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1 {{box title="**Contents**"}}
2 {{toc/}}
3 {{/box}}
4
5 == 13.1 Introduction ==
6
7 The purpose of SDMX structure mapping is to transform datasets from one dimensionality to another. In practice, this means that the input and output datasets conform to different Data Structure Definition.
8
9 Structure mapping does not alter the observation values and is not intended to perform any aggregations or calculations.
10
11 An input series maps to:
12
13 1. Exactly one output series; or
14 1. Multiple output series with different Series Keys, but the same observation values; or
15 1. Zero output series where no source rule matches the input Component values.
16
17 Typical use cases include:
18
19 * Transforming received data into a common internal structure;
20 * Transforming reported data into the data collector's preferred structure;
21 * Transforming unidimensional datasets{{footnote}}Unidimensional datasets are those with a single 'indicator' or 'series code' dimension.{{/footnote}} to multi-dimensional; and
22 * Transforming internal datasets with a complex structure to a simpler structure with fewer dimensions suitable for dissemination.
23
24 == 13.2 1-1 structure maps ==
25
26 1-1 (pronounced 'one to one') mappings support the simple use case where the value of a Component in the source structure is translated to a different value in the target, usually where different classification schemes are used for the same Concept.
27
28 In the example below, ISO 2-character country codes are mapped to their ISO 3character equivalent.
29
30 (% style="width:666.294px" %)
31 |(% style="width:217px" %)**Country**|(% style="width:251px" %)**Alpha-2 code**|(% style="width:195px" %)**Alpha-3 code**
32 |(% style="width:217px" %)Afghanistan|(% style="width:251px" %)AF|(% style="width:195px" %)AFG
33 |(% style="width:217px" %)Albania|(% style="width:251px" %)AL|(% style="width:195px" %)ALB
34 |(% style="width:217px" %)Algeria|(% style="width:251px" %)DZ|(% style="width:195px" %)DZA
35 |(% style="width:217px" %)American Samoa|(% style="width:251px" %)AS|(% style="width:195px" %)ASM
36 |(% style="width:217px" %)Andorra|(% style="width:251px" %)AD|(% style="width:195px" %)AND
37 |(% style="width:217px" %)etc…|(% style="width:251px" %) |(% style="width:195px" %)
38
39 Different source values can also map to the same target value, for example when deriving regions from country codes.
40
41 (% style="width:674.294px" %)
42 |(% style="width:284px" %)**Source Component: REF_AREA**|(% style="width:387px" %)**Target Component: REGION**
43 |(% style="width:284px" %)FR|(% style="width:387px" %)EUR
44 |(% style="width:284px" %)DE|(% style="width:387px" %)EUR
45 |(% style="width:284px" %)IT|(% style="width:387px" %)EUR
46 |(% style="width:284px" %)ES|(% style="width:387px" %)EUR
47 |(% style="width:284px" %)BE|(% style="width:387px" %)EUR
48
49 == 13.3 N-n structure maps ==
50
51 N-n (pronounced 'N to N') mappings describe rules where a specified combination of values in multiple source Components map to specified values in one or more target Components. For example, when mapping a partial Series Key from a highly multidimensional cube (like Balance of Payments) to a single 'Indicator' Dimension in a target Data Structure.
52
53 Example:
54
55 (% style="width:760.294px" %)
56 |(% style="width:58px" %)**Rule**|(% style="width:384px" %)**Source**|(% style="width:313px" %)**Target**
57 |(% style="width:58px" %)1|(% style="width:384px" %)(((
58 If
59 FREQUENCY=A; and ADJUSTMENT=N; and MATURITY=L.
60 )))|(% style="width:313px" %)(((
61 Set
62 INDICATOR=A_N_L
63 )))
64 |(% style="width:58px" %)2|(% style="width:384px" %)(((
65 If
66 FREQUENCY=M; and ADJUSTMENT=S_A1; and MATURITY=TY12.
67 )))|(% style="width:313px" %)(((
68 Set
69 INDICATOR=MON_SAX_12
70 )))
