of measure dimension is referenced for simplicity as “MeasureDimension“, i.e. maintaining the capital letters and the courier font even if the MeasureDimension is not anymore a class in the SDMX Information Model of the current SDMX version. For the sake of simplicity, the description below considers just one Dimension having the role of MeasureDimension (i.e., the more simple and common case). Nevertheless, it maintains its validity also if in the DataStructure there are more dimension with the role of MeasureDimensions: in this case what is said about the MeasureDimension must be applied to the combination of all the MeasureDimensions considered as a joint variable{{footnote}}E.g., if in the data structure there exist 3 Dimensions C,D,E having the role of MeasureDimension, they should be considered as a joint MeasureDimension Z=(C,D,E); therefore when the description says “each possible value Cj of the MeasureDimension …” it means “each possible combination of values (Cj, Dk, Ew) of the joint MeasureDimension Z=(C,D,E)”.{{/footnote}}.230 +In SDMX 2.1 the MeasureDimension was a subclass of DimensionComponent like Dimension and TimeDimension. In the current SDMX version, this subclass does not exist anymore, however a Dimension can have the role of measure dimension (i.e. a Dimension that contributes to the identification of the measures). In SDMX 2.1 a DataStructure could have zero or one MeasureDimensions, in the current version of the standard, from zero to many Dimension may have the role of measure dimension. Hereinafter a Dimension that plays the role of measure dimension is referenced for simplicity as “MeasureDimension“, i.e. maintaining the capital letters and the courier font even if the MeasureDimension is not anymore a class in the SDMX Information Model of the current SDMX version. For the sake of simplicity, the description below considers just one Dimension having the role of MeasureDimension (i.e., the more simple and common case). Nevertheless, it maintains its validity also if in the DataStructure there are more dimension with the role of MeasureDimensions: in this case what is said about the MeasureDimension must be applied to the combination of all the 221 221 232 +MeasureDimensions considered as a joint variable^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^24^^>>path:#sdfootnote24sym||name="sdfootnote24anc"]](%%)^^. 233 + 222 222 Among other things, the Pivot method provides also backward compatibility with the SDMX 2.1 data structures that contained a MeasureDimension. 223 223 224 224 If applied to SDMX structures that do not contain any MeasureDimension, this method behaves like the Basic mapping (see the previous paragraph). 225 225 226 -Here an SDMX observation is meant to correspond to one combination of values of the DimensionComponents. 238 +^^27^^ Here an SDMX observation is meant to correspond to one combination of values of the DimensionComponents. 227 227 228 228 The SDMX structures that contain a MeasureDimension are mapped as described below (this mapping is equivalent to a pivoting operation): 229 229 230 230 * A SDMX simple dimension becomes a VTL (simple) identifier and a SDMX TimeDimension becomes a VTL (time) identifier; 231 -* Each possible Code Cj of the SDMX MeasureDimension is mapped to a VTL Measure, having the same name as the SDMX Code (i.e. Cj); the VTL Measure Cj is a new VTL component even if the SDMX data structure has not such a Component; 243 +* Each possible Code Cj of the SDMX MeasureDimension is mapped to a VTL Measure, having the same name as the SDMX Code (i.e. Cj); the VTL Measure Cj is a new VTL component even if the SDMX data structure has not such a 244 + 245 +Component; 246 + 232 232 * The SDMX MeasureDimension is not mapped to VTL (it disappears in the VTL Data Structure); 233 233 * The SDMX Measure is not mapped to VTL as well (it disappears in the VTL Data Structure); 234 234 * An SDMX DataAttribute is mapped in different ways according to its AttributeRelationship: 235 -** If, according to the SDMX AttributeRelationship, the values of the DataAttribute do not depend on the values of the MeasureDimension, the SDMX DataAttribute becomes a VTL Attribute having the same name. This happens if the AttributeRelationship is not specified (i.e. the DataAttribute does not depend on any DimensionComponent and therefore is at data set level), or if it refers to a set (or a group) of dimensions which does not include the MeasureDimension; 250 +** If, according to the SDMX AttributeRelationship, the values of the DataAttribute do not depend on the values of the MeasureDimension, the SDMX DataAttribute becomes a VTL Attribute having the same name. This happens if the 251 + 252 +AttributeRelationship is not specified (i.e. the DataAttribute does not depend on any DimensionComponent and therefore is at data set level), or if it refers to a set (or a group) of dimensions which does not include the MeasureDimension; 253 + 254 +* 236 236 ** Otherwise, if, according to the SDMX AttributeRelationship, the values of the DataAttribute depend on the MeasureDimension, the SDMX DataAttribute is mapped to one VTL Attribute for each possible Code of the SDMX MeasureDimension. By default, the names of the VTL Attributes are obtained by concatenating the name of the SDMX DataAttribute and the names of the correspondent Code of the MeasureDimension separated by underscore. For example, if the SDMX DataAttribute is named DA and the possible Codes of the SDMX MeasureDimension are named C1, C2, …, Cn, then the corresponding VTL Attributes will be named DA_C1, DA_C2, …, DA_Cn (if different names are desired, they can be achieved afterwards by renaming the Attributes through VTL operators). 237 237 ** Like in the Basic mapping, the resulting VTL Attributes are considered as dependent on all the VTL identifiers (i.e. "at data point / observation level"), because VTL does not have the SDMX notion of Attribute Relationship. 238 238 239 239 The summary mapping table of the "pivot" mapping from SDMX to VTL for the SDMX data structures that contain a MeasureDimension is the following: 240 240 241 -(% style="width:769.294px" %) 242 -|(% style="width:401px" %)**SDMX**|(% style="width:366px" %)**VTL** 243 -|(% style="width:401px" %)Dimension|(% style="width:366px" %)(Simple) Identifier 244 -|(% style="width:401px" %)TimeDimension|(% style="width:366px" %)(Time) Identifier 245 -|(% style="width:401px" %)MeasureDimension & one Measure|(% style="width:366px" %)((( 246 -One Measure for each Code of the SDMX MeasureDimension 260 +|**SDMX**|**VTL** 261 +|Dimension|(Simple) Identifier 262 +|TimeDimension|(Time) Identifier 263 +|MeasureDimension & one Measure|((( 264 +One Measure for each Code of the 265 + 266 +SDMX MeasureDimension 247 247 ))) 248 -|(% style="width:401px" %)DataAttribute not depending on the MeasureDimension|(% style="width:366px" %)Attribute 249 -|(% style="width:401px" %)DataAttribute depending on the MeasureDimension|(% style="width:366px" %)((( 250 -One Attribute for each Code of the SDMX MeasureDimension 268 +|DataAttribute not depending on the MeasureDimension|Attribute 269 +|DataAttribute depending on the