Data Source Scope - IBM Cognos User Manual

v measure allocation capabilities
v performance improvements
v integration of data from various sources

Data Source Scope

Data sources may be associated with all or part of the Cognos Transformer
Dimension Map. To make the proper associations, all column names related to the
same level in the Dimension Map must match exactly. Also, the levels with which
these source columns are associated must be either unique or fully qualified by one
or more higher levels in the hierarchy.
The scope that appears depends on the relationship between the source columns
and the levels in the Dimension Map.
Tips
v To see the scope for a data source in your model, click it in the Data Sources list
v You can change the default colors of the scope map on the Dimension Map tab
Level Derived Directly
When a level is derived directly, it takes its category values from a column in the
source. For example, this source contains columns that provide category values for
all levels. The default color is dark yellow.
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IBM Cognos Transformer Version 10.1.1: User Guide
Measures that are not normally related to some parts of the dimensional
hierarchy can have values allocated to those parts of the dimension.
For example, suppose your sales-tracking system lacks information about
staffing levels at each branch. You include a data source that provides this
information so that you can derive valuable information, such as the average
sales per employee.
When you split a single, large data source into smaller, denormalized sources,
you can shorten the processing time if the columns in all measure-containing
sources are associated with unique levels in the model. This is because Cognos
Transformer can associate such measures directly, without confirming their
context in the level hierarchy.
Cognos Transformer does not perform database joins between like-named
columns. Rather, it associates the data values in each source with the categories
that are generated from the columns. To create source data that joins database
tables, use IBM Cognos Impromptu, IBM Cognos, IBM Cognos Data Manager,
IBM Cognos Virtual View Manager, or a data access application.
and, from the Edit menu, click Show Scope. You can also right-click in the
Dimension Map or the Data Sources list.
of the Preferences property sheet on the File menu. Click the color swatch you
want to change and select a new color from the Color palette. Click OK twice.