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... ... @@ -14,10 +14,8 @@
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
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.
18 18  
19 -Transformation (nameable artefact). Each Transformation assigns the outcome of the evaluation of a VTL expression to a result.
20 -
21 21  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.
22 22  
23 23  == 12.2 References to SDMX artefacts from VTL statements ==
... ... @@ -243,7 +243,7 @@
243 243  
244 244  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;
245 245  
246 -*
244 +*
247 247  ** 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).
248 248  ** 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.
249 249  
... ... @@ -636,189 +636,159 @@
636 636  
637 637  The following table describes the default mapping for converting from the SDMX data types to the VTL basic scalar types.
638 638  
639 -|(% style="width:501px" %)SDMX data type (BasicComponentDataType)|(% style="width:1437px" %)Default VTL basic scalar type
640 -|(% style="width:501px" %)(((
637 +(% style="width:823.294px" %)
638 +|(% style="width:509px" %)**SDMX data type (BasicComponentDataType)**|(% style="width:312px" %)**Default VTL basic scalar type**
639 +|(% style="width:509px" %)(((
641 641  String
642 642  (string allowing any character)
643 -)))|(% style="width:1437px" %)string
644 -|(% style="width:501px" %)(((
642 +)))|(% style="width:312px" %)string
643 +|(% style="width:509px" %)(((
645 645  Alpha
646 646  (string which only allows A-z)
647 -)))|(% style="width:1437px" %)string
648 -|(% style="width:501px" %)(((
646 +)))|(% style="width:312px" %)string
647 +|(% style="width:509px" %)(((
649 649  AlphaNumeric
650 650  (string which only allows A-z and 0-9)
651 -)))|(% style="width:1437px" %)string
652 -|(% style="width:501px" %)(((
650 +)))|(% style="width:312px" %)string
651 +|(% style="width:509px" %)(((
653 653  Numeric
654 654  (string which only allows 0-9, but is not numeric so that is can having leading zeros)
655 -)))|(% style="width:1437px" %)string
656 -|(% style="width:501px" %)(((
654 +)))|(% style="width:312px" %)string
655 +|(% style="width:509px" %)(((
657 657  BigInteger
658 658  (corresponds to XML Schema xs:integer datatype; infinite set of integer values)
659 -)))|(% style="width:1437px" %)integer
660 -|(% style="width:501px" %)(((
658 +)))|(% style="width:312px" %)integer
659 +|(% style="width:509px" %)(((
661 661  Integer
662 662  (corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647 (inclusive))
663 -)))|(% style="width:1437px" %)integer
664 -|(% style="width:501px" %)(((
662 +)))|(% style="width:312px" %)integer
663 +|(% style="width:509px" %)(((
665 665  Long
666 -(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and
667 -
668 -+9223372036854775807 (inclusive))
669 -)))|(% style="width:1437px" %)integer
670 -|(% style="width:501px" %)(((
665 +(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and +9223372036854775807 (inclusive))
666 +)))|(% style="width:312px" %)integer
667 +|(% style="width:509px" %)(((
671 671  Short
672 672  (corresponds to XML Schema xs:short datatype; between -32768 and -32767 (inclusive))
673 -)))|(% style="width:1437px" %)integer
674 -|(% style="width:501px" %)Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|(% style="width:1437px" %)number
675 -|(% style="width:501px" %)(((
670 +)))|(% style="width:312px" %)integer
671 +|(% style="width:509px" %)Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|(% style="width:312px" %)number
672 +|(% style="width:509px" %)(((
676 676  Float
677 677  (corresponds to XML Schema xs:float datatype; patterned after the IEEE single-precision 32-bit floating point type)
678 -)))|(% style="width:1437px" %)number
679 -|(% style="width:501px" %)(((
675 +)))|(% style="width:312px" %)number
676 +|(% style="width:509px" %)(((
680 680  Double
681 681  (corresponds to XML Schema xs:double datatype; patterned after the IEEE double-precision 64-bit floating point type)
682 -)))|(% style="width:1437px" %)number
683 -|(% style="width:501px" %)(((
679 +)))|(% style="width:312px" %)number
680 +|(% style="width:509px" %)(((
684 684  Boolean
685 685  (corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of binary-valued logic: {true, false})