MeasureDimension|((( 270 +One Attribute for each Code of the 271 + 272 +SDMX MeasureDimension 251 251 ))) 252 252 253 253 Using this mapping method, the components of the data structure can change in the conversion from SDMX to VTL and it must be taken into account that the VTL statements can reference only the components of the resulting VTL data structure. ... ... @@ -262,7 +262,7 @@ 262 262 * The value of the Measure of the SDMX observation belonging to the set above and having MeasureDimension=Cj becomes the value of the VTL Measure Cj 263 263 * For the SDMX DataAttributes depending on the MeasureDimension, the value of the DataAttribute DA of the SDMX observation belonging to the set above and having MeasureDimension=Cj becomes the value of the VTL Attribute DA_Cj 264 264 265 - ====12.3.3.3 From SDMX DataAttributes to VTL Measures====287 +**12.3.3.3 From SDMX DataAttributes to VTL Measures** 266 266 267 267 * In some cases, it may happen that the DataAttributes of the SDMX DataStructure need to be managed as Measures in VTL. Therefore, a variant of both the methods above consists in transforming all the SDMX DataAttributes in VTL Measures. When DataAttributes are converted to Measures, the two methods above are called Basic_A2M and Pivot_A2M (the suffix "A2M" stands for Attributes to Measures). Obviously, the resulting VTL data structure is, in general, multi-measure and does not contain 268 268 ... ... @@ -274,7 +274,7 @@ 274 274 275 275 === 12.3.4 Mapping from VTL to SDMX data structures === 276 276 277 - ====12.3.4.1 Basic Mapping====299 +**12.3.4.1 Basic Mapping** 278 278 279 279 The main mapping method **from VTL to SDMX** is called **Basic **mapping as well. 280 280 ... ... @@ -284,12 +284,11 @@ 284 284 285 285 Mapping table: 286 286 287 -(% style="width:667.294px" %) 288 -|(% style="width:272px" %)**VTL**|(% style="width:392px" %)**SDMX** 289 -|(% style="width:272px" %)(Simple) Identifier|(% style="width:392px" %)Dimension 290 -|(% style="width:272px" %)(Time) Identifier|(% style="width:392px" %)TimeDimension 291 -|(% style="width:272px" %)Measure|(% style="width:392px" %)Measure 292 -|(% style="width:272px" %)Attribute|(% style="width:392px" %)DataAttribute 309 +|**VTL**|**SDMX** 310 +|(Simple) Identifier|Dimension 311 +|(Time) Identifier|TimeDimension 312 +|Measure|Measure 313 +|Attribute|DataAttribute 293 293 294 294 If the distinction between simple identifier and time identifier is not maintained in the VTL environment, the classification between Dimension and TimeDimension exists only in SDMX, as declared in the relevant DataStructureDefinition. 295 295 ... ... @@ -299,7 +299,7 @@ 299 299 300 300 As said, the resulting SDMX definitions must be compliant with the SDMX consistency rules. For example, the SDMX DSD must have the AttributeRelationship for the DataAttributes, which does not exist in VTL. 301 301 302 - ====12.3.4.2 Unpivot Mapping====323 +**12.3.4.2 Unpivot Mapping** 303 303 304 304 An alternative mapping method from VTL to SDMX is the **Unpivot **mapping. 305 305 ... ... @@ -323,12 +323,11 @@ 323 323 324 324 The summary mapping table of the **unpivot** mapping method is the following: 325 325 326 -(% style="width:994.294px" %) 327 -|(% style="width:306px" %)**VTL**|(% style="width:684px" %)**SDMX** 328 -|(% style="width:306px" %)(Simple) Identifier|(% style="width:684px" %)Dimension 329 -|(% style="width:306px" %)(Time) Identifier|(% style="width:684px" %)TimeDimension 330 -|(% style="width:306px" %)All Measure Components|(% style="width:684px" %)MeasureDimension (having one Code for each VTL measure component) & one Measure 331 -|(% style="width:306px" %)Attribute|(% style="width:684px" %)DataAttribute depending on all SDMX Dimensions including the TimeDimension and except the MeasureDimension 347 +|**VTL**|**SDMX** 348 +|(Simple) Identifier|Dimension 349 +|(Time) Identifier|TimeDimension 350 +|All Measure Components|MeasureDimension (having one Code for each VTL measure component) & one Measure 351 +|Attribute|DataAttribute depending on all SDMX Dimensions including the TimeDimension and except the MeasureDimension 332 332 333 333 At observation / data point level: 334 334 ... ... @@ -342,7 +342,7 @@ 342 342 343 343 In any case, the resulting SDMX definitions must be compliant with the SDMX consistency rules. For example, the possible Codes of the SDMX MeasureDimension need to be listed in a SDMX Codelist, with proper id, agency and version; moreover, the SDMX DSD must have the AttributeRelationship for the DataAttributes, which does not exist in VTL. 344 344 345 - ====12.3.4.3 From VTL Measures to SDMX Data Attributes====365 +**12.3.4.3 From VTL Measures to SDMX Data Attributes** 346 346 347 347 More than all for the multi-measure VTL structures (having more than one Measure Component), it may happen that the Measures of the VTL Data Structure need to be managed as DataAttributes in SDMX. Therefore, a third mapping method consists in transforming some VTL measures in a corresponding SDMX Measures and all the other VTL Measures in SDMX DataAttributes. This method is called M2A (“M2A” stands for “Measures to DataAttributes”). 348 348 ... ... @@ -350,13 +350,12 @@ 350 350 351 351 The mapping table is the following: 352 352 353 -(% style="width:689.294px" %) 354 -|(% style="width:344px" %)VTL|(% style="width:341px" %)SDMX 355 -|(% style="width:344px" %)(Simple) Identifier|(% style="width:341px" %)Dimension 356 -|(% style="width:344px" %)(Time) Identifier|(% style="width:341px" %)TimeDimension 357 -|(% style="width:344px" %)Some Measures|(% style="width:341px" %)Measure 358 -|(% style="width:344px" %)Other Measures|(% style="width:341px" %)DataAttribute 359 -|(% style="width:344px" %)Attribute|(% style="width:341px" %)DataAttribute 373 +|VTL|SDMX 374 +|(Simple) Identifier|Dimension 375 +|(Time) Identifier|TimeDimension 376 +|Some Measures|Measure 377 +|Other Measures|DataAttribute 378 +|Attribute|DataAttribute 360 360 361 361 Even in this case, the resulting SDMX definitions must be compliant with the SDMX consistency rules. For example, the SDMX DSD must have the attributeRelationship for the DataAttributes, which does not exist in VTL. 362 362 ... ... @@ -374,20 +374,20 @@ 374 374 375 375 Until now it has been assumed to map one SMDX Dataflow to one VTL Data Set and vice-versa. This mapping one-to-one is not mandatory according to VTL because a VTL Data Set 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 or storage (see VTL 2.0 User Manual page 24), therefore a SDMX Dataflow can be seen either as a unique set of data observations (corresponding to one VTL Data Set) or as the union of many sets of data observations (each one corresponding to a distinct VTL Data Set). 376 376 377 -As a matter of fact, in some cases it can be useful to define VTL operations involving definite parts of a SDMX Dataflow instead than the whole. {{footnote}}Atypicalexample of thiskindisthevalidation,and moreingeneral themanipulation,ofindividualtimeseries belongingto thesame Dataflow,identifiable through the DimensionComponents of theDataflowexcept the TimeDimension. Thecodingof thesekind of operationsmight be simplified by mappingdistincttimeseries(i.e. differentpartsofa SDMX Dataflow) todistinctVTL Data Sets.