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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  
... ... @@ -636,204 +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 -|SDMX data type (BasicComponentDataType)|Default VTL basic scalar type
640 -|(((
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 -
643 643  (string allowing any character)
644 -)))|string
645 -|(((
642 +)))|(% style="width:312px" %)string
643 +|(% style="width:509px" %)(((
646 646  Alpha
647 -
648 648  (string which only allows A-z)
649 -)))|string
650 -|(((
646 +)))|(% style="width:312px" %)string
647 +|(% style="width:509px" %)(((
651 651  AlphaNumeric
652 -
653 653  (string which only allows A-z and 0-9)
654 -)))|string
655 -|(((
650 +)))|(% style="width:312px" %)string
651 +|(% style="width:509px" %)(((
656 656  Numeric
657 -
658 658  (string which only allows 0-9, but is not numeric so that is can having leading zeros)
659 -)))|string
660 -|(((
654 +)))|(% style="width:312px" %)string
655 +|(% style="width:509px" %)(((
661 661  BigInteger
662 -
663 663  (corresponds to XML Schema xs:integer datatype; infinite set of integer values)
664 -)))|integer
665 -|(((
658 +)))|(% style="width:312px" %)integer
659 +|(% style="width:509px" %)(((
666 666  Integer
667 -
668 -(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647
669 -
670 -(inclusive))
671 -)))|integer
672 -|(((
661 +(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647 (inclusive))
662 +)))|(% style="width:312px" %)integer
663 +|(% style="width:509px" %)(((
673 673  Long
674 -
675 -(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and
676 -
677 -+9223372036854775807 (inclusive))
678 -)))|integer
679 -|(((
665 +(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and +9223372036854775807 (inclusive))
666 +)))|(% style="width:312px" %)integer
667 +|(% style="width:509px" %)(((
680 680  Short
681 -
682 682  (corresponds to XML Schema xs:short datatype; between -32768 and -32767 (inclusive))
683 -)))|integer
684 -|Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|number
685 -|(((
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" %)(((
686 686  Float
687 -
688 688  (corresponds to XML Schema xs:float datatype; patterned after the IEEE single-precision 32-bit floating point type)
689 -)))|number
690 -|(((
675 +)))|(% style="width:312px" %)number
676 +|(% style="width:509px" %)(((
691 691  Double
692 -
693 693  (corresponds to XML Schema xs:double datatype; patterned after the IEEE double-precision 64-bit floating point type)
694 -)))|number
695 -|(((
679 +)))|(% style="width:312px" %)number
680 +|(% style="width:509px" %)(((
696 696  Boolean
682 +(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of binary-valued logic: {true, false})
683 +)))|(% style="width:312px" %)boolean
697 697  
698 -(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of
699 -
700 -binary-valued logic: {true, false})
701 -)))|boolean
702 -
703 -| |(% colspan="2" %)(((
685 +(% style="width:822.294px" %)
686 +|(% colspan="2" style="width:507px" %)(((
704 704  URI
705 -
706 706  (corresponds to the XML Schema xs:anyURI; absolute or relative Uniform Resource Identifier Reference)
707 -)))|(% colspan="2" %)string
708 -| |(% colspan="2" %)(((
689 +)))|(% colspan="1" style="width:311px" %)string
690 +|(% colspan="2" style="width:507px" %)(((
709 709  Count
710 -
711 711  (an integer following a sequential pattern, increasing by 1 for each occurrence)
712 -)))|(% colspan="2" %)integer
713 -| |(% colspan="2" %)(((
693 +)))|(% colspan="1" style="width:311px" %)integer
694 +|(% colspan="2" style="width:507px" %)(((
714 714  InclusiveValueRange
715 -
716 716  (decimal number within a closed interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
717 -)))|(% colspan="2" %)number
718 -| |(% colspan="2" %)(((
697 +)))|(% colspan="1" style="width:311px" %)number
698 +|(% colspan="2" style="width:507px" %)(((
