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edited by Helena
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edited by Helena
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... ... @@ -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.
... ... @@ -198,7 +198,7 @@
198 198  
199 199  === 12.3.3 Mapping from SDMX to VTL data structures ===
200 200  
201 -==== 12.3.3.1 Basic Mapping ====
205 +**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  
... ... @@ -228,11 +228,18 @@
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;
235 +* 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
236 +
237 +Component;
238 +
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;
242 +** 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
243 +
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 +
246 +*
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  
... ... @@ -255,7 +255,10 @@
255 255  At observation / data point level, calling Cj (j=1, … n) the j^^th^^ Code of the MeasureDimension:
256 256  
257 257  * The set of SDMX observations having the same values for all the Dimensions except than the MeasureDimension become one multi-measure VTL Data Point, having one Measure for each Code Cj of the SDMX MeasureDimension;
258 -* The values of the SDMX simple Dimensions, TimeDimension and DataAttributes not depending on the MeasureDimension (these components by definition have always the same values for all the observations of the set above) become the values of the corresponding VTL (simple) Identifiers, (time) Identifier and Attributes.
269 +* The values of the SDMX simple Dimensions, TimeDimension and DataAttributes not depending on the MeasureDimension (these components by definition have always the same values for all the observations of the set above) become the values of the corresponding VTL (simple)
270 +
271 +Identifiers, (time) Identifier and Attributes.
272 +
259 259  * 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
260 260  * 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
261 261  
... ... @@ -348,7 +348,7 @@
348 348  The mapping table is the following:
349 349  
350 350  (% style="width:689.294px" %)
351 -|(% style="width:344px" %)**VTL**|(% style="width:341px" %)**SDMX**
365 +|(% style="width:344px" %)VTL|(% style="width:341px" %)SDMX
352 352  |(% style="width:344px" %)(Simple) Identifier|(% style="width:341px" %)Dimension
353 353  |(% style="width:344px" %)(Time) Identifier|(% style="width:341px" %)TimeDimension
354 354  |(% style="width:344px" %)Some Measures|(% style="width:341px" %)Measure
... ... @@ -408,16 +408,22 @@
408 408  
409 409  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.
410 410  
411 -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}}If these DimensionComponents would not be dropped, the various VTL Data Sets resulting from this kind of mapping would have non-matching values for the Identifiers corresponding to the mapping Dimensions (e.g. POPULATION and COUNTRY). As a consequence, taking into account that the typical binary VTL operations at dataset level (+, -, *, / and so on) are executed on the observations having matching values for the identifiers, it would not be possible to compose the resulting VTL datasets one another (e.g. it would not be possible to calculate the population ratio between USA and CANADA).{{/footnote}}. After that, the mapping method from SDMX to VTL specified for the Dataflow DF1(1.0.0) is applied (i.e. basic, pivot …).
425 +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}}If these DimensionComponents would not be dropped, the various VTL Data Sets resulting from this kind of mapping would have non-matching values for the Identifiers corresponding to the mapping Dimensions (e.g. POPULATION and COUNTRY). As a consequence, taking into account that the typical binary VTL operations at dataset level (+, -, *, / and so on) are executed on the observations having matching values for the identifiers, it would not be possible to compose the resulting VTL datasets one another (e.g. it would not be possible to calculate the population ratio between USA and CANADA).{{/footnote}}. After that, the mapping method from SDMX to VTL specified for the Dataflow DF1(1.0.0) is applied (i.e.
412 412  
413 -In the example above, for all the datasets of the kind ‘DF1(1.0.0)///INDICATORvalue//.//COUNTRYvalue//’, the dimensions INDICATOR and COUNTRY would be dropped so that the data structure of all the resulting VTL Data Sets would have the identifier TIME_PERIOD only.
427 +basic, pivot …).
414 414  
429 +In the example above, for all the datasets of the kind
430 +
431 +‘DF1(1.0.0)///INDICATORvalue//.//COUNTRYvalue//’, the dimensions INDICATOR and COUNTRY would be dropped so that the data structure of all the resulting VTL Data Sets would have the identifier TIME_PERIOD only.