71
72 N-n rules can also set values for multiple source Components.
73
74 (% style="width:757.294px" %)
75 |(% style="width:62px" %)**Rule**|(% style="width:378px" %)**Source**|(% style="width:312px" %)**Target**
76 |(% style="width:62px" %)1|(% style="width:378px" %)(((
77 If
78 FREQUENCY=A; and ADJUSTMENT=N; and MATURITY=L.
79 )))|(% style="width:312px" %)(((
80 Set
81 INDICATOR=A_N_L,
82 STATUS=QXR15,
83 NOTE="Unadjusted".
84 )))
85 |(% style="width:62px" %)2|(% style="width:378px" %)(((
86 If
87 FREQUENCY=M; and ADJUSTMENT=S_A1; and MATURITY=TY12.
88 )))|(% style="width:312px" %)(((
89 Set
90 INDICATOR=MON_SAX_12, STATUS=MPM12,
91 NOTE="Seasonally Adjusted"
92 )))
93
94 == 13.4 Ambiguous mapping rules ==
95
96 A structure map is ambiguous if the rules result in a dataset containing multiple series with the same Series Key.
97
98 A simple example mapping a source dataset with a single dimension to one with multiple dimensions is shown below:
99
100 (% style="width:819.294px" %)
101 |(% style="width:240px" %)**Source**|(% style="width:246px" %)**Target**|(% style="width:329px" %)**Output Series Key**
102 |(% style="width:240px" %)SERIES_CODE=XMAN_Z_21|(% style="width:246px" %)(((
103 Dimensions
104 INDICATOR=XM
105 FREQ=A
106 ADJUSTMENT=N
107 Attributes
108 UNIT_MEASURE=_Z
109 COMP_ORG=21
110 )))|(% style="width:329px" %)XM:A:N
111 |(% style="width:240px" %)SERIES_CODE=XMAN_Z_34|(% style="width:246px" %)(((
112 Dimensions
113 INDICATOR=XM
114 FREQ=A
115 ADJUSTMENT=N
116 Attributes
117 UNIT_MEASURE=_Z
118 COMP_ORG=34
119 )))|(% style="width:329px" %)XM:A:N
120
121 The above behaviour can be okay if the series XMAN_Z_21 contains observations for different periods of time then the series XMAN_Z_34. If however both series contain observations for the same point in time, the output for this mapping will be two observations with the same series key, for the same period in time.
122
123 == 13.5 Representation maps ==
124
125 Representation Maps replace the SDMX 2.1 Codelist Maps and are used describe explicit mappings between source and target Component values.
126
127 The source and target of a Representation Map can reference any of the following:
128
129 1. Codelist
130 1. Free Text (restricted by type, e.g String, Integer, Boolean)
131 1. Valuelist
132
133 A Representation Map mapping ISO 2-character to ISO 3-character Codelists would take the following form:
134
135 (% style="width:763.294px" %)
136 |(% style="width:252px" %)**CL_ISO_ALPHA2**|(% style="width:508px" %)**CL_ISO_ALPHA3**
137 |(% style="width:252px" %)AF|(% style="width:508px" %)AFG
138 |(% style="width:252px" %)AL|(% style="width:508px" %)ALB
139 |(% style="width:252px" %)DZ|(% style="width:508px" %)DZA
140 |(% style="width:252px" %)AS|(% style="width:508px" %)ASM
141 |(% style="width:252px" %)AD|(% style="width:508px" %)AND
142 |(% style="width:252px" %)etc…|(% style="width:508px" %)
143
144 A Representation Map mapping free text country names to an ISO 2-character Codelist could be similarly described:
145
146 (% style="width:770.294px" %)
147 |(% style="width:247px" %)**Text**|(% style="width:520px" %)**CL_ISO_ALPHA2**
148 |(% style="width:247px" %)"Germany"|(% style="width:520px" %)DE
149 |(% style="width:247px" %)"France"|(% style="width:520px" %)FR
150 |(% style="width:247px" %)"United Kingdom"|(% style="width:520px" %)GB
151 |(% style="width:247px" %)"Great Britain"|(% style="width:520px" %)GB
152 |(% style="width:247px" %)"Ireland"|(% style="width:520px" %)IE
153 |(% style="width:247px" %)"Eire"|(% style="width:520px" %)IE
154 |(% style="width:247px" %)etc…|(% style="width:520px" %)
155
156 Valuelists, introduced in SDMX 3.0, are equivalent to Codelists but allow the maintenance of non-SDMX identifiers. Importantly, their IDs do not need to conform to IDType, but as a consequence are not Identifiable.
