Changes for page 12 Validation and Transformation Language (VTL)
Last modified by Helena on 2025/09/10 11:19
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... ... @@ -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 351 +|(% 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 ... ... @@ -408,22 +408,16 @@ 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. 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 …). 412 412 413 -basi c, pivot…).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. 414 414 415 -In the example above, for all the datasets of the kind 416 - 417 -‘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. 418 - 419 419 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: 420 420 421 421 ‘DF1(1.0.0)/POPULATION.USA’ := 422 - 423 423 DF1(1.0.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“USA” ]; 424 424 425 425 ‘DF1(1.0.0)/POPULATION.CANADA’ := 426 - 427 427 DF1(1.0.0) [ sub INDICATOR=“POPULATION”, COUNTRY=“CANADA” ]; 428 428 429 429 … … … ... ... @@ -439,7 +439,6 @@ 439 439 This is equivalent to the application of the VTL “sub” operator only to the identifier //INDICATOR//: 440 440 441 441 ‘DF1(1.0.0)/POPULATION.’ := 442 - 443 443 DF1(1.0.0) [ sub INDICATOR=“POPULATION” ]; 444 444 445 445 Therefore the VTL Data Set ‘DF1(1.0.0)/POPULATION.’ would have the identifiers COUNTRY and TIME_PERIOD. ... ... @@ -470,11 +470,8 @@ 470 470 ‘DF2(1.0.0)/GDPPERCAPITA.USA’ <- expression11; ‘DF2(1.0.0)/GDPPERCAPITA.CANADA’ <- expression12; 471 471 472 472 … … … 473 - 474 474 ‘DF2(1.0.0)/POPGROWTH.USA’ <- expression21; 475 - 476 476 ‘DF2(1.0.0)/POPGROWTH.CANADA’ <- expression22; 477 - 478 478 … … … 479 479 480 480 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: