Logical Data Warehouse Design - Data Warehouse Systems: Design and Implementation - page 167

values for the hideMemberIf attribute are Never (the member always appears,
the default value) and IfParentName (the member appears unless its name
matches the one of its parent).
We next show how a fact (or degenerate ) dimension can be defined in
Mondrian. Such a dimension has no associated dimension table, and thus,
all the columns in the dimension are in the fact table. In the case of the
Northwind cube, there is a fact dimension Order , composed by the order
number and the order line number corresponding to the fact. To represent
this dimension, we may write:

< Dimension name= ' Order ' table= ' Sales ' >

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< Attributes >

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< Attribute name= ' Order No ' keyColumn= ' OrderNo ' >

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< Attribute name= ' Order Line ' keyColumn= ' OrderLine ' >

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< /Attributes >

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< /Dimension >

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Note that the table associated with the dimension is the Sales fact table.

5.10.3 Measures

As in Analysis Services, in Mondrian the measures are also considered
dimensions: every cube has an implicit Measures dimension (we will see this
in detail in Chap. 6 ). The Measures dimension has a single hierarchy, also
called Measures , which has a single level, in turn also called Measures .The
measures of the Sales cube are defined as follows:

< Cube name= ' Sales ' >

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< Dimensions . . . / >

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< MeasureGroups >

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< MeasureGroup name= ' Sales ' table= ' Sales ' >

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< Measures >

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< Measure name= ' Unit Price ' column= ' UnitPrice '

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aggregator= ' avg ' formatString= ' $#,##0.00 ' / >

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< Measure name= ' Sales Count ' aggregator= ' count ' / >

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...

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< /Measures >

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< DimensionLinks >

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< ForeignKeyLink dimension= ' Customer '

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foreignKeyColumn= ' CustomerKey ' / >

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< ForeignKeyLink dimension= ' OrderDate '

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foreignKeyColumn= ' OrderDateKey ' / >

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...

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< FactLink dimension= ' Order ' / >

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< /DimensionLinks >

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< /MeasureGroup >

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< /MeasureGroups >

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< CalculatedMember name= ' Net Amount ' dimension= ' Measures '

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formula= ' [Measures].[Sales Amount]-[Measures].[Freight] ' >

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