Wiki source code of 8 Hierarchy

Version 15.2 by Helena K. on 2026/06/05 10:48

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3.2	1	{{box title="Contents"}}
	2	{{toc/}}
	3	{{/box}}
1.1	4
3.2	5	== 8.1 Scope ==
1.1	6
15.2	7	The [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] described in the section on structural definitions supports a simple [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] of Codes and restricts any [[child>>doc:IMElements.child.WebHome]] [[Code>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.Item.Code.WebHome]] to having just one [[parent>>doc:IMElements.parent.WebHome]] [[Code>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.Item.Code.WebHome]]. Whilst this [[structure>>doc:IMElements.structure.WebHome]] is useful for supporting the needs of the [[DataStructureDefinition>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.VersionableArtefact.MaintainableArtefact.Structure.DataStructureDefinition.WebHome]] and the [[MetadataStructureDefinition>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.VersionableArtefact.MaintainableArtefact.Structure.MetadataStructureDefinition.WebHome]], it may not be sufficient for supporting the more complex associations between codes that are often found in coding schemes such as a [[classification>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]] scheme. Often, the [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] used in a [[DataStructureDefinition>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.VersionableArtefact.MaintainableArtefact.Structure.DataStructureDefinition.WebHome]] is derived from a more complex coding scheme. Access to such a coding scheme can aid applications, such as OLAP applications or data visualisation systems, to give more views of the data than would be possible with the simple [[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] used in the [[DataStructureDefinition>>doc:IMElements.AnnotableArtefact.IdentifiableArtefact.NameableArtefact.VersionableArtefact.MaintainableArtefact.Structure.DataStructureDefinition.WebHome]]. A [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] may be linked to an IndentifiableArtefact, in order to assist.
1.1	8
15.1	9	Note that a [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] is not necessarily a balanced tree. A balanced tree is where
1.1	10
15.2	11	levels are pre-defined and fixed, (i.e. a level always has the same set of codes, and any code has a fixed [[parent>>doc:IMElements.parent.WebHome]] and [[child>>doc:IMElements.child.WebHome]] relationship to other codes). A [[statistical classification>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]] is an example of a balanced tree, and the support for a balanced [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] is a subset, and special case, of [[hierarchies>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
6.2	12
15.1	13	The principal features of the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] are:
1.1	14
15.2	15	1. A [[child>>doc:IMElements.child.WebHome]] code can have more than one [[parent>>doc:IMElements.parent.WebHome]].
	16	1. There can be more than one code that has no [[parent>>doc:IMElements.parent.WebHome]] (i.e. more than one “root node”).
	17	1. The levels in a [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] can be explicitly defined or they can be implicit: i.e. they exist only as [[parent>>doc:IMElements.parent.WebHome]]/[[child>>doc:IMElements.child.WebHome]] relationships in the coding [[structure>>doc:IMElements.structure.WebHome]].
15.1	18	1. [[Hierarchies>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] may be associated to the structures they refer to, via the HierarchyAssociation.
1.1	19
3.2	20	== 8.2 Inheritance ==
1.1	21
3.2	22	=== 8.2.1 Class Diagram ===
1.1	23
10.2	24	[[image:image61.png]]
	25
1.1	26	Figure 35: Inheritance class diagram for the Hierarchy
	27
3.2	28	=== 8.2.2 Explanation of the Diagram ===
1.1	29
3.2	30	==== 8.2.2.1 Narrative ====
1.1	31
15.1	32	The [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] and //HierarchyAssociation// inherit from //MaintainableArtefact// and thus have identification, naming, versioning and a [[maintenance agency>>doc:sdmx:Glossary 2\.1.Maintenance agency.WebHome]]. The (% style="color:#e74c3c" %)Level(%%) is a //NameableArtefact// and therefore has an Id, multi-lingual name and multi-lingual description. A //HierachicalCode// is an //IdentifiableArtefact//.
1.1	33
15.1	34	It is important to understand that the [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] participating in a [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] are not themselves contained in the list – they are referenced from the list and are maintained in one or more [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]]. This is explained in the narrative of the relationship class diagram below.
1.1	35
3.2	36	==== 8.2.2.2 Definitions ====
1.1	37
15.1	38	The definitions of the various classes, [[attributes>>doc:sdmx:Glossary 2\.1.Attribute.WebHome]], and associations are shown in the relationship section below.
