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with a variable. Thus, by choosing an appropriate characteristic, the key figures
dimension can be extracted without exceeding the memory restrictions of either the
client or server. Memory caches on the client and server are flushed after each
query.
If a presentation hierarchy is used to drive the creation of extract sections, it is
important that the values for a variable be obtained from a single level in the
hierarchy, otherwise the extract will contain data summarized at different levels. To
restrict the values for a variable to a single level of a hierarchy, edit the Level
Restriction of the variable in Framework Manager. For example, using a value such
as "2:2" indicates that only values from the second level of the hierarchy are to be
used (level 0 is the root of a hierarchy).
In the presence of an SAP BW query with one such variable, the value of the
variable is reset after each query.
If an SAP BW query contains anything more than a single variable, or one that is
defined differently than described above, Framework Manager does not attempt to
use a variable to break the extraction of the key figures dimension into smaller
sections.
Workaround for Problems Encountered While Externalizing
When externalizing a data source from Framework Manager, you may encounter
an authentication error if
v
the model is published to Content Manager
v
externalizing the data takes longer to perform than the timeout period assigned
to passports within IBM Cognos Configuration
Users are not prompted to re-enter their authentication credentials.
If an error occurs, the externalized data is still complete and valid. However, if the
modeler chooses to actually publish the model, the modeler must re-authenticate
and re-publish the model, but without externalizing the data.
Another solution is to publish the model to the network, in which case the
authentication error does not occur.
Building PowerCubes from SAP BW Data
You can build IBM Cognos PowerCubes from SAP BW data. There are guidelines
to consider for both Framework Manager and Transformer.
For more information, see “Framework Manager Guidelines” and “Transformer
Guidelines” on page 354.
Framework Manager Guidelines
When externalizing data for the purpose of creating one or more PowerCubes,
keep these considerations in mind.
v The extract of each characteristic must have a common key query item that is
equivalent to a surrogate key query item in the key figures extract.
v
For an extract based on an SAP BW query, it is strongly recommended that all
characteristics be displayed as Key in the SAP BW query.
v
If a characteristic does not have a presentation hierarchy, or a new one is
desired, extract one or more query items that can form the basis for levels in a
hierarchy.
Appendix E. Guidelines for Working with SAP BW Data for Use in Transformer
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