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Last modified by Artur on 2025/09/10 11:19
From version 1.14
edited by Helena
on 2025/06/16 13:14
Change comment: There is no comment for this version
To version 1.13
edited by Helena
on 2025/06/16 13:13
Change comment: There is no comment for this version

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730 730  |IdentifiableReference|Metadata type – not applicable
731 731  |DataSetReference|Metadata type – not applicable
732 732  
733 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
733 +додол
734 734  
735 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
736 +
735 735  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).
736 736  
737 -=== 12.4.4 Mapping VTL basic scalar types to SDMX data types ===
739 +1.
740 +11.
741 +111. Mapping VTL basic scalar types to SDMX data types
738 738  
739 739  The following table describes the default conversion from the VTL basic scalar types to the SDMX data types .
740 740  
741 741  |(((
742 742  VTL basic
747 +
743 743  scalar type
744 744  )))|(((
745 745  Default SDMX data type
751 +
746 746  (BasicComponentDataType
753 +
747 747  )
748 748  )))|Default output format
749 749  |String|String|Like XML (xs:string)
... ... @@ -753,15 +753,17 @@
753 753  |Time|StandardTimePeriod|<date>/<date> (as defined above)
754 754  |time_period|(((
755 755  ReportingTimePeriod
763 +
756 756  (StandardReportingPeriod)
757 757  )))|(((
758 758   YYYY-Pppp
767 +
759 759  (according to SDMX )
760 760  )))
761 761  |Duration|Duration|Like XML (xs:duration) PnYnMnDTnHnMnS
762 762  |Boolean|Boolean|Like XML (xs:boolean) with the values "true" or "false"
763 763  
764 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
773 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
765 765  
766 766  In case a different default conversion is desired, it can be achieved through the CustomTypeScheme and CustomType artefacts (see also the section
767 767  
... ... @@ -819,13 +819,17 @@
819 819  
820 820  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}}The representation given in the DSD should obviously be compatible with the VTL data type.{{/footnote}}.
821 821  
822 -=== 12.4.3 Null Values ===
831 +1.
832 +11.
833 +111. Null Values
823 823  
824 824  In the conversions from SDMX to VTL it is assumed by default that a missing value in SDMX becomes a NULL in VTL. After the conversion, the NULLs can be manipulated through the proper VTL operators.
825 825  
826 826  On the other side, the VTL programs can produce in output NULL values for Measures and Attributes (Null values are not allowed in the Identifiers). In the conversion from VTL to SDMX, it is assumed that a NULL in VTL becomes a missing value in SDMX. In the conversion from VTL to SDMX, the default assumption can be overridden, separately for each VTL basic scalar type, by specifying which the value that represents the NULL in SDMX is. This can be specified in the attribute "nullValue" of the CustomType artefact (see also the section Transformations and Expressions of the SDMX information model). A CustomType belongs to a CustomTypeScheme, which can be referenced by one or more TransformationScheme (i.e. VTL programs). The overriding assumption is applied for all the SDMX Dataflows calculated in the TransformationScheme.
827 827  
828 -=== 12.4.5 Format of the literals used in VTL Transformations ===
839 +1.
840 +11.
841 +111. Format of the literals used in VTL Transformations
829 829  
830 830  The VTL programs can contain literals, i.e. specific values of certain data types written directly in the VTL definitions or expressions. The VTL does not prescribe a specific format for the literals and leave the specific VTL systems and the definers of VTL Transformations free of using their preferred formats.
831 831  
... ... @@ -839,6 +839,7 @@
839 839  
840 840  In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats.
841 841  
855 +
842 842  ----
843 843  
844 844  {{putFootnotes/}}