IBM Cognos, Руководство пользователя

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Note: The Cloak , Summarize , and Suppress options do not remove data from the
cube. Therefore, even if many categories are omitted, there is no corresponding
decrease in cube size.
You create dimension and custom views in much the same way, but you must
configure security before you include custom views in your model. You can then
select security objects from the available list, define a custom view using any
option except
Suppress , and associate the view with a cube in the PowerCubes
list. When a user opens the cube in PowerPlay or one of the IBM Cognos studios,
the system verifies that the user has the necessary access permissions for the
secured data before showing the portion of the cube defined in the custom view.
You can create cubes for different audiences based on dimension views, and
further restrict access by applying custom views to selected cubes in the set.
However, certain combinations may not work well with your partitioning scheme,
thereby lengthening cube build times. One workaround is to create several smaller
cubes, each using different dimension views, rather than create one large cube that
has an unacceptably long build time.
Create a Dimension View
When you need to develop OLAP reporting solutions for diverse groups in your
organization, you can create dimension views and apply them to the cubes in your
model, thereby creating customized cubes and drill-through reports to meet the
needs of each group.
For example, suppose you want to create a different cube for each regional sales
manager that contains the transaction details for their region and summarized
values for the other regions. You begin by defining an Asia Pacific Region View
that summarizes the data for Northern, Central, and Southern Europe and the
Americas, while retaining the details for the Asia Pacific region.
You apply your dimension view by selecting the View option on the Dimensions
tab of the property sheet for the PowerCube object. You then repeat these steps to
create the required dimension views in your other regional cubes.
The resulting regional cubes contain detailed data for each manager of that region
and summarized information for the other regions.
Tip: Instead of creating a separate dimension view for each category in a level,
you may want to create a cube group based on that target level, if this is easier to
Chapter 6. Creating PowerCubes
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