686 -)))|(% style="width:1437px" %)boolean
683 +)))|(% style="width:312px" %)boolean
687 687  
688 -| |(% colspan="2" %)(((
685 +(% style="width:822.294px" %)
686 +|(% colspan="2" style="width:507px" %)(((
689 689  URI
690 -
691 691  (corresponds to the XML Schema xs:anyURI; absolute or relative Uniform Resource Identifier Reference)
692 -)))|(% colspan="2" %)string
693 -| |(% colspan="2" %)(((
689 +)))|(% colspan="1" style="width:311px" %)string
690 +|(% colspan="2" style="width:507px" %)(((
694 694  Count
695 -
696 696  (an integer following a sequential pattern, increasing by 1 for each occurrence)
697 -)))|(% colspan="2" %)integer
698 -| |(% colspan="2" %)(((
693 +)))|(% colspan="1" style="width:311px" %)integer
694 +|(% colspan="2" style="width:507px" %)(((
699 699  InclusiveValueRange
700 -
701 701  (decimal number within a closed interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
702 -)))|(% colspan="2" %)number
703 -| |(% colspan="2" %)(((
697 +)))|(% colspan="1" style="width:311px" %)number
698 +|(% colspan="2" style="width:507px" %)(((
704 704  ExclusiveValueRange
705 -
706 706  (decimal number within an open interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
707 -)))|(% colspan="2" %)number
708 -| |(% colspan="2" %)(((
701 +)))|(% colspan="1" style="width:311px" %)number
702 +|(% colspan="2" style="width:507px" %)(((
709 709  Incremental
710 -
711 711  (decimal number the increased by a specific interval (defined by the interval facet), which is typically enforced outside of the XML validation)
712 -)))|(% colspan="2" %)number
713 -| |(% colspan="2" %)(((
705 +)))|(% colspan="1" style="width:311px" %)number
706 +|(% colspan="2" style="width:507px" %)(((
714 714  ObservationalTimePeriod
715 -
716 716  (superset of StandardTimePeriod and TimeRange)
717 -)))|(% colspan="2" %)time
718 -| |(% colspan="2" %)(((
709 +)))|(% colspan="1" style="width:311px" %)time
710 +|(% colspan="2" style="width:507px" %)(((
719 719  StandardTimePeriod
720 -
721 -(superset of BasicTimePeriod and
722 -
723 -ReportingTimePeriod)
724 -)))|(% colspan="2" %)time
725 -| |(% colspan="2" %)(((
712 +(superset of BasicTimePeriod and ReportingTimePeriod)
713 +)))|(% colspan="1" style="width:311px" %)time
714 +|(% colspan="2" style="width:507px" %)(((
726 726  BasicTimePeriod
727 -
728 728  (superset of GregorianTimePeriod and DateTime)
729 -)))|(% colspan="2" %)date
730 -| |(% colspan="2" %)(((
717 +)))|(% colspan="1" style="width:311px" %)date
718 +|(% colspan="2" style="width:507px" %)(((
731 731  GregorianTimePeriod
732 -
733 733  (superset of GregorianYear, GregorianYearMonth, and GregorianDay)
734 -)))|(% colspan="2" %)date
735 -| |(% colspan="2" %)GregorianYear (YYYY)|(% colspan="2" %)date
736 -| |(% colspan="2" %)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="2" %)date
737 -| |(% colspan="2" %)GregorianDay (YYYY-MM-DD)|(% colspan="2" %)date
738 -| |(% colspan="2" %)(((
721 +)))|(% colspan="1" style="width:311px" %)date
722 +|(% colspan="2" style="width:507px" %)GregorianYear (YYYY)|(% colspan="1" style="width:311px" %)date
723 +|(% colspan="2" style="width:507px" %)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="1" style="width:311px" %)date
724 +|(% colspan="2" style="width:507px" %)GregorianDay (YYYY-MM-DD)|(% colspan="1" style="width:311px" %)date
725 +|(% colspan="2" style="width:507px" %)(((
739 739  ReportingTimePeriod
740 -
741 -(superset of RepostingYear, ReportingSemester,
742 -
743 -ReportingTrimester, ReportingQuarter,
744 -
745 -ReportingMonth, ReportingWeek, ReportingDay)
746 -)))|(% colspan="2" %)time_period
747 -| |(% colspan="2" %)(((
727 +(superset of RepostingYear, ReportingSemester, ReportingTrimester, ReportingQuarter, ReportingMonth, ReportingWeek, ReportingDay)
728 +)))|(% colspan="1" style="width:311px" %)time_period
729 +|(% colspan="2" style="width:507px" %)(((
748 748  ReportingYear
749 -
750 750  (YYYY-A1 – 1 year period)
751 -)))|(% colspan="2" %)time_period
752 -| |(% colspan="2" %)(((
732 +)))|(% colspan="1" style="width:311px" %)time_period
733 +|(% colspan="2" style="width:507px" %)(((
753 753  ReportingSemester
754 -
755 755  (YYYY-Ss – 6 month period)
756 -)))|(% colspan="2" %)time_period
757 -| |(% colspan="2" %)(((
736 +)))|(% colspan="1" style="width:311px" %)time_period