432 +
415 415  It should be noted that the desired VTL Data Sets (i.e. of the kind ‘DF1(1.0.0)/// INDICATORvalue//.//COUNTRYvalue//’) can be obtained also by applying the VTL operator “**sub**” (subspace) to the Dataflow DF1(1.0.0), like in the following VTL expression:
416 416  
417 417  ‘DF1(1.0.0)/POPULATION.USA’ :=
436 +
418 418  DF1(1.0.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“USA” ];
419 419  
420 420  ‘DF1(1.0.0)/POPULATION.CANADA’ :=
440 +
421 421  DF1(1.0.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“CANADA” ];
422 422  
423 423  … … …
... ... @@ -433,6 +433,7 @@
433 433  This is equivalent to the application of the VTL “sub” operator only to the identifier //INDICATOR//:
434 434  
435 435  ‘DF1(1.0.0)/POPULATION.’ :=
456 +
436 436  DF1(1.0.0) [ sub INDICATOR=“POPULATION” ];
437 437  
438 438  Therefore the VTL Data Set ‘DF1(1.0.0)/POPULATION.’ would have the identifiers COUNTRY and TIME_PERIOD.
... ... @@ -463,8 +463,11 @@
463 463  ‘DF2(1.0.0)/GDPPERCAPITA.USA’ <- expression11; ‘DF2(1.0.0)/GDPPERCAPITA.CANADA’ <- expression12;
464 464  
465 465  … … …
487 +
466 466  ‘DF2(1.0.0)/POPGROWTH.USA’ <- expression21;
489 +
467 467  ‘DF2(1.0.0)/POPGROWTH.CANADA’ <- expression22;
491 +
468 468  … … …
469 469  
470 470  As said, it is assumed that these VTL derived Data Sets have the TIME_PERIOD as the only identifier. In the mapping from VTL to SMDX, the Dimensions INDICATOR and COUNTRY are added to the VTL data structure on order to obtain the SDMX one, with the following values respectively:
... ... @@ -612,159 +612,204 @@
612 612  
613 613  The following table describes the default mapping for converting from the SDMX data types to the VTL basic scalar types.
614 614  
615 -(% style="width:823.294px" %)
616 -|(% style="width:509px" %)**SDMX data type (BasicComponentDataType)**|(% style="width:312px" %)**Default VTL basic scalar type**
617 -|(% style="width:509px" %)(((
639 +|SDMX data type (BasicComponentDataType)|Default VTL basic scalar type
640 +|(((
618 618  String
642 +
619 619  (string allowing any character)
620 -)))|(% style="width:312px" %)string
621 -|(% style="width:509px" %)(((
644 +)))|string
645 +|(((
622 622  Alpha
647 +
623 623  (string which only allows A-z)
624 -)))|(% style="width:312px" %)string
625 -|(% style="width:509px" %)(((
649 +)))|string
650 +|(((
626 626  AlphaNumeric
652 +
627 627  (string which only allows A-z and 0-9)
628 -)))|(% style="width:312px" %)string
629 -|(% style="width:509px" %)(((
654 +)))|string
655 +|(((
630 630  Numeric
657 +
631 631  (string which only allows 0-9, but is not numeric so that is can having leading zeros)
632 -)))|(% style="width:312px" %)string
633 -|(% style="width:509px" %)(((
659 +)))|string
660 +|(((
634 634  BigInteger
662 +
635 635  (corresponds to XML Schema xs:integer datatype; infinite set of integer values)
636 -)))|(% style="width:312px" %)integer
637 -|(% style="width:509px" %)(((
664 +)))|integer
665 +|(((
638 638  Integer
639 -(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647 (inclusive))
640 -)))|(% style="width:312px" %)integer
641 -|(% style="width:509px" %)(((
667 +
668 +(corresponds to XML Schema xs:int datatype; between -2147483648 and +2147483647
669 +
670 +(inclusive))
671 +)))|integer
672 +|(((
642 642  Long
643 -(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and +9223372036854775807 (inclusive))
644 -)))|(% style="width:312px" %)integer
645 -|(% style="width:509px" %)(((
674 +
675 +(corresponds to XML Schema xs:long datatype; between -9223372036854775808 and
676 +
677 ++9223372036854775807 (inclusive))
678 +)))|integer
679 +|(((
646 646  Short
681 +
647 647  (corresponds to XML Schema xs:short datatype; between -32768 and -32767 (inclusive))
648 -)))|(% style="width:312px" %)integer
649 -|(% 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
650 -|(% style="width:509px" %)(((
683 +)))|integer
684 +|Decimal (corresponds to XML Schema xs:decimal datatype; subset of real numbers that can be represented as decimals)|number
685 +|(((
651 651  Float
687 +
652 652  (corresponds to XML Schema xs:float datatype; patterned after the IEEE single-precision 32-bit floating point type)
