Dimensional Usage Extensions Specs

Reference tables for this spec are located at Dimensional Usage Spec Schema Table

With Dimensional Usage Extensions specs, you can specify extended relationships between a measure group and a dimension. In the example that follows, the spec establishes a relationship between the measure group Revenue and the Event Extend dimension. For more information about Dimensional Usage, see Microsoft's MSDN article at Defining Dimension Usage Relationships.

Once processed, Dimensional Usage Extensions specs establish use of a dimension by a measure group. Dimensional Usage Extensions specs do not create a dimension. To extend the cube to include another dimension, use a Dimension Extensions spec. For more information see Dimensions Extensions Specs.

Dimensional Usage is defined for a particular BBDW OLAP cube. As such, you can identify that cube within the spec as <Cube>BBDW</Cube>, replacing BBDW for the name of the cube. DimensionID refers to the dimension in the cube. DimensionID must be for an existing Dimension or a defined Dimension Extension. In DimensionName, you define a name to use for the Dimension as seen from the item that uses it.

Within MeasureGroupRelationships, you define relationships between Measure Groups and Dimensions. You establish the type of relationship provide ID attributes to map the relationship.

The type for a dimensional usage is indicated within <RelationshipType></RelationshipType>. Values can be Regular, Fact, and ManyToMany:

With relationship types of Regular, the dimensional usage establishes a regular relationship between a dimension and a measure group. For more information, see Microsoft's MSDN article at Defining a Regular Relationship and Regular Relationship Properties.

With relationship types of Fact, the dimensional usage establishes a relationship between a dimension and a measure group. For more information, see Microsoft's MSDN article at Defining a Fact Relationship and Fact Relationship Properties.

With relationship types of ManyToMany, there is an intermediate fact table that joins to a dimension table to establish the relationship between the dimension and the measure group. For more information, see Microsoft's MSDN article at Defining a Many-to-Many Relationship and Many-to-Many Relationship Properties.

Dimensional usage specs are discussed in greater detail in BBDW OLAP Extensions: Advanced Dimensional Usage.

A Dimensional Usage extensions spec looks like this:

<DimensionalUsageDeploymentInfo>
  <Cube>BBDW</Cube>
  <DimensionID>Event Extend</DimensionID>
  <DimensionName>Event Extend</DimensionName>
  <MeasureGroupRelationships>
    <MeasureGroupRelationship>
      <RelationshipType>Regular</RelationshipType>
      <MeasureGroup>Revenue</MeasureGroup>
      <MeasureGroupRelatedColumn>EVENTDIMID</MeasureGroupRelatedColumn>
      <DimensionKeyAttributeID>EVENTDIMID</DimensionKeyAttributeID>
    </MeasureGroupRelationship>
  </MeasureGroupRelationships>
</DimensionalUsageDeploymentInfo>