719 719  ExclusiveValueRange
720 -
721 721  (decimal number within an open interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
722 -)))|(% colspan="2" %)number
723 -| |(% colspan="2" %)(((
701 +)))|(% colspan="1" style="width:311px" %)number
702 +|(% colspan="2" style="width:507px" %)(((
724 724  Incremental
725 -
726 726  (decimal number the increased by a specific interval (defined by the interval facet), which is typically enforced outside of the XML validation)
727 -)))|(% colspan="2" %)number
728 -| |(% colspan="2" %)(((
705 +)))|(% colspan="1" style="width:311px" %)number
706 +|(% colspan="2" style="width:507px" %)(((
729 729  ObservationalTimePeriod
730 -
731 731  (superset of StandardTimePeriod and TimeRange)
732 -)))|(% colspan="2" %)time
733 -| |(% colspan="2" %)(((
709 +)))|(% colspan="1" style="width:311px" %)time
710 +|(% colspan="2" style="width:507px" %)(((
734 734  StandardTimePeriod
735 -
736 -(superset of BasicTimePeriod and
737 -
738 -ReportingTimePeriod)
739 -)))|(% colspan="2" %)time
740 -| |(% colspan="2" %)(((
712 +(superset of BasicTimePeriod and ReportingTimePeriod)
713 +)))|(% colspan="1" style="width:311px" %)time
714 +|(% colspan="2" style="width:507px" %)(((
741 741  BasicTimePeriod
742 -
743 743  (superset of GregorianTimePeriod and DateTime)
744 -)))|(% colspan="2" %)date
745 -| |(% colspan="2" %)(((
717 +)))|(% colspan="1" style="width:311px" %)date
718 +|(% colspan="2" style="width:507px" %)(((
746 746  GregorianTimePeriod
747 -
748 748  (superset of GregorianYear, GregorianYearMonth, and GregorianDay)
749 -)))|(% colspan="2" %)date
750 -| |(% colspan="2" %)GregorianYear (YYYY)|(% colspan="2" %)date
751 -| |(% colspan="2" %)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="2" %)date
752 -| |(% colspan="2" %)GregorianDay (YYYY-MM-DD)|(% colspan="2" %)date
753 -| |(% 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" %)(((
754 754  ReportingTimePeriod
755 -
756 -(superset of RepostingYear, ReportingSemester,
757 -
758 -ReportingTrimester, ReportingQuarter,
759 -
760 -ReportingMonth, ReportingWeek, ReportingDay)
761 -)))|(% colspan="2" %)time_period
762 -| |(% 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" %)(((
763 763  ReportingYear
764 -
765 765  (YYYY-A1 – 1 year period)
766 -)))|(% colspan="2" %)time_period
767 -| |(% colspan="2" %)(((
732 +)))|(% colspan="1" style="width:311px" %)time_period
733 +|(% colspan="2" style="width:507px" %)(((
768 768  ReportingSemester
769 -
770 770  (YYYY-Ss – 6 month period)
771 -)))|(% colspan="2" %)time_period
772 -| |(% colspan="2" %)(((
736 +)))|(% colspan="1" style="width:311px" %)time_period
737 +|(% colspan="2" style="width:507px" %)(((
773 773  ReportingTrimester
774 -
775 775  (YYYY-Tt – 4 month period)
776 -)))|(% colspan="2" %)time_period
777 -| |(% colspan="2" %)(((
740 +)))|(% colspan="1" style="width:311px" %)time_period
741 +|(% colspan="2" style="width:507px" %)(((
778 778  ReportingQuarter
779 -
780 780  (YYYY-Qq – 3 month period)
781 -)))|(% colspan="2" %)time_period
782 -| |(% colspan="2" %)(((
744 +)))|(% colspan="1" style="width:311px" %)time_period
745 +|(% colspan="2" style="width:507px" %)(((
783 783  ReportingMonth
784 -
785 785  (YYYY-Mmm – 1 month period)
786 -)))|(% colspan="2" %)time_period
787 -| |(% colspan="2" %)ReportingWeek|(% colspan="2" %)time_period
788 -| |(% colspan="2" %) |(% colspan="2" %)
789 -| |(% colspan="2" %) |(% colspan="2" %)
790 -|(% colspan="2" %)(YYYY-Www – 7 day period; following ISO 8601 definition of a week in a year)|(% colspan="2" %) |
791 -|(% 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" %)(((
792 792  ReportingDay
793 -
794 794  (YYYY-Dddd – 1 day period)
795 -)))|(% colspan="2" %)time_period|
796 -|(% colspan="2" %)(((
754 +)))|(% colspan="2" style="width:312px" %)time_period
755 +|(% colspan="1" style="width:507px" %)(((
797 797  DateTime
798 -
799 799  (YYYY-MM-DDThh:mm:ss)
