In OLAP metadata, a dimension is a structure, often composed of one or more hierarchies, that categorizes data. Several distinct dimensions, combined with measures, enable end users to answer business questions. Commonly used dimensions are Product, Time, and Geography.
Each item in a dimension is a dimension member. For example, January 2001, February 2001, March 2001, Quarter 1 2001, and the year 2001 are likely members of the Time dimension.
To organize dimension members that represent hierarchical relationships, dimensions have hierarchies. A dimension can have more than one hierarchy. One hierarchy must then be the default hierarchy.
Dimensions can also have attributes, which describe characteristics of members. For example, a Product dimension might have a Color attribute.
An MDDimension
represents a dimension in the MetadataManager. An MDDimension
extends MDFolder
. As an MDFolder
, an MDDimension
contains any attributes and hierarchies that have been defined for the dimension.