737 +|(% colspan="2" style="width:507px" %)(((
758 758  ReportingTrimester
759 -
760 760  (YYYY-Tt – 4 month period)
761 -)))|(% colspan="2" %)time_period
762 -| |(% colspan="2" %)(((
740 +)))|(% colspan="1" style="width:311px" %)time_period
741 +|(% colspan="2" style="width:507px" %)(((
763 763  ReportingQuarter
764 -
765 765  (YYYY-Qq – 3 month period)
766 -)))|(% colspan="2" %)time_period
767 -| |(% colspan="2" %)(((
744 +)))|(% colspan="1" style="width:311px" %)time_period
745 +|(% colspan="2" style="width:507px" %)(((
768 768  ReportingMonth
769 -
770 770  (YYYY-Mmm – 1 month period)
771 -)))|(% colspan="2" %)time_period
772 -| |(% colspan="2" %)ReportingWeek|(% colspan="2" %)time_period
773 -| |(% colspan="2" %) |(% colspan="2" %)
774 -| |(% colspan="2" %) |(% colspan="2" %)
775 -|(% colspan="2" %)(YYYY-Www – 7 day period; following ISO 8601 definition of a week in a year)|(% colspan="2" %) |
776 -|(% colspan="2" %)(((
748 +)))|(% colspan="1" style="width:311px" %)time_period
749 +|(% colspan="2" style="width:507px" %)ReportingWeek|(% colspan="1" style="width:311px" %)time_period
750 +|(% 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" %)
751 +|(% colspan="1" style="width:507px" %)(((
777 777  ReportingDay
778 -
779 779  (YYYY-Dddd – 1 day period)
780 -)))|(% colspan="2" %)time_period|
781 -|(% colspan="2" %)(((
754 +)))|(% colspan="2" style="width:312px" %)time_period
755 +|(% colspan="1" style="width:507px" %)(((
782 782  DateTime
783 -
784 784  (YYYY-MM-DDThh:mm:ss)
785 -)))|(% colspan="2" %)date|
786 -|(% colspan="2" %)(((
758 +)))|(% colspan="2" style="width:312px" %)date
759 +|(% colspan="1" style="width:507px" %)(((
787 787  TimeRange
788 -
789 789  (YYYY-MM-DD(Thh:mm:ss)?/<duration>)
790 -)))|(% colspan="2" %)time|
791 -|(% colspan="2" %)(((
762 +)))|(% colspan="2" style="width:312px" %)time
763 +|(% colspan="1" style="width:507px" %)(((
792 792  Month
793 -
794 794  (~-~-MM; speicifies a month independent of a year; e.g. February is black history month in the United States)
795 -)))|(% colspan="2" %)string|
796 -|(% colspan="2" %)(((
766 +)))|(% colspan="2" style="width:312px" %)string
767 +|(% colspan="1" style="width:507px" %)(((
797 797  MonthDay
798 -
799 799  (~-~-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)
800 -)))|(% colspan="2" %)string|
801 -|(% colspan="2" %)(((
770 +)))|(% colspan="2" style="width:312px" %)string
771 +|(% colspan="1" style="width:507px" %)(((
802 802  Day
803 -
804 804  (~-~--DD; specifies a day independent of a month or year; e.g. the 15^^th^^ is payday)
805 -)))|(% colspan="2" %)string|
806 -|(% colspan="2" %)(((
774 +)))|(% colspan="2" style="width:312px" %)string
775 +|(% colspan="1" style="width:507px" %)(((
807 807  Time
808 -
809 809  (hh:mm:ss; time independent of a date; e.g. coffee break is at 10:00 AM)
810 -)))|(% colspan="2" %)string|
811 -|(% colspan="2" %)(((
778 +)))|(% colspan="2" style="width:312px" %)string
779 +|(% colspan="1" style="width:507px" %)(((
812 812  Duration
813 -
814 814  (corresponds to XML Schema xs:duration datatype)
815 -)))|(% colspan="2" %)duration|
816 -|(% colspan="2" %)XHTML|(% colspan="2" %)Metadata type – not applicable|
817 -|(% colspan="2" %)KeyValues|(% colspan="2" %)Metadata type – not applicable|
818 -|(% colspan="2" %)IdentifiableReference|(% colspan="2" %)Metadata type – not applicable|
819 -|(% colspan="2" %)DataSetReference|(% colspan="2" %)Metadata type – not applicable|
782 +)))|(% colspan="2" style="width:312px" %)duration
783 +|(% colspan="1" style="width:507px" %)XHTML|(% colspan="2" style="width:312px" %)Metadata type – not applicable
784 +|(% colspan="1" style="width:507px" %)KeyValues|(% colspan="2" style="width:312px" %)Metadata type – not applicable
785 +|(% colspan="1" style="width:507px" %)IdentifiableReference|(% colspan="2" style="width:312px" %)Metadata type – not applicable
786 +|(% colspan="1" style="width:507px" %)DataSetReference|(% colspan="2" style="width:312px" %)Metadata type – not applicable
820 820  
821 -==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
788 +(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes" %)
789 +**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
822 822  
823 823  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).