800 -)))|(% colspan="2" %)date|
801 -|(% colspan="2" %)(((
758 +)))|(% colspan="2" style="width:312px" %)date
759 +|(% colspan="1" style="width:507px" %)(((
802 802  TimeRange
803 -
804 804  (YYYY-MM-DD(Thh:mm:ss)?/<duration>)
805 -)))|(% colspan="2" %)time|
806 -|(% colspan="2" %)(((
762 +)))|(% colspan="2" style="width:312px" %)time
763 +|(% colspan="1" style="width:507px" %)(((
807 807  Month
808 -
809 809  (~-~-MM; speicifies a month independent of a year; e.g. February is black history month in the United States)
810 -)))|(% colspan="2" %)string|
811 -|(% colspan="2" %)(((
766 +)))|(% colspan="2" style="width:312px" %)string
767 +|(% colspan="1" style="width:507px" %)(((
812 812  MonthDay
813 -
814 814  (~-~-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)
815 -)))|(% colspan="2" %)string|
816 -|(% colspan="2" %)(((
770 +)))|(% colspan="2" style="width:312px" %)string
771 +|(% colspan="1" style="width:507px" %)(((
817 817  Day
818 -
819 819  (~-~--DD; specifies a day independent of a month or year; e.g. the 15^^th^^ is payday)
820 -)))|(% colspan="2" %)string|
821 -|(% colspan="2" %)(((
774 +)))|(% colspan="2" style="width:312px" %)string
775 +|(% colspan="1" style="width:507px" %)(((
822 822  Time
823 -
824 824  (hh:mm:ss; time independent of a date; e.g. coffee break is at 10:00 AM)
825 -)))|(% colspan="2" %)string|
826 -|(% colspan="2" %)(((
778 +)))|(% colspan="2" style="width:312px" %)string
779 +|(% colspan="1" style="width:507px" %)(((
827 827  Duration
828 -
829 829  (corresponds to XML Schema xs:duration datatype)
830 -)))|(% colspan="2" %)duration|
831 -|(% colspan="2" %)XHTML|(% colspan="2" %)Metadata type – not applicable|
832 -|(% colspan="2" %)KeyValues|(% colspan="2" %)Metadata type – not applicable|
833 -|(% colspan="2" %)IdentifiableReference|(% colspan="2" %)Metadata type – not applicable|
834 -|(% 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
835 835  
836 -==== 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**
837 837  
838 838  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).
839 839  
... ... @@ -841,39 +841,32 @@
841 841  
842 842  The following table describes the default conversion from the VTL basic scalar types to the SDMX data types .
843 843  
844 -|(((
845 -VTL basic
846 -
847 -scalar type
848 -)))|(((
849 -Default SDMX data type
850 -
851 -(BasicComponentDataType
852 -
853 -)
854 -)))|Default output format
855 -|String|String|Like XML (xs:string)
856 -|Number|Float|Like XML (xs:float)
857 -|Integer|Integer|Like XML (xs:int)
858 -|Date|DateTime|YYYY-MM-DDT00:00:00Z
859 -|Time|StandardTimePeriod|<date>/<date> (as defined above)
860 -|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" %)(((
861 861  ReportingTimePeriod
862 -
863 863  (StandardReportingPeriod)
864 -)))|(((
811 +)))|(% style="width:402px" %)(((
865 865  YYYY-Pppp
866 -
867 867  (according to SDMX )
868 868  )))
869 -|Duration|Duration|(((
815 +|(% style="width:207px" %)Duration|(% style="width:462px" %)Duration|(% style="width:402px" %)(((
870 870  Like XML (xs:duration)
871 -
872 872  PnYnMnDTnHnMnS
873 873  )))
874 -|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"
875 875  
876 -==== 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**
877 877  
878 878  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).
879 879  
... ... @@ -927,7 +927,7 @@
927 927  |N|fixed number of digits used in the preceding textual representation of the month or the day
928 928  | |
929 929  
930 -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}}.
931 931  
932 932  === 12.4.5 Null Values ===
933 933  
... ... @@ -945,10 +945,8 @@
945 945  
946 946  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).
947 947  
948 -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.
949 949  
950 -TransformationScheme.
951 -
952 952  In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats.
953 953  
954 954  {{putFootnotes/}}