Data Warehouses and the Semantic Web - Data Warehouse Systems: Design and Implementation - page 543

qb:componentRequired : boolean
qb:componentAttachment : rdf:Class
qb:order : xsd:int

qb:DataStructureDefinition qb:ComponentSpecification

qb:component

qb:componentProperty

qb:structure qb:sliceKey qb:dimension

qb:attribute
qb:measure

qb:componentProperty

qb:DataSet qb:SliceKey qb:ComponentProperty

qb:dataSet qb:slice qb:sliceStructure qb:concept

qb:DimensionProperty

qb:Observation qb:Slice skos:Concept qb:AttributeProperty

qb:MeasureProperty

qb:observation qb:subSlice

sdmx:Concept

qb:CodedProperty

sdmx:FrequenceRole
sdmx:CountRole
sdmx:EntityRole
sdmx:TimeRole
sdmx:MeasureTypeRole
sdmx:NonObsTimeRole
sdmx:IdentityRole
sdmx:PrimaryMeasureRole

qb:codeList

sdmx:ConceptRole

skos:ConceptScheme

sdmx:CodeList

Fig. 14.6 Outline of the QB vocabulary

dimensions, measures, and attributes, called qb:dimension , qb:measure ,and
qb:attribute , respectively. Component specifications are linked to DSDs via
the property qb:component . For example, the schema of the HouseholdCS data
cube of Fig. 14.5 canbedefinedasfollows:

ex:Geography a qb:DimensionProperty, qb:CodedProperty .
ex:Time a qb:DimensionProperty, qb:CodedProperty .
ex:Household a qb:MeasureProperty .
ex:HouseholdCS a qb:DataStructureDefinition ;
qb:component [qb:dimension ex:Geography] ;
qb:component [qb:dimension ex:Time] ;
qb:component [qb:measure ex:Household] ;
qb:component [qb:attribute sdmx-attribute:unitMeasure] .

For clarity, we omit above the declaration of the prefixes. First, the Geography
and Time dimensions as well as the Household measure are defined. Then,
thedatacubeschema,called ex:HouseholdCS , is declared as an instance of
qb:DataStructureDefinition . Dimensions, measures, and attributes are defined
using the qb:component property and using blank nodes.
Observations, which are instances of qb:Observation , represent points in a
multidimensional data space. They are grouped in data sets by means of the
qb:dataSet property. An observation is linked to a value in each dimension
of the DSD using properties defined as instances of qb:DimensionProperty .