A virtual dimension is an alias of either
a dimension from one of the two cubes that the virtual cube is based
on, or the result of dimension merging in the virtual cube. You can
create a virtual dimension for a virtual cube in the Design Studio.
Before you begin
- Start the Design Studio
- Create a virtual cube.
About this task
You
can create virtual dimensions to rename dimension from the two dependent
cubes of the virtual cube, so that the dimensions can be merged in
a way you want.
Procedure
To
create a virtual dimension in a virtual cube:
- In the Data Project Explorer, right-click the virtual cube
that you want to add a virtual dimension to, and click Add
Virtual Dimension. A window opens with a list of available
dimensions from the two cubes that the virtual cube is based on. Dimensions
that are already referenced by other virtual dimensions of this virtual
cube are not displayed.
- Select one or more dimensions, and click OK.
The virtual dimension is created with an automatically generated name. Make sure that you can see the Properties view.
If you cannot see the Properties view, click . You might need to select the OLAP object from the
Data Project Explorer again.
- In the Properties view, modify the
name, the source dimension, or the default member of this virtual
dimension. You can also add calculated members or select whether to
hide this virtual dimension in the virtual cube. If a dimension is
hidden, it will not be available for queries that are run against
the virtual cube. For more details on the properties of
a virtual dimension, refer to Virtual dimension properties.
Assume that you have a virtual cube called CA Sales,
which is based on cube Sales from Northern CA and cube Sales
from Southern CA. The Sales from Northern CA cube has three
dimensions NorthCA Regions, Products, and Time.
The Sales from Southern CA cube also has three dimensions, SouthCA
Regions, Products, and Time. If you don't create
virtual dimensions for the virtual cube, you will have four dimensions
after the two cubes are merged, namely, NorthCA Regions, SouthCA
Regions, Products, and Time. Because both the NorthCA
Regions dimension and the SouthCA Regions dimension contains
geographical information with similar levels, you might want to merge
these two dimensions into Regions dimension. To do this, you
create two virtual dimensions that have the same name Regions,
and have NorthCA Regions and SouthCA Regions as the
source dimensions.
You can delete a virtual dimension. When you delete a
virtual dimension, all of its virtual elements, including the virtual
members and MDX calculated members, are also deleted.