Refining Your Model - IBM Cognos User Manual

Refining Your Model

Based on your paper prototype, you create the Dimension Map for your new
model in Cognos Transformer. You begin with one data source. You can enhance
the business value of your model later, by adding more sources or manipulating
the data derived from the existing data sources.
Suppose you are initially lacking information about the staffing levels in each
branch. You can either add another data source to provide this information or use
the Category Count feature of Cognos Transformer to provide this detail. The
resulting cube and OLAP reports can then deliver value-added information about
the average sales per employee.
Models can contain any combination of the following:
v regular measures, or the numeric fact data found in a transaction file
v calculated measures, or numeric data calculated from other measures,
v category counts, or the number of categories in a unique level for which the
v calculated categories, whereby calculated expressions apply directly to any
v calculated columns, whereby new data is based on values calculated from other
Use the following checklist to help refine your model:
v Add special categories to enable quicker data access.
v Add drill-down paths to provide more detail.
v Allocate measures to other levels or dimensions.
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IBM Cognos Transformer Version 10.1.1: User Guide
Order date
Year
Quarter
Month
mathematical operators, and numeric constants
measure values are not zero or missing
measure
columns, functions, constants, and calculated columns
Group your data based on attributes that may be contributing to the success of
your enterprise, such as product color or customer income.
A dimension normally consists of a single drill-down path with one or more
drill-down levels, representing the hierarchical organization of the information.
However, you can further subdivide your dimensions, so your report users can
analyze their data at different levels of detail.
There are no restrictions on the number of levels and drill-down paths that you
use in a dimension. However, all alternate drill-down paths must converge at a
common unique level and, for performance reasons, it is best to keep a 1:10 ratio
or less between the categories in each level.
For information on drill through using categories from alternate drill paths, see
the Administration and Security Guide.
If your model uses multiple data sources, consider allocating measures to levels
or dimensions with which they are not normally associated. Allocation can
provide you with new insights into your data. For example, you can associate
resource-related data to financial data.
Products
Product Group
Product Class
Product Name
Product No
Locations
Region
Office
Sales Rep