{{/footnote}}396 +As a matter of fact, in some cases it can be useful to define VTL operations involving definite parts of a SDMX Dataflow instead than the whole.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^25^^>>path:#sdfootnote25sym||name="sdfootnote25anc"]](%%)^^ 378 378 379 -Therefore, in order to make the coding of VTL operations simpler when applied on parts of SDMX Dataflows, it is allowed to map distinct parts of a SDMX Dataflow to distinct VTL Data Sets according to the following rules and conventions. This kind of mapping is possible both from SDMX to VTL and from VTL to SDMX, as better explained below. {{footnote}}Pleasenotethat thiskind of mappingis onlyanoptionatdisposalof the definerof VTL Transformations;infactit remainsalways possible to manipulatetheneeded parts of SDMX Dataflows by meansof VTL operators(e.g. “sub”, “filter”, “calc”, “union”…), maintainingamappingone-to-one betweenSDMX Dataflowsand VTL Data Sets.{{/footnote}}398 +Therefore, in order to make the coding of VTL operations simpler when applied on parts of SDMX Dataflows, it is allowed to map distinct parts of a SDMX Dataflow to distinct VTL Data Sets according to the following rules and conventions. This kind of mapping is possible both from SDMX to VTL and from VTL to SDMX, as better explained below.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^26^^>>path:#sdfootnote26sym||name="sdfootnote26anc"]](%%)^^ 380 380 381 381 Given a SDMX Dataflow and some predefined Dimensions of its DataStructure, it is allowed to map the subsets of observations that have the same combination of values for such Dimensions to correspondent VTL datasets. 382 382 383 383 For example, assuming that the SDMX Dataflow DF1(1.0.0) has the Dimensions INDICATOR, TIME_PERIOD and COUNTRY, and that the user declares the Dimensions INDICATOR and COUNTRY as basis for the mapping (i.e. the mapping dimensions): the observations that have the same values for INDICATOR and COUNTRY would be mapped to the same VTL dataset (and vice-versa). In practice, this kind mapping is obtained like follows: 384 384 385 -* For a given SDMX Dataflow, the user (VTL definer) declares the DimensionComponents on which the mapping will be based, in a given order. {{footnote}}Thisdefinitionis madethrough theToVtlSubspace and ToVtlSpaceKey classes and/ortheFromVtlSuperspace and FromVtlSpaceKey classes, dependingon the directionofthemapping (“key”means “dimension”). The mapping of Dataflow subsets canbeappliedindependentlyinthe two directions,also accordingto differentDimensions.When no Dimension is declared foragivendirection,itis assumed that the optionof mappingdifferentpartsofa SDMX Dataflow todifferentVTL Data Sets isnotused.{{/footnote}}Following the example above, imagine that the user declares the Dimensions INDICATOR and COUNTRY.404 +* For a given SDMX Dataflow, the user (VTL definer) declares the DimensionComponents on which the mapping will be based, in a given order.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^27^^>>path:#sdfootnote27sym||name="sdfootnote27anc"]](%%)^^ Following the example above, imagine that the user declares the Dimensions INDICATOR and COUNTRY. 386 386 * The VTL Data Set is given a name using a special notation also called “ordered concatenation” and composed of the following parts: 387 387 ** The reference to the SDMX Dataflow (expressed according to the rules described in the previous paragraphs, i.e. URN, abbreviated URN or another alias); for example DF(1.0.0); 388 -** a slash (“/”) as a separator; {{footnote}}Asaconsequence ofthis formalism,aslashin thenameoftheVTL DataSetassumesthespecific meaningof separatorbetweenthenameoftheDataflow andthevaluesofsomeof itsDimensions.{{/footnote}}407 +** a slash (“/”) as a separator; ^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^28^^>>path:#sdfootnote28sym||name="sdfootnote28anc"]](%%)^^ 389 389 390 -The reference to a specific part of the SDMX Dataflow above, expressed as the concatenation of the values that the SDMX DimensionComponents declared above must have, separated by dots (“.”) and written in the order in which these DimensionComponents are defined {{footnote}}Thisistheorderin whichthedimensionsare definedin theToVtlSpaceKey classorin theFromVtlSpaceKey class,dependingonthedirectionofthemapping.{{/footnote}}. For example POPULATION.USA would mean that such a VTL Data Set is mapped to the SDMX observations for which the dimension //INDICATOR// is equal to POPULATION and the dimension //COUNTRY// is equal to USA.409 +The reference to a specific part of the SDMX Dataflow above, expressed as the concatenation of the values that the SDMX DimensionComponents declared above must have, separated by dots (“.”) and written in the order in which these DimensionComponents are defined^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^29^^>>path:#sdfootnote29sym||name="sdfootnote29anc"]](%%)^^. For example POPULATION.USA would mean that such a VTL Data Set is mapped to the SDMX observations for which the dimension //INDICATOR// is equal to POPULATION and the dimension //COUNTRY// is equal to USA. 391 391 392 392 In the VTL Transformations, this kind of dataset name must be referenced between single quotes because the slash (“/”) is not a regular character according to the VTL rules. 393 393 ... ... @@ -403,7 +403,7 @@ 403 403 404 404 Let us now analyse the different meaning of this kind of mapping in the two mapping directions, i.e. from SDMX to VTL and from VTL to SDMX. 405 405 406 -As already said, the mapping from SDMX to VTL happens when the SDMX dataflows are operand of VTL Transformations, instead the mapping from VTL to SDMX happens when the VTL Data Sets that is result of Transformations {{footnote}}It shouldberemembered that, accordingto theVTL consistencyrules,a givenVTL dataset cannotbe theresultof morethanoneVTL Transformation.{{/footnote}}need to be treated as SDMX objects. This kind of mapping can be applied independently in the two directions and the Dimensions on which the mapping is based can be different in the two directions: these Dimensions are defined in the ToVtlSpaceKey and in the FromVtlSpaceKey classes respectively.425 +As already said, the mapping from SDMX to VTL happens when the SDMX dataflows are operand of VTL Transformations, instead the mapping from VTL to SDMX happens when the VTL Data Sets that is result of Transformations^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^30^^>>path:#sdfootnote30sym||name="sdfootnote30anc"]](%%)^^ need to be treated as SDMX objects. This kind of mapping can be applied independently in the two directions and the Dimensions on which the mapping is based can be different in the two directions: these Dimensions are defined in the ToVtlSpaceKey and in the FromVtlSpaceKey classes respectively. 407 407 408 408 First, let us see what happens in the __mapping direction from SDMX to VTL__, i.e. when parts of a SDMX Dataflow (e.g. DF1(1.0.0)) need to be mapped to distinct VTL Data Sets that are operand of some VTL Transformations. 