157
158 When used in Representation Maps, Valuelists allow Non-SDMX identifiers containing characters like £, $, % to be mapped to Code IDs, or Codes mapped to non-SDMX identifiers.
159
160 In common with Codelists, each item in a Valuelist has a multilingual name giving it a human-readable label and an optional description. For example:
161
162 (% style="width:780.294px" %)
163 |(% style="width:126px" %)**Value**|(% style="width:153px" %)**Locale**|(% style="width:498px" %)**Name**
164 |(% style="width:126px" %)$|(% style="width:153px" %)en|(% style="width:498px" %)United States Dollar
165 |(% style="width:126px" %)%|(% style="width:153px" %)En|(% style="width:498px" %)Percentage
166 |(% style="width:126px" %) |(% style="width:153px" %)fr|(% style="width:498px" %)Pourcentage
167
168 Other characteristics of Representation Maps:
169
170 * Support the mapping of multiple source Component values to multiple Target Component values as described in section 13.3 on n-to-n mappings; this covers also the case of mapping an Attribute with an array representation to map combinations of values to a single target value;
171 * Allow source or target mappings for an Item to be optional allowing rules such as 'A maps to nothing' or 'nothing maps to A'; and
172 * Support for mapping rules where regular expressions or substrings are used to match source Component values. Refer to section 13.6 for more on this topic.
173
174 == 13.6 Regular expression and substring rules ==
175
176 It is common for classifications to contain meanings within the identifier, for example the code Id 'XULADS' may refer to a particular seasonality because it starts with the letters XU.
177
178 With SDMX 2.1 each code that starts with XU had to be individually mapped to the same seasonality, and additional mappings added when new Codes were added to the Codelists. This led to many hundreds or thousands of mappings which can be more efficiently summarised in a single conceptual rule:
179
180 //If starts with 'XU' map to 'Y'//
181
182 These rules are described using either regular expressions, or substrings for simpler use cases.
183
184 === 13.6.1 Regular expressions ===
185
186 Regular expression mapping rules are defined in the Representation Map.
187
188 Below is an example set of regular expression rules for a particular component.
189
190 |Regex|Description|Output
191 |A|Rule match if input = 'A'|OUT_A
192 |^[A-G]|Rule match if the input starts with letters A to G|OUT_B
193 |A~|B|Rule match if input is either 'A' or 'B'|OUT_C
194
195 Like all mapping rules, the output is either a Code, a Value or free text depending on the representation of the Component in the target Data Structure Definition.
196
197 If the regular expression contains capture groups, these can be used in the definition of the output value, by specifying \//**n** //as an output value where //**n**// is the number of the capture group starting from 1. For example
198
199 |Regex|Target output|Example Input|Example Output
200 |(((
201 ([0-9]{4})[0-
202
203 9]([0-9]{1})
204 )))|\1-Q\2|200933|2009-Q3
205
206 As regular expression rules can be used as a general catch-all if nothing else matches, the ordering of the rules is important. Rules should be tested starting with the highest priority, moving down the list until a match is found.
207
208 The following example shows this:
209
210 |Priority|Regex|Description|Output
211 |1|A|Rule match if input = 'A'|OUT_A
212 |2|B|Rule match if input = 'B'|OUT_B
213 |3|[A-Z]|Any character A-Z|OUT_C
214
215 The input 'A' matches both the first and the last rule, but the first takes precedence having the higher priority. The output is OUT_A.
216
217 The input 'G' matches on the last rule which is used as a catch-all or default in this example.
218
219 === 13.6.2 Substrings ===
220
221 Substrings provide an alternative to regular expressions where the required section of an input value can be described using the number of the starting character, and the length of the substring in characters. The first character is at position 1.