824 824  
... ... @@ -826,39 +826,32 @@
826 826  
827 827  The following table describes the default conversion from the VTL basic scalar types to the SDMX data types .
828 828  
829 -|(((
830 -VTL basic
831 -
832 -scalar type
833 -)))|(((
834 -Default SDMX data type
835 -
836 -(BasicComponentDataType
837 -
838 -)
839 -)))|Default output format
840 -|String|String|Like XML (xs:string)
841 -|Number|Float|Like XML (xs:float)
842 -|Integer|Integer|Like XML (xs:int)
843 -|Date|DateTime|YYYY-MM-DDT00:00:00Z
844 -|Time|StandardTimePeriod|<date>/<date> (as defined above)
845 -|time_period|(((
797 +(% style="width:1073.29px" %)
798 +|(% style="width:207px" %)(((
799 +**VTL basic scalar type**
800 +)))|(% style="width:462px" %)(((
801 +**Default SDMX data type (BasicComponentDataType)**
802 +)))|(% style="width:402px" %)**Default output format**
803 +|(% style="width:207px" %)String|(% style="width:462px" %)String|(% style="width:402px" %)Like XML (xs:string)
804 +|(% style="width:207px" %)Number|(% style="width:462px" %)Float|(% style="width:402px" %)Like XML (xs:float)
805 +|(% style="width:207px" %)Integer|(% style="width:462px" %)Integer|(% style="width:402px" %)Like XML (xs:int)
806 +|(% style="width:207px" %)Date|(% style="width:462px" %)DateTime|(% style="width:402px" %)YYYY-MM-DDT00:00:00Z
807 +|(% style="width:207px" %)Time|(% style="width:462px" %)StandardTimePeriod|(% style="width:402px" %)<date>/<date> (as defined above)
808 +|(% style="width:207px" %)time_period|(% style="width:462px" %)(((
846 846  ReportingTimePeriod
847 -
848 848  (StandardReportingPeriod)
849 -)))|(((
811 +)))|(% style="width:402px" %)(((
850 850  YYYY-Pppp
851 -
852 852  (according to SDMX )
853 853  )))
854 -|Duration|Duration|(((
815 +|(% style="width:207px" %)Duration|(% style="width:462px" %)Duration|(% style="width:402px" %)(((
855 855  Like XML (xs:duration)
856 -
857 857  PnYnMnDTnHnMnS
858 858  )))
859 -|Boolean|Boolean|Like XML (xs:boolean) with the values "true" or "false"
819 +|(% style="width:207px" %)Boolean|(% style="width:462px" %)Boolean|(% style="width:402px" %)Like XML (xs:boolean) with the values "true" or "false"
860 860  
861 -==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
821 +(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes-1" %)
822 +**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
862 862  
863 863  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).
864 864  
... ... @@ -912,7 +912,7 @@
912 912  |N|fixed number of digits used in the preceding textual representation of the month or the day
913 913  | |
914 914  
915 -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 wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink wikiinternallink" %)^^42^^>>path:#sdfootnote42sym||name="sdfootnote42anc"]](%%)^^.
876 +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}}.
916 916  
917 917  === 12.4.5 Null Values ===
918 918  
... ... @@ -930,10 +930,8 @@
930 930  
931 931  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).
932 932  
933 -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
894 +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.
934 934  
935 -TransformationScheme.
936 -
937 937  In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats.
938 938  
939 939  {{putFootnotes/}}