409 409 ... ... @@ -411,7 +411,7 @@ 411 411 412 412 SDMX Dataflow having INDICATOR=//INDICATORvalue //and COUNTRY=// COUNTRYvalue//. For example, the VTL dataset ‘DF1(1.0.0)/POPULATION.USA’ would contain all the observations of DF1(1.0.0) having INDICATOR = POPULATION and COUNTRY = USA. 413 413 414 -In order to obtain the data structure of these VTL Data Sets from the SDMX one, it is assumed that the SDMX DimensionComponents on which the mapping is based are dropped, i.e. not maintained in the VTL data structure; this is possible because their values are fixed for each one of the invoked VTL Data Sets {{footnote}}Ifthese DimensionComponents would not bedropped, the various VTL Data Sets resultingfrom thiskind of mapping would havenon-matchingvalues for the Identifiers correspondingto themappingDimensions (e.g. POPULATION and COUNTRY). Asaconsequence,takinginto account that the typicalbinaryVTL operations atdatasetlevel(+, -, *, / andso on) are executed on the observationshaving matching values for theidentifiers,it wouldnotbepossible to compose theresultingVTL datasets oneanother(e.g. itwouldnotbepossible to calculatethepopulation ratiobetweenUSAandCANADA).{{/footnote}}. After that, the mapping method from SDMX to VTL specified for the Dataflow DF1(1.0.0) is applied (i.e.433 +In order to obtain the data structure of these VTL Data Sets from the SDMX one, it is assumed that the SDMX DimensionComponents on which the mapping is based are dropped, i.e. not maintained in the VTL data structure; this is possible because their values are fixed for each one of the invoked VTL Data Sets^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^31^^>>path:#sdfootnote31sym||name="sdfootnote31anc"]](%%)^^. After that, the mapping method from SDMX to VTL specified for the Dataflow DF1(1.0.0) is applied (i.e. 415 415 416 416 basic, pivot …). 417 417 ... ... @@ -431,7 +431,7 @@ 431 431 432 432 … … … 433 433 434 -In fact the VTL operator “sub” has exactly the same behaviour. Therefore, mapping different parts of a SDMX Dataflow to different VTL Data Sets in the direction from SDMX to VTL through the ordered concatenation notation is equivalent to a proper use of the operator “**sub**” on such a Dataflow. {{footnote}}Incasetheordered concatenation notation is used,theVTL Transformationdescribedabove, e.g. ‘DF1(1.0)/POPULATION.USA’ := DF1(1.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“USA”],isimplicitlyexecuted. Inorderto test the overallcomplianceoftheVTL programto theVTL consistencyrules,ithas to beconsideredaspartof the VTL program even ifitisnotexplicitlycoded.{{/footnote}}453 +In fact the VTL operator “sub” has exactly the same behaviour. Therefore, mapping different parts of a SDMX Dataflow to different VTL Data Sets in the direction from SDMX to VTL through the ordered concatenation notation is equivalent to a proper use of the operator “**sub**” on such a Dataflow. ^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^32^^>>path:#sdfootnote32sym||name="sdfootnote32anc"]](%%)^^ 435 435 436 436 In the direction from SDMX to VTL it is allowed to omit the value of one or more 437 437 ... ... @@ -459,12 +459,12 @@ 459 459 460 460 Dataflow DF2(1.0.0) having the Dimensions TIME_PERIOD, INDICATOR, 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 and COUNTRY: 461 461 462 -* each part is calculated as a VTL derived Data Set, result of a dedicated VTL Transformation; {{footnote}}Ifthe whole DF2(1.0)iscalculated by meansof just oneVTL Transformation,then themappingbetweentheSDMX Dataflow andthecorrespondingVTL datasetisone-to-oneandthiskind of mapping(oneSDMX Dataflowto manyVTL datasets)doesnotapply.{{/footnote}}463 -* the data structure of all these VTL Data Sets has the TIME_PERIOD identifier and does not have the INDICATOR and COUNTRY identifiers. {{footnote}}Thisis possibleaseachVTL dataset correspondstooneparticularcombinationof valuesof INDICATORandCOUNTRY.{{/footnote}}481 +* each part is calculated as a VTL derived Data Set, result of a dedicated VTL Transformation; ^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^33^^>>path:#sdfootnote33sym||name="sdfootnote33anc"]](%%)^^ 482 +* the data structure of all these VTL Data Sets has the TIME_PERIOD identifier and does not have the INDICATOR and COUNTRY identifiers.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^34^^>>path:#sdfootnote34sym||name="sdfootnote34anc"]](%%)^^ 464 464 465 -Under these hypothesis, such derived VTL Data Sets can be mapped to DF2(1.0.0) by declaring the DimensionComponents INDICATOR and COUNTRY as mapping dimensions {{footnote}}The mappingdimensionsaredefinedasFromVtlSpaceKeysoftheFromVtlSuperSpaceoftheVtlDataflowMappingrelevanttoDF2(1.0).{{/footnote}}.484 +Under these hypothesis, such derived VTL Data Sets can be mapped to DF2(1.0.0) by declaring the DimensionComponents INDICATOR and COUNTRY as mapping dimensions^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^35^^>>path:#sdfootnote35sym||name="sdfootnote35anc"]](%%)^^. 466 466 467 -The corresponding VTL Transformations, assuming that the result needs to be persistent, would be of this kind: {{footnote}}thesymboloftheVTL persistent assignment isused(<-){{/footnote}}486 +The corresponding VTL Transformations, assuming that the result needs to be persistent, would be of this kind:^^ [[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^36^^>>path:#sdfootnote36sym||name="sdfootnote36anc"]](%%)^^ 468 468 469 469 ‘DF2(1.0.0)/INDICATORvalue.COUNTRYvalue’ <- expression 470 470 ... ... @@ -520,9 +520,9 @@ 520 520 521 521 In other words, starting from the datasets explicitly calculated through VTL (in the example ‘DF2(1.0)/GDPPERCAPITA.USA’ and so on), the first step consists in calculating other (non-persistent) VTL datasets (in the example 522 522 523 -DF2bis_GDPPERCAPITA_USA and so on) by adding the identifiers INDICATOR and COUNTRY with the desired values (//INDICATORvalue// and //COUNTRYvalue)//. Finally, all these non-persistent Data Sets are united and give the final result DF2(1.0) {{footnote}}Theresultispersistentin thisexamplebut itcanbealsononpersistentifneeded.{{/footnote}}, which can be mapped one-to-one to the homonymous SDMX Dataflow having the dimension components TIME_PERIOD, INDICATOR and COUNTRY.542 +DF2bis_GDPPERCAPITA_USA and so on) by adding the identifiers INDICATOR and COUNTRY with the desired values (//INDICATORvalue// and //COUNTRYvalue)//. Finally, all these non-persistent Data Sets are united and give the final result DF2(1.0)^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^37^^>>path:#sdfootnote37sym||name="sdfootnote37anc"]](%%)^^, which can be mapped one-to-one to the homonymous SDMX Dataflow having the dimension components TIME_PERIOD, INDICATOR and COUNTRY. 524 524 525 -Therefore, mapping different VTL datasets having the same data structure to different parts of a SDMX Dataflow, i.e. in the direction from VTL to SDMX, through the ordered concatenation notation is equivalent to a proper use of the operators “calc” and “union” on such datasets. {{footnote}}Incasetheordered concatenation notationfrom VTL to SDMXis used,theset of Transformationsdescribedaboveisimplicitlyperformed;therefore,inorder to testtheoverallcomplianceoftheVTL programtotheVTLconsistencyrules,theseimplicitTransformationshaveto beconsideredaspartof theVTL programevenifthey arenotexplicitlycoded.{{/footnote}}544 +Therefore, mapping different VTL datasets having the same data structure to different parts of a SDMX Dataflow, i.e. in the direction from VTL to SDMX, through the ordered concatenation notation is equivalent to a proper use of the operators “calc” and “union” on such datasets. ^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^38^^>>path:#sdfootnote38sym||name="sdfootnote38anc"]](%%)[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^39^^>>path:#sdfootnote39sym||name="sdfootnote39anc"]](%%)^^ 526 526 527 527 It is worth noting that in the direction from VTL to SDMX it is mandatory to specify the value for every Dimension on which the mapping is based (in other word, in the name of the calculated VTL dataset is __not__ possible to omit the value of some of the Dimensions). 528 528 ... ... @@ -530,51 +530,52 @@ 530 530 531 531 With reference to the VTL “model for Variables and Value domains”, the following additional mappings have to be considered: 532 532 533 -(% style="width:1170.29px" %) 534 -|**VTL**|(% style="width:754px" %)**SDMX** 535 -|**Data Set Component**|(% style="width:754px" %)Although this abstraction exists in SDMX, it does not have an explicit definition and correspond to a Component (either a DimensionComponent or a Measure or a DataAttribute) belonging to one specific Dataflow{{footnote}}Through SDMX Constraints, it is possible to specify the values that a Component of a Dataflow can assume.{{/footnote}} 536 -|**Represented Variable**|(% style="width:754px" %)((( 552 +|VTL|SDMX 553 +|**Data Set Component**|Although this abstraction exists in SDMX, it does not have an explicit definition and correspond to a Component (either a DimensionComponent or a Measure or a DataAttribute) belonging to one specific Dataflow^^43^^ 554 +|**Represented Variable**|((( 537 537 **Concept** with a definite 538 538 539 539 Representation 540 540 ))) 541 -|**Value Domain**|( % style="width:754px" %)(((559 +|**Value Domain**|((( 542 542 **Representation** (see the Structure 543 543 544 544 Pattern in the Base Package) 545 545 ))) 546 -|**Enumerated Value Domain / Code List**| (% style="width:754px" %)**Codelist**547 -|**Code**|( % style="width:754px" %)(((564 +|**Enumerated Value Domain / Code List**|**Codelist** 565 +|**Code**|((( 548 548 **Code** (for enumerated 549 549 550 550 DimensionComponent, Measure, DataAttribute) 551 551 ))) 552 -|**Described Value Domain**|( % style="width:754px" %)(((553 -non-enumerated** Representation** 570 +|**Described Value Domain**|((( 571 +non-enumerated** Representation** 554 554 555 555 (having Facets / ExtendedFacets, see the Structure Pattern in the Base Package) 556 556 ))) 557 -|**Value**|(% style="width:754px" %)Although this abstraction exists in SDMX, it does not have an explicit definition and correspond to a **Code** of a Codelist (for enumerated Representations) or 558 -| |(% style="width:754px" %)((( 559 -to a valid **value **(for non-enumerated** **Representations) 575 +|**Value**|Although this abstraction exists in SDMX, it does not have an explicit definition and correspond to a **Code** of a Codelist (for enumerated Representations) or 576 +| |((( 577 +to a valid **value **(for non-enumerated** ** 578 + 579 +Representations) 560 560 ))) 561 -|**Value Domain Subset / Set**| (% style="width:754px" %)This abstraction does not exist in SDMX562 -|**Enumerated Value Domain Subset / Enumerated Set**| (% style="width:754px" %)This abstraction does not exist in SDMX563 -|**Described Value Domain Subset / Described Set**| (% style="width:754px" %)This abstraction does not exist in SDMX564 -|**Set list**| (% style="width:754px" %)This abstraction does not exist in SDMX581 +|**Value Domain Subset / Set**|This abstraction does not exist in SDMX 582 +|**Enumerated Value Domain Subset / Enumerated Set**|This abstraction does not exist in SDMX 583 +|**Described Value Domain Subset / Described Set**|This abstraction does not exist in SDMX 584 +|**Set list**|This abstraction does not exist in SDMX 565 565 566 566 The main difference between VTL and SDMX relies on the fact that the VTL artefacts for defining subsets of Value Domains do not exist in SDMX, therefore the VTL features for referring to predefined subsets are not available in SDMX. These artefacts 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 Component (aimed at defining the set of values that the Component of a Data Set can take, possibly a subset of the codes of Value Domain). 567 567 568 -Another difference consists in the fact that all Value Domains are considered as identifiable objects in VTL either if enumerated or not, while in SDMX the Codelist (corresponding to a VTL enumerated Value Domain) is identifiable, while the SDMX non-enumerated Representation (corresponding to a VTL non-enumerated Value Domain) is not identifiable. As a consequence, the definition of the VTL Rulesets, which in VTL can refer either to enumerated or non-enumerated value domains, in SDMX can refer only to enumerated Value Domains (i.e. to SDMX Codelists). As for the mapping between VTL variables and SDMX Concepts, it should be noted that these artefacts do not coincide perfectly. In fact, the VTL variables are represented variables, defined always on the same Value Domain (“Representation” in SDMX) independently of the data set / data structure in which they appear {{footnote}}Byusing represented variables, VTL canassumethatdatastructures havingthesame variablesasidentifiers canbe composed oneanotherbecausethe correspondentvaluescanmatch.{{/footnote}}, while the SDMX Concepts can have different Representations in different DataStructures.{{footnote}}AConceptbecomesaComponentina DataStructureDefinition,andComponents canhave different LocalRepresentationsin different DataStructureDefinitions,alsooverridingthe(possible)base representationoftheConcept.{{/footnote}}This means that one SDMX Concept can correspond to many VTL Variables, one for each representation the Concept has.588 +Another difference consists in the fact that all Value Domains are considered as identifiable objects in VTL either if enumerated or not, while in SDMX the Codelist (corresponding to a VTL enumerated Value Domain) is identifiable, while the SDMX non-enumerated Representation (corresponding to a VTL non-enumerated Value Domain) is not identifiable. As a consequence, the definition of the VTL Rulesets, which in VTL can refer either to enumerated or non-enumerated value domains, in SDMX can refer only to enumerated Value Domains (i.e. to SDMX Codelists). As for the mapping between VTL variables and SDMX Concepts, it should be noted that these artefacts do not coincide perfectly. In fact, the VTL variables are represented variables, defined always on the same Value Domain (“Representation” in SDMX) independently of the data set / data structure in which they appear^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^40^^>>path:#sdfootnote40sym||name="sdfootnote40anc"]](%%)^^, while the SDMX Concepts can have different Representations in different DataStructures.