222
223 For instance:
224
225 |Input String|Start|Length|Output
226 |ABC_DEF_XYZ|5|3|DEF
227 |XULADS|1|2|XU
228
229 Sub-strings can therefore be used for the conceptual rule //If starts with 'XU' map to Y// as shown in the following example:
230
231 |Start|Length|Source|Target
232 |1|2|XU|Y
233
234 == 13.7 Mapping non-SDMX time formats to SDMX formats ==
235
236 Structure mapping allows non-SDMX compliant time values in source datasets to be mapped to an SDMX compliant time format.
237
238 Two types of time input are defined:
239
240 a. **Pattern based dates** – a string which can be described using a notation like dd/mm/yyyy or is represented as the number of periods since a point in time, for example: 2010M001 (first month in 2010), or 2014D123 (123^^rd^^ day in 2014); and b. **Numerical based datetime** – a number specifying the elapsed periods since a fixed point in time, for example Unix Time is measured by the number of milliseconds since 1970.
241
242 The output of a time-based mapping is derived from the output Frequency, which is either explicitly stated in the mapping or defined as the value output by a specific Dimension or Attribute in the output mapping. If the output frequency is unknown or if the SDMX format is not desired, then additional rules can be provided to specify the output date format for the given frequency Id. The default rules are:
243
244 |Frequency|Format|Example
245 |A|YYYY|2010
246 |D|YYYY-MM-DD|2010-01-01
247 |I|YYYY-MM-DDThh:mm:ss|2010-01T20:22:00
248 |M|YYYY-MM|2010-01
249 |Q|YYYY-Qn|2010-Q1
250 |S|YYYY-Sn|2010-S1
251 |T|YYYY-Tn|2010-T1
252 |W|YYYY-Wn|YYYY-W53
253
254 In the case where the input frequency is lower than the output frequency, the mapping defaults to end of period, but can be explicitly set to start, end or mid-period.
255
256 There are two important points to note:
257
258 1. The output frequency determines the output date format, but the default output can be redefined using a Frequency Format mapping to force explicit rules on how the output time period is formatted.
259 1. To support the use case of changing frequency the structure map can optionally provide a start of year attribute, which defines the year start date in MM-DD format. For example: YearStart=04-01.
260
261 === 13.7.1 Pattern based dates ===
262
263 Date and time formats are specified by date and time pattern strings based on Java's Simple Date Format. Within date and time pattern strings, unquoted letters from 'A' to 'Z' and from 'a' to 'z' are interpreted as pattern letters representing the components of a date or time string. Text can be quoted using single quotes (') to avoid interpretation. "''" represents a single quote. All other characters are not interpreted; they're simply copied into the output string during formatting or matched against the input string during parsing.
264
265 Due to the fact that dates may differ per locale, an optional property, defining the locale of the pattern, is provided. This would assist processing of source dates, according to the given locale^^[[(% class="wikiinternallink wikiinternallink wikiinternallink" %)^^44^^>>path:#sdfootnote44sym||name="sdfootnote44anc"]](%%)^^. An indicative list of examples is presented in the following table:
266
267 |English (en)|Australia (AU)|en-AU
268 |English (en)|Canada (CA)|en-CA
269 |English (en)|United Kingdom (GB)|en-GB
270 |English (en)|United States (US)|en-US
271 |Estonian (et)|Estonia (EE)|et-EE
272 |Finnish (fi)|Finland (FI)|fi-FI
273 |French (fr)|Belgium (BE)|fr-BE
274 |French (fr)|Canada (CA)|fr-CA
275 |French (fr)|France (FR)|fr-FR
276 |French (fr)|Luxembourg (LU)|fr-LU
277 |French (fr)|Switzerland (CH)|fr-CH
278 |German (de)|Austria (AT)|de-AT
279 |German (de)|Germany (DE)|de-DE
280
281 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_59eee18f.gif||alt="Shape8" height="1" width="192"]]
282
283 |German (de)|Luxembourg (LU)|de-LU
284 |German (de)|Switzerland (CH)|de-CH
285 |Greek (el)|Cyprus (CY)|el-CY[[__(*)__>>url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]][[url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]]
286 |Greek (el)|Greece (GR)|el-GR
287 |Hebrew (iw)|Israel (IL)|iw-IL
288 |Hindi (hi)|India (IN)|hi-IN
289 |Hungarian (hu)|Hungary (HU)|hu-HU
290 |Icelandic (is)|Iceland (IS)|is-IS
291 |Indonesian (in)|Indonesia (ID)|in-ID[[__(*)__>>url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]][[url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]]
292 |Irish (ga)|Ireland (IE)|ga-IE[[__(*)__>>url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]][[url:https://www.oracle.com/java/technologies/javase/jdk8-jre8-suported-locales.html#cldrlocale]]