653 -)))|(% style="width:312px" %)number
654 -|(% style="width:509px" %)(((
689 +)))|number
690 +|(((
655 655  Double
692 +
656 656  (corresponds to XML Schema xs:double datatype; patterned after the IEEE double-precision 64-bit floating point type)
657 -)))|(% style="width:312px" %)number
658 -|(% style="width:509px" %)(((
694 +)))|number
695 +|(((
659 659  Boolean
660 -(corresponds to the XML Schema xs:boolean datatype; support the mathematical concept of binary-valued logic: {true, false})
661 -)))|(% style="width:312px" %)boolean
662 662  
663 -(% style="width:822.294px" %)
664 -|(% colspan="2" style="width:507px" %)(((
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" %)(((
665 665  URI
705 +
666 666  (corresponds to the XML Schema xs:anyURI; absolute or relative Uniform Resource Identifier Reference)
667 -)))|(% colspan="1" style="width:311px" %)string
668 -|(% colspan="2" style="width:507px" %)(((
707 +)))|(% colspan="2" %)string
708 +| |(% colspan="2" %)(((
669 669  Count
710 +
670 670  (an integer following a sequential pattern, increasing by 1 for each occurrence)
671 -)))|(% colspan="1" style="width:311px" %)integer
672 -|(% colspan="2" style="width:507px" %)(((
712 +)))|(% colspan="2" %)integer
713 +| |(% colspan="2" %)(((
673 673  InclusiveValueRange
715 +
674 674  (decimal number within a closed interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
675 -)))|(% colspan="1" style="width:311px" %)number
676 -|(% colspan="2" style="width:507px" %)(((
717 +)))|(% colspan="2" %)number
718 +| |(% colspan="2" %)(((
677 677  ExclusiveValueRange
720 +
678 678  (decimal number within an open interval, whose bounds are specified in the SDMX representation by the facets minValue and maxValue)
679 -)))|(% colspan="1" style="width:311px" %)number
680 -|(% colspan="2" style="width:507px" %)(((
722 +)))|(% colspan="2" %)number
723 +| |(% colspan="2" %)(((
681 681  Incremental
725 +
682 682  (decimal number the increased by a specific interval (defined by the interval facet), which is typically enforced outside of the XML validation)
683 -)))|(% colspan="1" style="width:311px" %)number
684 -|(% colspan="2" style="width:507px" %)(((
727 +)))|(% colspan="2" %)number
728 +| |(% colspan="2" %)(((
685 685  ObservationalTimePeriod
730 +
686 686  (superset of StandardTimePeriod and TimeRange)
687 -)))|(% colspan="1" style="width:311px" %)time
688 -|(% colspan="2" style="width:507px" %)(((
732 +)))|(% colspan="2" %)time
733 +| |(% colspan="2" %)(((
689 689  StandardTimePeriod
690 -(superset of BasicTimePeriod and ReportingTimePeriod)
691 -)))|(% colspan="1" style="width:311px" %)time
692 -|(% colspan="2" style="width:507px" %)(((
735 +
736 +(superset of BasicTimePeriod and
737 +
738 +ReportingTimePeriod)
739 +)))|(% colspan="2" %)time
740 +| |(% colspan="2" %)(((
693 693  BasicTimePeriod
742 +
694 694  (superset of GregorianTimePeriod and DateTime)
695 -)))|(% colspan="1" style="width:311px" %)date
696 -|(% colspan="2" style="width:507px" %)(((
744 +)))|(% colspan="2" %)date
745 +| |(% colspan="2" %)(((
697 697  GregorianTimePeriod
747 +
698 698  (superset of GregorianYear, GregorianYearMonth, and GregorianDay)
699 -)))|(% colspan="1" style="width:311px" %)date
700 -|(% colspan="2" style="width:507px" %)GregorianYear (YYYY)|(% colspan="1" style="width:311px" %)date
701 -|(% colspan="2" style="width:507px" %)GregorianYearMonth / GregorianMonth (YYYY-MM)|(% colspan="1" style="width:311px" %)date
702 -|(% colspan="2" style="width:507px" %)GregorianDay (YYYY-MM-DD)|(% colspan="1" style="width:311px" %)date
703 -|(% colspan="2" style="width:507px" %)(((
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" %)(((
704 704  ReportingTimePeriod
705 -(superset of RepostingYear, ReportingSemester, ReportingTrimester, ReportingQuarter, ReportingMonth, ReportingWeek, ReportingDay)
706 -)))|(% colspan="1" style="width:311px" %)time_period
707 -|(% colspan="2" style="width:507px" %)(((
755 +
756 +(superset of RepostingYear, ReportingSemester,
757 +
758 +ReportingTrimester, ReportingQuarter,
759 +
760 +ReportingMonth, ReportingWeek, ReportingDay)