^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^41^^>>path:#sdfootnote41sym||name="sdfootnote41anc"]](%%)^^ This means that one SDMX Concept can correspond to many VTL Variables, one for each representation the Concept has. 569 569 570 570 Therefore, it is important to be aware that some VTL operations (for example the binary operations at data set level) are consistent only if the components having the same names in the operated VTL Data Sets have also the same representation (i.e. the same Value Domain as for VTL). For example, it is possible to obtain correct results from the VTL expression 571 571 572 -DS_c := DS_a + DS_b (where DS_a, DS_b, DS_c are VTL Data Sets) 592 +DS_c := DS_a + DS_b (where DS_a, DS_b, DS_c are VTL Data Sets) if the matching components in DS_a and DS_b (e.g. ref_date, geo_area, sector …) refer to the same general representation. In simpler words, DS_a and DS_b must use the same values/codes (for ref_date, geo_area, sector … ), otherwise the relevant values would not match and the result of the operation would be wrong. 573 573 574 -if the matching components in DS_a and DS_b (e.g. ref_date, geo_area, sector …) refer to the same general representation. In simpler words, DS_a and DS_b must use the same values/codes (for ref_date, geo_area, sector … ), otherwise the relevant values would not match and the result of the operation would be wrong. 575 - 576 576 As mentioned, the property above is not enforced by construction in SDMX, and different representations of the same Concept can be not compatible one another (for example, it may happen that geo_area is represented by ISO-alpha-3 codes in DS_a and by ISO alpha-2 codes in DS_b). Therefore, it will be up to the definer of VTL 577 577 596 +[[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_59eee18f.gif||alt="Shape5" height="1" width="192"]] 597 + 578 578 Transformations to ensure that the VTL expressions are consistent with the actual representations of the correspondent SDMX Concepts. 579 579 580 580 It remains up to the SDMX-VTL definer also the assurance of the consistency between a VTL Ruleset defined on Variables and the SDMX Components on which the Ruleset is applied. In fact, a VTL Ruleset is expressed by means of the values of the Variables (i.e. SDMX Concepts), i.e. assuming definite representations for them (e.g. ISOalpha-3 for country). If the Ruleset is applied to SDMX Components that have the same name of the Concept they refer to but different representations (e.g. ISO-alpha-2 for country), the Ruleset cannot work properly. ... ... @@ -589,8 +589,7 @@ 589 589 590 590 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_e3df33ae.png||height="543" width="483"]] 591 591 592 -(% class="wikigeneratedid" id="HFigure222013VTLDataTypes" %) 593 -**Figure 22 – VTL Data Types** 612 +==== Figure 22 – VTL Data Types ==== 594 594 595 595 The VTL 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. 596 596 ... ... @@ -597,12 +597,131 @@ 597 597 The VTL basic scalar types are listed below and follow a hierarchical structure in terms of supersets/subsets (e.g. "scalar" is the superset of all the basic scalar types): 598 598 599 599 600 -**Figure 23 – VTL Basic Scalar Types** 601 601 602 602 ((( 603 - 621 +//n// 622 + 623 +//a// 624 + 625 +//e// 626 + 627 +//l// 628 + 629 +//o// 630 + 631 +//o// 632 + 633 +//B// 634 + 635 +//n// 636 + 637 +//o// 638 + 639 +//i// 640 + 641 +//t// 642 + 643 +//a// 644 + 645 +//r// 646 + 647 +//u// 648 + 649 +//D// 650 + 651 +//d// 652 + 653 +//o// 654 + 655 +//i// 656 + 657 +//r// 658 + 659 +//e// 660 + 661 +//p// 662 + 663 +//_// 664 + 665 +//e// 666 + 667 +//m// 668 + 669 +//i// 670 + 671 +//T// 672 + 673 +//e// 674 + 675 +//t// 676 + 677 +//a// 678 + 679 +//D// 680 + 681 +//e// 682 + 683 +//m// 684 + 685 +//i// 686 + 687 +//T// 688 + 689 +//r// 690 + 691 +//e// 692 + 693 +//g// 694 + 695 +//e// 696 + 697 +//t// 698 + 699 +//n// 700 + 701 +//I// 702 + 703 +//r// 704 + 705 +//e// 706 + 707 +//b// 708 + 709 +//m// 710 + 711 +//u// 712 + 713 +//N// 714 + 715 +//g// 716 + 717 +//n// 718 + 719 +//i// 720 + 721 +//r// 722 + 723 +//t// 724 + 725 +//S// 726 + 727 +//r// 728 + 729 +//a// 730 + 731 +//l// 732 + 733 +//a// 734 + 735 +//c// 736 + 737 +//S// 738 + 739 +[[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_82d45833.gif||alt="Shape6" height="231" width="184"]] 604 604 ))) 605 605 742 +==== Figure 23 – VTL Basic Scalar Types ==== 743 + 606 606 === 12.4.2 VTL basic scalar types and SDMX data types === 607 607 608 608 The VTL assumes that a basic scalar type has a unique internal representation and can have more external representations. ... ... @@ -625,159 +625,204 @@ 625 625 626 626 The following table describes the default mapping for converting from the SDMX data types to the VTL basic scalar types. 627 627 628 -(% style="width:823.294px" %) 629 -|(% style="width:509px" %)**SDMX data type (BasicComponentDataType)**|(% style="width:312px" %)**Default VTL basic scalar type** 630 -|(% style="width:509px" %)((( 766 +|SDMX data type (BasicComponentDataType)|Default VTL basic scalar type 767 +|((( 631 631 String 769 + 632 632 (string allowing any character) 633 -)))| (%style="width:312px" %)string634 -|( % style="width:509px" %)(((771 +)))|string 772 +|((( 635 635 Alpha 774 + 636 636 (string which only allows A-z) 637 -)))| (%style="width:312px" %)string638 -|( % style="width:509px" %)(((776 +)))|string 777 +|((( 639 639 AlphaNumeric 779 + 640 640 (string which only allows A-z and 0-9) 641 -)))| (%style="width:312px" %)string642 -|( % style="width:509px" %)(((781 +)))|string 782 +|((( 643 643 Numeric 784 + 644 644 (string which only allows 0-9, but is not numeric so that is can having leading zeros) 645 -)))| (%style="width:312px" %)string646 -|( % style="width:509px" %)(((786 +)))|string 787 +|((( 647 647 BigInteger 789 + 648 648 (corresponds to XML Schema xs:integer datatype; infinite set of integer values) 649 -)))| (% style="width:312px" %)integer650 -|( % style="width:509px" %)(((791 +)))|integer 792 +|((( 651 651 Integer 652 -(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647 (inclusive)) 653 -)))|(% style="width:312px" %)integer 654 -|(% style="width:509px" %)((( 794 + 795 +(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647 796 + 797 +(inclusive)) 798 +)))|integer 799 +|((( 655 655 Long 656 -(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and +9223372036854775807 (inclusive)) 657 -)))|(% style="width:312px" %)integer 658 -|(% style="width:509px" %)((( 801 + 802 +(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and 803 + 804 ++9223372036854775807 (inclusive)) 805 +)))|integer 806 +|((( 659 659 Short 808 + 660 660 (corresponds to XML Schema xs:short datatype; between -32768 and -32767 (inclusive)) 661 -)))| (% style="width:312px" %)integer662 -| (% style="width:509px" %)Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|(% style="width:312px" %)number663 -|( % style="width:509px" %)(((810 +)))|integer 811 +|Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|number 812 +|((( 664 664 Float 814 + 665 665 (corresponds to XML Schema xs:float datatype; patterned after the IEEE single-precision 32-bit floating point type) 666 -)))| (% style="width:312px" %)number667 -|( % style="width:509px" %)(((816 +)))|number 817 +|((( 668 668 Double 819 + 669 669 (corresponds to XML Schema xs:double datatype; patterned after the IEEE double-precision 64-bit floating point type) 670 -)))| (% style="width:312px" %)number671 -|( % style="width:509px" %)(((821 +)))|number 822 +|((( 672 672 Boolean 673 -(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of binary-valued logic: {true, false}) 674 -)))|(% style="width:312px" %)boolean 675 675 676 -(% style="width:822.294px" %) 677 -|(% colspan="2" style="width:507px" %)((( 825 +(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of 826 + 827 +binary-valued logic: {true, false}) 828 +)))|boolean 829 + 830 +| |(% colspan="2" %)((( 678 678 URI 832 + 679 679 (corresponds to the XML Schema xs:anyURI; absolute or relative Uniform Resource Identifier Reference) 680 -)))|(% colspan=" 1"style="width:311px"%)string681 -|(% colspan="2" style="width:507px"%)(((834 +)))|(% colspan="2" %)string 835 +| |(% colspan="2" %)((( 682 682 Count 837 + 683 683 (an integer following a sequential pattern, increasing by 1 for each occurrence) 684 -)))|(% colspan=" 1"style="width:311px"%)integer685 -|(% colspan="2" style="width:507px"%)(((839 +)))|(% colspan="2" %)integer 840 +| |(% colspan="2" %)((( 686 686 InclusiveValueRange 842 + 687 687 (decimal number within a closed interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue) 688 -)))|(% colspan=" 1"style="width:311px"%)number689 -|(% colspan="2" style="width:507px"%)(((844 +)))|(% colspan="2" %)number 845 +| |(% colspan="2" %)((( 690 690 ExclusiveValueRange 847 + 691 691 (decimal number within an open interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue) 692 -)))|(% colspan=" 1"style="width:311px"%)number693 -|(% colspan="2" style="width:507px"%)(((849 +)))|(% colspan="2" %)number 850 +| |(% colspan="2" %)((( 694 694 Incremental 852 + 695 695 (decimal number the increased by a specific interval (defined by the interval facet), which is typically enforced outside of the XML validation) 696 -)))|(% colspan=" 1"style="width:311px"%)number697 -|(% colspan="2" style="width:507px"%)(((854 +)))|(% colspan="2" %)number 855 +| |(% colspan="2" %)((( 698 698 ObservationalTimePeriod 857 + 699 699 (superset of StandardTimePeriod and TimeRange) 700 -)))|(% colspan=" 1"style="width:311px"%)time701 -|(% colspan="2" style="width:507px"%)(((859 +)))|(% colspan="2" %)time 860 +| |(% colspan="2" %)((( 702 702 StandardTimePeriod 703 -(superset of BasicTimePeriod and ReportingTimePeriod) 704 -)))|(% colspan="1" style="width:311px" %)time 705 -|(% colspan="2" style="width:507px" %)((( 862 + 863 +(superset of BasicTimePeriod and 864 + 865 +ReportingTimePeriod) 866 +)))|(% colspan="2" %)time 867 +| |(% colspan="2" %)((( 706 706 BasicTimePeriod 869 + 707 707 (superset of GregorianTimePeriod and DateTime) 708 -)))|(% colspan=" 1"style="width:311px"%)date709 -|(% colspan="2" style="width:507px"%)(((871 +)))|(% colspan="2" %)date 872 +| |(% colspan="2" %)((( 710 710 GregorianTimePeriod 874 + 711 711 (superset of GregorianYear, GregorianYearMonth, and GregorianDay) 712 -)))|(% colspan=" 1"style="width:311px"%)date713 -|(% colspan="2" style="width:507px"%)GregorianYear (YYYY)|(% colspan="1"style="width:311px"%)date714 -|(% colspan="2" style="width:507px"%)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="1"style="width:311px"%)date715 -|(% colspan="2" style="width:507px"%)GregorianDay (YYYY-MM-DD)|(% colspan="1"style="width:311px"%)date716 -|(% colspan="2" style="width:507px"%)(((876 +)))|(% colspan="2" %)date 877 +| |(% colspan="2" %)GregorianYear (YYYY)|(% colspan="2" %)date 878 +| |(% colspan="2" %)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="2" %)date 879 +| |(% colspan="2" %)GregorianDay (YYYY-MM-DD)|(% colspan="2" %)date 880 +| |(% colspan="2" %)((( 717 717 ReportingTimePeriod 718 -(superset of RepostingYear, ReportingSemester, ReportingTrimester, ReportingQuarter, ReportingMonth, ReportingWeek, ReportingDay) 719 -)))|(% colspan="1" style="width:311px" %)time_period 720 -|(% colspan="2" style="width:507px" %)((( 882 + 883 +(superset of RepostingYear, ReportingSemester, 884 + 885 +ReportingTrimester, ReportingQuarter, 886 + 887 +ReportingMonth, ReportingWeek, ReportingDay) 888 +)))|(% colspan="2" %)time_period 889 +| |(% colspan="2" %)((( 721 721 ReportingYear 891 + 722 722 (YYYY-A1 – 1 year period) 723 -)))|(% colspan=" 1"style="width:311px"%)time_period724 -|(% colspan="2" style="width:507px"%)(((893 +)))|(% colspan="2" %)time_period 894 +| |(% colspan="2" %)((( 725 725 ReportingSemester 896 + 726 726 (YYYY-Ss – 6 month period) 727 -)))|(% colspan=" 1"style="width:311px"%)time_period728 -|(% colspan="2" style="width:507px"%)(((898 +)))|(% colspan="2" %)time_period 899 +| |(% colspan="2" %)((( 729 729 ReportingTrimester 901 + 730 730 (YYYY-Tt – 4 month period) 731 -)))|(% colspan=" 1"style="width:311px"%)time_period732 -|(% colspan="2" style="width:507px"%)(((903 +)))|(% colspan="2" %)time_period 904 +| |(% colspan="2" %)((( 733 733 ReportingQuarter 906 + 734 734 (YYYY-Qq – 3 month period) 735 -)))|(% colspan=" 1"style="width:311px"%)time_period736 -|(% colspan="2" style="width:507px"%)(((908 +)))|(% colspan="2" %)time_period 909 +| |(% colspan="2" %)((( 737 737 ReportingMonth 911 + 738 738 (YYYY-Mmm – 1 month period) 739 -)))|(% colspan="1" style="width:311px" %)time_period 740 -|(% colspan="2" style="width:507px" %)ReportingWeek|(% colspan="1" style="width:311px" %)time_period 741 -|(% colspan="1" style="width:507px" %)(YYYY-Www – 7 day period; following ISO 8601 definition of a week in a year)|(% colspan="2" style="width:312px" %) 742 -|(% colspan="1" style="width:507px" %)((( 913 +)))|(% colspan="2" %)time_period 914 +| |(% colspan="2" %)ReportingWeek|(% colspan="2" %)time_period 915 +| |(% colspan="2" %) |(% colspan="2" %) 916 +| |(% colspan="2" %) |(% colspan="2" %) 917 +|(% colspan="2" %)(YYYY-Www – 7 day period; following ISO 8601 definition of a week in a year)|(% colspan="2" %) | 918 +|(% colspan="2" %)((( 743 743 ReportingDay 920 + 744 744 (YYYY-Dddd – 1 day period) 745 -)))|(% colspan="2" style="width:312px"%)time_period746 -|(% colspan=" 1"style="width:507px"%)(((922 +)))|(% colspan="2" %)time_period| 923 +|(% colspan="2" %)((( 747 747 DateTime 925 + 748 748 (YYYY-MM-DDThh:mm:ss) 749 -)))|(% colspan="2" style="width:312px"%)date750 -|(% colspan=" 1"style="width:507px"%)(((927 +)))|(% colspan="2" %)date| 928 +|(% colspan="2" %)((( 751 751 TimeRange 930 + 752 752 (YYYY-MM-DD(Thh:mm:ss)?