293 |Italian (it)|Italy (IT)|it-IT
294
295 Examples
296
297 22/06/1981 would be described as dd/MM/YYYY, with locale en-GB
298
299 2008-mars-12 would be described as YYYY-MMM-DD, with locale fr-FR
300
301 22 July 1981 would be described as dd MMMM YYYY, with locale en-US
302
303 22 Jul 1981 would be described as dd MMM YYYY
304
305 2010 D62 would be described as YYYYDnn (day 62 of the year 2010)
306
307 The following pattern letters are defined (all other characters from 'A' to 'Z' and from 'a' to 'z' are reserved):
308
309 |Letter|Date or Time Component|Presentation|Examples
310 |G|Era designator|[[Text>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#text]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#text]]|AD
311 |yy|Year short (upper case is Year of Week^^[[(% class="wikiinternallink wikiinternallink wikiinternallink" %)^^45^^>>path:#sdfootnote45sym||name="sdfootnote45anc"]](%%)^^)|[[Year>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#year]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#year]]|96
312 |yyyy|Year Full (upper case is Year of Week)|Year|1996
313 |MM|Month number in year starting with 1|Month|07
314 |MMM|Month name short|Month|Jul
315 |MMMM|Month name full|Month|July
316 |ww|Week in year|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|27
317 |W|Week in month|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|2
318 |DD|Day in year|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|189
319 |dd|Day in month|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|10
320 |F|Day of week in month|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|2
321 |E|Day name in week|[[Text>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#text]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#text]]|Tuesday; Tue
322
323 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_59eee18f.gif||alt="Shape9" height="1" width="192"]]
324
325 |U|Day number of week (1 = Monday, ..., 7 = Sunday)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|1
326 |HH|Hour in day (0-23)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|0
327 |kk|Hour in day (1-24)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|24
328 |KK|Hour in am/pm (0-11)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|0
329 |hh|Hour in am/pm (1-12)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|12
330 |mm|Minute in hour|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|30
331 |ss|Second in minute|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|55
332 |S|Millisecond|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|978
333 |n|Number of periods, used after a SDMX Frequency Identifier such as M, Q, D (month, quarter, day)|[[Number>>url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]][[url:https://docs.oracle.com/javase/7/docs/api/java/text/SimpleDateFormat.html#number]]|12
334
335 The model is illustrated below:
336
337 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_295af259.jpg||height="265" width="477"]]
338
339 ==== Figure 24 showing the component map mapping the SOURCE_DATE Dimension to the TIME_PERIOD dimension with the additional information on the component map to describe the time format ====
340
341 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_a3215c79.jpg||height="265" width="480"]]
342
343 ==== Figure 25 showing an input date format, whose output frequency is derived from the output value of the FREQ Dimension ====
344
345 === 13.7.2 Numerical based datetime ===
346
347 Where the source datetime input is purely numerical, the mapping rules are defined by the **Base** as a valid SDMX Time Period, and the **Period** which must take one of the following enumerated values:
348
349 * day
350 * second
351 * millisecond
352 * microsecond
353 * nanosecond
354
355 |Numerical datetime systems|Base|Period
356 |(((
357 Epoch Time (UNIX)
358
359 Milliseconds since 01 Jan 1970
360 )))|1970|millisecond
361 |(((
362 Windows System Time
363
364 Milliseconds since 01 Jan 1601
365 )))|1601|millisecond
366
367 The example above illustrates numerical based datetime mapping rules for two commonly used time standards.
368
369 The model is illustrated below:
370
371 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_ab51b44a.jpg||height="113" width="485"]]
372
373 **Figure 26 showing the component map mapping the SOURCE_DATE Dimension to the**
374
375 ==== TIME_PERIOD Dimension with the additional information on the component map to describe the numerical datetime system in use ====
376
377 === 13.7.3 Mapping more complex time inputs ===
378
379 VTL should be used for more complex time inputs that cannot be interpreted using the pattern based on numerical methods.