1.1	39
3.2	40	== 8.3 Relationship ==
1.1	41
3.2	42	=== 8.3.1 Class Diagram ===
1.1	43
10.3	44	[[image:image62.png]]
	45
1.1	46	Figure 36: Relationship class diagram of the Hierarchy
	47
3.2	48	=== 8.3.2 Explanation of the Diagram ===
1.1	49
3.2	50	==== 8.3.2.1 Narrative ====
1.1	51
15.1	52	The basic principles of the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] are:
1.1	53
15.1	54	1. The [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] is a specification of the structure of the [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]].
	55	1. The [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] are not themselves a part of the [[artefact>>doc:sdmx:Glossary 2\.1.Artefact.WebHome]], rather they are references to [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in one or more external [[Codelists>>doc:sdmx:Glossary 2\.1.Code list.WebHome]].
	56	1. The [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] of [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] is specified in HierarchicalCode. This references the [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] and its immediate child HierarchicalCodes.
1.1	57
15.1	58	A [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] can have formal (% style="color:#e74c3c" %)levels(%%) (hasFormalLevels="true"). However, even if hasFormalLevels="false" the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] can still have one or more (% style="color:#e74c3c" %)Levels(%%) associated in order to document information about the HierarchicalCodes.
1.1	59
15.1	60	If hasFormalLevels="false" the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] is “value based” comprising a [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] of [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] with no formal (% style="color:#e74c3c" %)Levels(%%). If hasFormalLevels="true" then the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] is “(% style="color:#e74c3c" %)level(%%) based” where each (% style="color:#e74c3c" %)Level(%%) is a formal (% style="color:#e74c3c" %)Level(%%) in the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]], such as those present in [[statistical classifications>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]]. In a “(% style="color:#e74c3c" %)level(%%) based” [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] each HierarchicalCode is linked to the (% style="color:#e74c3c" %)Level(%%) in which it resides. It is expected that all HierarchicalCodes at the same hierarchic (% style="color:#e74c3c" %)level(%%) defined by the +parent/+child association will be linked to the same (% style="color:#e74c3c" %)Level(%%). Note that the +(% style="color:#e74c3c" %)level(%%) association need only be specified if the HierarchicalCode is at a different hierarchical (% style="color:#e74c3c" %)level(%%) (implied by the HierarchicalCode parent/child association) than the actual (% style="color:#e74c3c" %)Level(%%) in the (% style="color:#e74c3c" %)level(%%) [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] (implied by the (% style="color:#e74c3c" %)Level(%%) parent/child association).
1.1	61
15.1	62	[Note that organisations wishing to be compliant with accepted models for [[statistical classifications>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]] should ensure that the Id is the number associated with the (% style="color:#e74c3c" %)Level(%%), where (% style="color:#e74c3c" %)Levels(%%) are numbered consecutively starting with (% style="color:#e74c3c" %)level(%%) 1 at the highest (% style="color:#e74c3c" %)Level(%%)].
1.1	63
15.1	64	The (% style="color:#e74c3c" %)Level(%%) may have CodingFormat information defined (e.g. coding type at that (% style="color:#e74c3c" %)level(%%)).
1.1	65
15.1	66	A HierarchyAssociation links an IdentifiableArtefact (+linkedObject), that needs a [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]], with the latter (+linkedHierarchy). The association is performed in a certain context (+contextObject), e.g. a [[Dimension>>doc:sdmx:Glossary 2\.1.Dimension.WebHome]] in the context of a [[Dataflow>>doc:sdmx:Glossary 2\.1.Dataflow.WebHome]].
1.1	67
15.1	68	==== 8.3.2.2 ====
1.1	69
15.1	70	==== Definitions ====
	71
3.3	72	(% style="width:901.835px" %)
	73	\|Class\|Feature\|(% style="width:564px" %)Description
15.1	74	\|[[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]]\|(((
1.1	75	Inherits from:
	76	//MaintainableArtefact//
15.1	77	)))\|(% style="width:564px" %)A [[classification>>doc:sdmx:Glossary 2\.1.Statistical Classification.WebHome]] structure arranged in (% style="color:#e74c3c" %)levels(%%) of detail from the broadest to the most detailed (% style="color:#e74c3c" %)level(%%).