761 +)))|(% colspan="2" %)time_period
762 +| |(% colspan="2" %)(((
708 708  ReportingYear
764 +
709 709  (YYYY-A1 – 1 year period)
710 -)))|(% colspan="1" style="width:311px" %)time_period
711 -|(% colspan="2" style="width:507px" %)(((
766 +)))|(% colspan="2" %)time_period
767 +| |(% colspan="2" %)(((
712 712  ReportingSemester
769 +
713 713  (YYYY-Ss – 6 month period)
714 -)))|(% colspan="1" style="width:311px" %)time_period
715 -|(% colspan="2" style="width:507px" %)(((
771 +)))|(% colspan="2" %)time_period
772 +| |(% colspan="2" %)(((
716 716  ReportingTrimester
774 +
717 717  (YYYY-Tt – 4 month period)
718 -)))|(% colspan="1" style="width:311px" %)time_period
719 -|(% colspan="2" style="width:507px" %)(((
776 +)))|(% colspan="2" %)time_period
777 +| |(% colspan="2" %)(((
720 720  ReportingQuarter
779 +
721 721  (YYYY-Qq – 3 month period)
722 -)))|(% colspan="1" style="width:311px" %)time_period
723 -|(% colspan="2" style="width:507px" %)(((
781 +)))|(% colspan="2" %)time_period
782 +| |(% colspan="2" %)(((
724 724  ReportingMonth
784 +
725 725  (YYYY-Mmm – 1 month period)
726 -)))|(% colspan="1" style="width:311px" %)time_period
727 -|(% colspan="2" style="width:507px" %)ReportingWeek|(% colspan="1" style="width:311px" %)time_period
728 -|(% 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" %)
729 -|(% colspan="1" style="width:507px" %)(((
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" %)(((
730 730  ReportingDay
793 +
731 731  (YYYY-Dddd – 1 day period)
732 -)))|(% colspan="2" style="width:312px" %)time_period
733 -|(% colspan="1" style="width:507px" %)(((
795 +)))|(% colspan="2" %)time_period|
796 +|(% colspan="2" %)(((
734 734  DateTime
798 +
735 735  (YYYY-MM-DDThh:mm:ss)
736 -)))|(% colspan="2" style="width:312px" %)date
737 -|(% colspan="1" style="width:507px" %)(((
800 +)))|(% colspan="2" %)date|
801 +|(% colspan="2" %)(((
738 738  TimeRange
803 +
739 739  (YYYY-MM-DD(Thh:mm:ss)?/<duration>)
740 -)))|(% colspan="2" style="width:312px" %)time
741 -|(% colspan="1" style="width:507px" %)(((
805 +)))|(% colspan="2" %)time|
806 +|(% colspan="2" %)(((
742 742  Month
808 +
743 743  (~-~-MM; speicifies a month independent of a year; e.g. February is black history month in the United States)
744 -)))|(% colspan="2" style="width:312px" %)string
745 -|(% colspan="1" style="width:507px" %)(((
810 +)))|(% colspan="2" %)string|
811 +|(% colspan="2" %)(((
746 746  MonthDay
813 +
747 747  (~-~-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)
748 -)))|(% colspan="2" style="width:312px" %)string
749 -|(% colspan="1" style="width:507px" %)(((
815 +)))|(% colspan="2" %)string|
816 +|(% colspan="2" %)(((
750 750  Day
818 +
751 751  (~-~--DD; specifies a day independent of a month or year; e.g. the 15^^th^^ is payday)
752 -)))|(% colspan="2" style="width:312px" %)string
753 -|(% colspan="1" style="width:507px" %)(((
820 +)))|(% colspan="2" %)string|
821 +|(% colspan="2" %)(((
754 754  Time
823 +
755 755  (hh:mm:ss; time independent of a date; e.g. coffee break is at 10:00 AM)
756 -)))|(% colspan="2" style="width:312px" %)string
757 -|(% colspan="1" style="width:507px" %)(((
825 +)))|(% colspan="2" %)string|
826 +|(% colspan="2" %)(((
758 758  Duration
828 +
759 759  (corresponds to XML Schema xs:duration datatype)
760 -)))|(% colspan="2" style="width:312px" %)duration
761 -|(% colspan="1" style="width:507px" %)XHTML|(% colspan="2" style="width:312px" %)Metadata type – not applicable
762 -|(% colspan="1" style="width:507px" %)KeyValues|(% colspan="2" style="width:312px" %)Metadata type – not applicable
763 -|(% colspan="1" style="width:507px" %)IdentifiableReference|(% colspan="2" style="width:312px" %)Metadata type – not applicable
764 -|(% colspan="1" style="width:507px" %)DataSetReference|(% colspan="2" style="width:312px" %)Metadata type – not applicable
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|
765 765  
766 -(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes" %)
767 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
836 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
768 768  
769 769  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).