380
381 == 13.8 Using TIME_PERIOD in mapping rules ==
382
383 The source TIME_PERIOD Dimension can be used in conjunction with other input Dimensions to create discrete mapping rules where the output is conditional on the time period value.
384
385 The main use case is setting the value of Observation Attributes in the target dataset.
386
387 |Rule|Source|Target
388 |1|(((
389 If
390
391 INDICATOR=XULADS; and TIME_PERIOD=2007.
392 )))|(((
393 Set
394
395 OBS_CONF=F
396 )))
397 |2|(((
398 If
399
400 INDICATOR=XULADS; and TIME_PERIOD=2008.
401 )))|(((
402 Set
403
404 OBS_CONF=F
405 )))
406 |3|(((
407 If
408
409 INDICATOR=XULADS; and TIME_PERIOD=2009.
410 )))|(((
411 Set
412
413 OBS_CONF=F
414 )))
415 |4|(((
416 If
417
418 INDICATOR=XULADS; and TIME_PERIOD=2010.
419 )))|(((
420 Set
421
422 OBS_CONF=**C**
423 )))
424
425 In the example above, OBS_CONF is an Observation Attribute.
426
427 == 13.9 Time span mapping rules using validity periods ==
428
429 Creating discrete mapping rules for each TIME_PERIOD is impractical where rules need to cover a specific span of time regardless of frequency, and for high-frequency data.
430
431 Instead, an optional validity period can be set for each mapping.
432
433 By specifying validity periods, the example from Section 13.8 can be re-written using two rules as follows:
434
435 |Rule|Source|Target
436 |1|(((
437 If
438
439 INDICATOR=XULADS.
440
441 Validity Period start period=2007 end period=2009
442 )))|(((
443 Set
444
445 OBS_CONF=F
446 )))
447 |2|(((
448 If
449
450 INDICATOR=XULADS.
451
452 Validity Period start period=2010
453 )))|(((
454 Set
455
456 OBS_CONF=F** **
457 )))
458
459 In Rule 1, start period resolves to the start of the 2007 period (2007-01-01T00:00:00), and the end period resolves to the very end of 2009 (2009-12-31T23:59:59). The rule will hold true regardless of the input data frequency. Any observations reporting data for the Indicator XULADS that fall into that time range will have an OBS_CONF value of F.
460
461 In Rule 2, no end period is specified so remains in effect from the start of the period (2010-01-01T00:00:00) until the end of time. Any observations reporting data for the Indicator XULADS that fall into that time range will have an OBS_CONF value of C.
462
463 == 13.10 Mapping examples ==
464
465 === 13.10.1 Many to one mapping (N-1) ===
466
467 |Source|Map To
468 |(((
469 **FREQ**="A"
470
471 ADJUSTMENT="N"
472
473 **REF_AREA**="PL"
474
475 **COUNTERPART_AREA**="W0"
476
477 REF_SECTOR="S1"
478
479 COUNTERPART_SECTOR="S1" ACCOUNTING_ENTRY="B"
480
481 STO="B5G"
482 )))|(((
483 FREQ="A"
484
485 REF_AREA="PL"
486
487 COUNTERPART_AREA="W0"
488
489 INDICATOR="IND_ABC"
490 )))
491
492 The bold Dimensions map from source to target verbatim. The mapping simply specifies:
493
494 FREQ => FREQ
495
496 REF_AREA=> REF_AREA
497
498 COUNTERPART_AREA=> COUNTERPART _AREA
499
500 No Representation Mapping is required. The source value simply copies across unmodified.
501
502 The remaining Dimensions all map to the Indicator Dimension. This is an example of many Dimensions mapping to one Dimension. In this case a Representation Mapping is required, and the mapping first describes the input 'partial key' and how this maps to the target indicator:
503
504 N:S1:S1:B:B5G => IND_ABC
505
506 Where the key sequence is based on the order specified in the mapping (i.e ADJUSTMENT, REF_SECTOR, etc will result in the first value N being taken from ADJUSTMENT as this was the first item in the source Dimension list.