3.3	78	\| \|hasFormalLevels\|(% style="width:564px" %)(((
15.1	79	If “true”, this indicates a [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] where the structure is arranged in (% style="color:#e74c3c" %)levels(%%) of detail from the broadest to the most detailed (% style="color:#e74c3c" %)level(%%).
1.1	80
15.1	81	If “false”, this indicates a [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] structure where the items in the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] have no formal (% style="color:#e74c3c" %)level(%%) structure.
1.1	82	)))
15.1	83	\| \|+[[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]]\|(% style="width:564px" %)Association to the top-(% style="color:#e74c3c" %)level(%%) [[Hierarchical Codes>>doc:sdmx:Glossary 2\.1.Hierarchical code.WebHome]] in the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	84	\| \|+(% style="color:#e74c3c" %)level\|(% style="width:564px" %)Association to the top (% style="color:#e74c3c" %)Level(%%) in the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	85	\|(%%)(% style="color:#e74c3c" %)Level\|(((
1.1	86	Inherits from
	87	//NameableArtefact//
3.3	88	)))\|(% style="width:564px" %)(((
15.1	89	In a “(% style="color:#e74c3c" %)level(%%) based” [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] this describes a group of [[Codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] which are characterised by homogeneous coding, and where the parent of each [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in the group is at the same higher (% style="color:#e74c3c" %)level(%%) of the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	90	In a “value based’ [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] this describes information about the [[Hierarchical Codes>>doc:sdmx:Glossary 2\.1.Hierarchical code.WebHome]] at the specified nesting (% style="color:#e74c3c" %)level(%%).
1.1	91	)))
15.1	92	\| \|+codeFormat\|(% style="width:564px" %)Association to the [[Coding Format>>doc:sdmx:Glossary 2\.1.Coding format.WebHome]].
	93	\| \|+child\|(% style="width:564px" %)Association to a child (% style="color:#e74c3c" %)Level(%%) of (% style="color:#e74c3c" %)Level(%%).
	94	\|CodingFormat\| \|(% style="width:564px" %)Specifies format information for the [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] at this (% style="color:#e74c3c" %)level(%%) in the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]] such as whether the [[codes>>doc:sdmx:Glossary 2\.1.Code.WebHome]] at the (% style="color:#e74c3c" %)level(%%) are alphabetic, numeric or alphanumeric and the [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] length.
	95	\|HierarchicalCode\| \|(% style="width:564px" %)A hierarchic structure of [[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] references.
3.3	96	\| \|validFrom\|(% style="width:564px" %)Date from which the construct is valid
	97	\| \|validTo\|(% style="width:564px" %)Date from which construct is superseded.
15.1	98	\| \|+[[code>>doc:sdmx:Glossary 2\.1.Code.WebHome]]\|(% style="width:564px" %)Association to the [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] that is used at the specific point in the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	99	\| \|+child\|(% style="width:564px" %)Association to a child [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] in the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	100	\| \|+(% style="color:#e74c3c" %)level\|(% style="width:564px" %)Association to a (% style="color:#e74c3c" %)Level(%%) where (% style="color:#e74c3c" %)levels(%%) have been defined for the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	101	\|[[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]]\| \|(% style="width:564px" %)The [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]] to be used at this point in the [[hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	102	\| \|/items\|(% style="width:564px" %)Association to the [[Code list>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] containing the [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]].
	103	\|[[Codelist>>doc:sdmx:Glossary 2\.1.Code list.WebHome]]\| \|(% style="width:564px" %)The [[Code list>>doc:sdmx:Glossary 2\.1.Code list.WebHome]] containing the [[Code>>doc:sdmx:Glossary 2\.1.Code.WebHome]].
1.1	104	\|HierarchyAssociation\|(((
	105	Inherits from:
5.1	106	//MaintainableArtefact//
15.1	107	)))\|(% style="width:564px" %)An association between an [[Identifiable Artefact>>doc:sdmx:Glossary 2\.1.Identifiable artefact.WebHome]] and a [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]], within a specific context.
3.3	108	\| \|+contextObject\|(% style="width:564px" %)The context within which the association is performed.
15.1	109	\| \|+linkedObject\|(% style="width:564px" %)Associates the [[Identifiable Artefact>>doc:sdmx:Glossary 2\.1.Identifiable artefact.WebHome]] that needs the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].
	110	\| \|+linkedHierarchy\|(% style="width:564px" %)Associated the [[Hierarchy>>doc:sdmx:Glossary 2\.1.Hierarchy.WebHome]].