Multiple Hierarchies in a Cube Dimension
A dimension can have multiple hierarchies. For a dimension that includes multiple hierarchies, the corresponding axis of the cube contains one segment for each member of the lowest level in each hierarchy.
Consider the following theoretical cube:
Members of cube 'theoretical':
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...
Dimensions
...
Sales Date
H1
Sales Year
Sales Period
Sales Date
H2
Sales Quarter
...
The Sales Date dimension contains two hierarchies. The H1 hierarchy has three levels:
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The Sales Year level. For example, a members of this level is 1990.
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The Sales Period level. For example, a members of this level is Jan–1990.
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The Sales Date level. For example, a members of this level is Jan 3 1990.
The other hierarchy contains only one level.
In this case, the Sales Date axis contains one segment for each member of Sales Date and one segment for each member of Sales Quarter. For example:
(For reasons of space, the picture of the cube is not divided into tuples.)
When a query uses, for example, the Sales Quarter level, the system uses the appropriate part of this axis and accesses the requested tuples.