770 770  
... ... @@ -772,32 +772,39 @@
772 772  
773 773  The following table describes the default conversion from the VTL basic scalar types to the SDMX data types .
774 774  
775 -(% style="width:1073.29px" %)
776 -|(% style="width:207px" %)(((
777 -**VTL basic scalar type**
778 -)))|(% style="width:462px" %)(((
779 -**Default SDMX data type (BasicComponentDataType)**
780 -)))|(% style="width:402px" %)**Default output format**
781 -|(% style="width:207px" %)String|(% style="width:462px" %)String|(% style="width:402px" %)Like XML (xs:string)
782 -|(% style="width:207px" %)Number|(% style="width:462px" %)Float|(% style="width:402px" %)Like XML (xs:float)
783 -|(% style="width:207px" %)Integer|(% style="width:462px" %)Integer|(% style="width:402px" %)Like XML (xs:int)
784 -|(% style="width:207px" %)Date|(% style="width:462px" %)DateTime|(% style="width:402px" %)YYYY-MM-DDT00:00:00Z
785 -|(% style="width:207px" %)Time|(% style="width:462px" %)StandardTimePeriod|(% style="width:402px" %)<date>/<date> (as defined above)
786 -|(% style="width:207px" %)time_period|(% style="width:462px" %)(((
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|(((
787 787  ReportingTimePeriod
862 +
788 788  (StandardReportingPeriod)
789 -)))|(% style="width:402px" %)(((
864 +)))|(((
790 790  YYYY-Pppp
866 +
791 791  (according to SDMX )
792 792  )))
793 -|(% style="width:207px" %)Duration|(% style="width:462px" %)Duration|(% style="width:402px" %)(((
869 +|Duration|Duration|(((
794 794  Like XML (xs:duration)
871 +
795 795  PnYnMnDTnHnMnS
796 796  )))
797 -|(% style="width:207px" %)Boolean|(% style="width:462px" %)Boolean|(% style="width:402px" %)Like XML (xs:boolean) with the values "true" or "false"
874 +|Boolean|Boolean|Like XML (xs:boolean) with the values "true" or "false"
798 798  
799 -(% class="wikigeneratedid" id="HFigure142013MappingsfromSDMXdatatypestoVTLBasicScalarTypes-1" %)
800 -**Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types**
876 +==== Figure 14 – Mappings from SDMX data types to VTL Basic Scalar Types ====
801 801  
802 802  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).
803 803  
... ... @@ -851,7 +851,7 @@
851 851  |N|fixed number of digits used in the preceding textual representation of the month or the day
852 852  | |
853 853  
854 -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}}.
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"]](%%)^^.
855 855  
856 856  === 12.4.5 Null Values ===
857 857  
... ... @@ -869,8 +869,10 @@
869 869  
870 870  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).
871 871  
872 -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.
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
873 873  
950 +TransformationScheme.
951 +
874 874  In case a literal is operand of a VTL Cast operation, the format specified in the Cast overrides all the possible otherwise specified formats.
875 875  
876 876  {{putFootnotes/}}