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

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... ... @@ -730,27 +730,20 @@
730 730  |IdentifiableReference|Metadata type – not applicable
731 731  |DataSetReference|Metadata type – not applicable
732 732  
733 -додол
733 +**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
734 734  
735 -==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
736 -
737 737  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).
738 738  
739 -1.
740 -11.
741 -111. Mapping VTL basic scalar types to SDMX data types
737 +=== 12.4.4 Mapping VTL basic scalar types to SDMX data types ===
742 742  
743 743  The following table describes the default conversion from the VTL basic scalar types to the SDMX data types .
744 744  
745 745  |(((
746 746  VTL basic
747 -
748 748  scalar type
749 749  )))|(((
750 750  Default SDMX data type
751 -
752 752  (BasicComponentDataType
753 -
754 754  )
755 755  )))|Default output format
756 756  |String|String|Like XML (xs:string)
... ... @@ -760,17 +760,15 @@
760 760  |Time|StandardTimePeriod|<date>/<date> (as defined above)
761 761  |time_period|(((
762 762  ReportingTimePeriod
763 -
764 764  (StandardReportingPeriod)
765 765  )))|(((
766 766   YYYY-Pppp
767 -
768 768  (according to SDMX )
769 769  )))
770 770  |Duration|Duration|Like XML (xs:duration) PnYnMnDTnHnMnS
771 771  |Boolean|Boolean|Like XML (xs:boolean) with the values "true" or "false"
772 772  
773 -==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
764 +**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
774 774  
775 775  In case a different default conversion is desired, it can be achieved through the CustomTypeScheme and CustomType artefacts (see also the section
776 776  
... ... @@ -828,17 +828,13 @@
828 828  
829 829  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}}.
830 830  
831 -1.
832 -11.
833 -111. Null Values
822 +=== 12.4.3 Null Values ===
834 834  
835 835  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.
836 836  
837 837  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.
838 838  
839 -1.
840 -11.
841 -111. Format of the literals used in VTL Transformations
828 +=== 12.4.5 Format of the literals used in VTL Transformations ===
842 842  
843 843  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.
844 844  
... ... @@ -852,7 +852,6 @@
852 852  
853 853  In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats.
854 854  
855 -
856 856  ----
857 857  
858 858  {{putFootnotes/}}