/<duration>) 753 -)))|(% colspan="2" style="width:312px"%)time754 -|(% colspan=" 1"style="width:507px"%)(((932 +)))|(% colspan="2" %)time| 933 +|(% colspan="2" %)((( 755 755 Month 935 + 756 756 (~-~-MM; speicifies a month independent of a year; e.g. February is black history month in the United States) 757 -)))|(% colspan="2" style="width:312px"%)string758 -|(% colspan=" 1"style="width:507px"%)(((937 +)))|(% colspan="2" %)string| 938 +|(% colspan="2" %)((( 759 759 MonthDay 940 + 760 760 (~-~-MM-DD; specifies a day within a month independent of a year; e.g. Christmas is December 25^^th^^; used to specify reporting year start day) 761 -)))|(% colspan="2" style="width:312px"%)string762 -|(% colspan=" 1"style="width:507px"%)(((942 +)))|(% colspan="2" %)string| 943 +|(% colspan="2" %)((( 763 763 Day 945 + 764 764 (~-~--DD; specifies a day independent of a month or year; e.g. the 15^^th^^ is payday) 765 -)))|(% colspan="2" style="width:312px"%)string766 -|(% colspan=" 1"style="width:507px"%)(((947 +)))|(% colspan="2" %)string| 948 +|(% colspan="2" %)((( 767 767 Time 950 + 768 768 (hh:mm:ss; time independent of a date; e.g. coffee break is at 10:00 AM) 769 -)))|(% colspan="2" style="width:312px"%)string770 -|(% colspan=" 1"style="width:507px"%)(((952 +)))|(% colspan="2" %)string| 953 +|(% colspan="2" %)((( 771 771 Duration 955 + 772 772 (corresponds to XML Schema xs:duration datatype) 773 -)))|(% colspan="2" style="width:312px"%)duration774 -|(% colspan=" 1"style="width:507px"%)XHTML|(% colspan="2"style="width:312px"%)Metadata type – not applicable775 -|(% colspan=" 1"style="width:507px"%)KeyValues|(% colspan="2"style="width:312px"%)Metadata type – not applicable776 -|(% colspan=" 1"style="width:507px"%)IdentifiableReference|(% colspan="2"style="width:312px"%)Metadata type – not applicable777 -|(% colspan=" 1"style="width:507px"%)DataSetReference|(% colspan="2"style="width:312px"%)Metadata type – not applicable957 +)))|(% colspan="2" %)duration| 958 +|(% colspan="2" %)XHTML|(% colspan="2" %)Metadata type – not applicable| 959 +|(% colspan="2" %)KeyValues|(% colspan="2" %)Metadata type – not applicable| 960 +|(% colspan="2" %)IdentifiableReference|(% colspan="2" %)Metadata type – not applicable| 961 +|(% colspan="2" %)DataSetReference|(% colspan="2" %)Metadata type – not applicable| 778 778 779 -(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes" %) 780 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types** 963 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ==== 781 781 782 782 When VTL takes in input SDMX artefacts, it is assumed that a type conversion according to the table above always happens. In case a different VTL basic scalar type is desired, it can be achieved in the VTL program taking in input the default VTL basic scalar type above and applying to it the VTL type conversion features (see the implicit and explicit type conversion and the "cast" operator in the VTL Reference Manual). 783 783 ... ... @@ -785,32 +785,39 @@ 785 785 786 786 The following table describes the default conversion from the VTL basic scalar types to the SDMX data types . 787 787 788 -(% style="width:1073.29px" %) 789 -|(% style="width:207px" %)((( 790 -**VTL basic scalar type** 791 -)))|(% style="width:462px" %)((( 792 -**Default SDMX data type (BasicComponentDataType)** 793 -)))|(% style="width:402px" %)**Default output format** 794 -|(% style="width:207px" %)String|(% style="width:462px" %)String|(% style="width:402px" %)Like XML (xs:string) 795 -|(% style="width:207px" %)Number|(% style="width:462px" %)Float|(% style="width:402px" %)Like XML (xs:float) 796 -|(% style="width:207px" %)Integer|(% style="width:462px" %)Integer|(% style="width:402px" %)Like XML (xs:int) 797 -|(% style="width:207px" %)Date|(% style="width:462px" %)DateTime|(% style="width:402px" %)YYYY-MM-DDT00:00:00Z 798 -|(% style="width:207px" %)Time|(% style="width:462px" %)StandardTimePeriod|(% style="width:402px" %)<date>/<date> (as defined above) 799 -|(% style="width:207px" %)time_period|(% style="width:462px" %)((( 971 +|((( 972 +VTL basic 973 + 974 +scalar type 975 +)))|((( 976 +Default SDMX data type 977 + 978 +(BasicComponentDataType 979 + 980 +) 981 +)))|Default output format 982 +|String|String|Like XML (xs:string) 983 +|Number|Float|Like XML (xs:float) 984 +|Integer|Integer|Like XML (xs:int) 985 +|Date|DateTime|YYYY-MM-DDT00:00:00Z 986 +|Time|StandardTimePeriod|<date>/<date> (as defined above) 987 +|time_period|((( 800 800 ReportingTimePeriod 989 + 801 801 (StandardReportingPeriod) 802 -)))|( % style="width:402px" %)(((991 +)))|((( 803 803 YYYY-Pppp 993 + 804 804 (according to SDMX ) 805 805 ))) 806 -| (% style="width:207px" %)Duration|(% style="width:462px" %)Duration|(% style="width:402px" %)(((996 +|Duration|Duration|((( 807 807 Like XML (xs:duration) 998 + 808 808 PnYnMnDTnHnMnS 809 809 ))) 810 -| (% style="width:207px" %)Boolean|(% style="width:462px" %)Boolean|(% style="width:402px" %)Like XML (xs:boolean) with the values "true" or "false"1001 +|Boolean|Boolean|Like XML (xs:boolean) with the values "true" or "false" 811 811 812 -(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes-1" %) 813 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types** 1003 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ==== 814 814 815 815 In case a different default conversion is desired, it can be achieved through the CustomTypeScheme and CustomType artefacts (see also the section Transformations and Expressions of the SDMX information model). 816 816 ... ... @@ -864,7 +864,7 @@ 864 864 |N|fixed number of digits used in the preceding textual representation of the month or the day 865 865 | | 866 866 867 -The default conversion, either standard or customized, can be used to deduce automatically the representation of the components of the result of a VTL Transformation. In alternative, the representation of the resulting SDMX Dataflow can be given explicitly by providing its DataStructureDefinition. In other words, the representation specified in the DSD, if available, overrides any default conversion {{footnote}}Therepresentationgivenin theDSD shouldobviouslybecompatible withtheVTL data type.{{/footnote}}.1057 +The default conversion, either standard or customized, can be used to deduce automatically the representation of the components of the result of a VTL Transformation. In alternative, the representation of the resulting SDMX Dataflow can be given explicitly by providing its DataStructureDefinition. In other words, the representation specified in the DSD, if available, overrides any default conversion^^[[(% class="wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^42^^>>path:#sdfootnote42sym||name="sdfootnote42anc"]](%%)^^. 868 868 869 869 === 12.4.5 Null Values === 870 870 ... ... @@ -882,8 +882,10 @@ 882 882 883 883 A different format can be specified in the attribute "vtlLiteralFormat" of the CustomType artefact (see also the section Transformations and Expressions of the SDMX information model). 884 884 885 -Like in the case of the conversion of NULLs described in the previous paragraph, the overriding assumption is applied, for a certain VTL basic scalar type, if a value is found for the vtlLiteralFormat attribute of the CustomType of such VTL basic scalar type. The overriding assumption is applied for all the literals of a related VTL TransformationScheme.1075 +Like in the case of the conversion of NULLs described in the previous paragraph, the overriding assumption is applied, for a certain VTL basic scalar type, if a value is found for the vtlLiteralFormat attribute of the CustomType of such VTL basic scalar type. The overriding assumption is applied for all the literals of a related VTL 886 886 1077 +TransformationScheme. 1078 + 887 887 In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats. 888 888 889 889 {{putFootnotes/}}