507
508 **Note**: The key order is NOT based on the Dimension order of the DSD, as the mapping needs to be resilient to the DSD changing.
509
510 === 13.10.2 Mapping other data types to Code Id ===
511
512 In the case where the incoming data type is not a string and not a code identifier i.e. the source Dimension is of type Integer and the target is Codelist. This is supported by the RepresentationMap. The RepresentationMap source can reference a Codelist, Valuelist, or be free text, the free text can include regular expressions.
513
514 The following representation mapping can be used to explicitly map each age to an output code.
515
516 :
517
518 (((
519 |Source Input Free Text|Desired Output Code Id
520 |0|A
521 |1|A
522 |2|A
523 |3|B
524 |4|B
525 )))
526
527 If this mapping takes advantage of regular expressions it can be expressed in two 3464 rules:
528
529 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_8c1afe2b.gif||alt="Shape10" height="1" width="302"]]
530
531 __Regular Expression __Desired Output
532
533 :
534
535 (((
536 |[0-2]|A
537 |[3-4]|B
538 )))
539
540 === 13.10.3 Observation Attributes for Time Period ===
541
542 This use case is where a specific observation for a specific time period has an attribute 3468 value.
543
544 :
545
546 (((
547 |Input INDICATOR|Input TIME_PERIOD|Output OBS_CONF
548 |XULADS|2008|C
549 |XULADS|2009|C
550 |XULADS|2010|C
551 )))
552
553 __Or using a validity period on the Representation Mapping__:
554
555 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_6dbf7f.gif||alt="Shape11" height="36" width="555"]] Input INDICATOR Valid From/ Valid To Output OBS_CONF
556
557 XULADS 2008/2010 C
558
559 === 13.10.4 Time mapping ===
560
561 This use case is to create a time period from an input that does not respect SDMXTime Formats.
562
563 The Component Mapping from SYS_TIME to TIME_PERIOD specifies itself as a time mapping with the following details:
564
565 :
566
567 (((
568 |Source Value|Source Mapping|Target Frequency|Output
569 |18/07/1981|dd/MM/yyyy|A|1981
570 )))
571
572 When the target frequency is based on another target Dimension value, in this example __the value of the FREQ Dimension in the tar__get DSD.
573
574 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_dbe68698.gif||alt="Shape12" height="1" width="273"]]
575
576 :
577 ::
578
579 (((
580 |Source Value|Source Mapping|Target Frequency Output Dimension
581
582 |18/07/1981 dd/MM/yyyy|FREQ| |1981-07-18 (when FREQ=D)
583 |(% rowspan="2" %)(((
584 __When the source is a numerical form__at
585
586 Source Value Start Period Interv
587 )))| | |
588 |al|(((
589 Target
590
591 FREQ
592 )))|Output
593 |(% colspan="2" %)1589808220 1970 millisecond|M|2020-05
594 )))
595
596 When the source frequency is lower than the target frequency additional information 3485 can be provided for resolve to start of period, end of period, or mid period, as shown 3486 in the following example:
597
598 Source Value Source Mapping Target Frequency Output
599
600 Dimension
601
602 [[image:SDMX 3-0-0 SECTION 6 FINAL-1.0_en_4ec4bb31.gif||alt="Shape13" height="173" width="555"]] 1981 yyyy D – End of Period 1981-12-31
603
604 When the start of year is April 1^^st^^ the Structure Map has YearStart=04-01:
605
606 Source Value Source Mapping Target Frequency Output
607
608 Dimension
609
610 1981 yyyy D – End of Period 1982-03-31
611
612 {{putFootnotes/}}