Cognos ReportNet(TM) Readme

Cognos ReportNet 1.1 MR3 Readme
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For the remainder of this section, it is assumed that an SAP BW Query is being used as the basis
for externalizing the data, not as the basis for reporting, and with the intent of exceeding the
memory and time limitations associated with extracting data directly from an InfoCube.
SAP BW Query Requirements
First, it is not possible to externalize an arbitrary SAP BW Query. To be externalized, an SAP BW
Query must adhere to the following restrictions:
• Only a single field can be shown. Showing something such as "key and text" will result in
incorrect data.
To change what appears for a characteristic, right-click the characteristic along the edge of the
SAP BW Query and click Properties. In the Properties dialog box, set the Display As value to
Key.
It is strongly recommended that you use Key.
• To reduce data volumes, as well as the amount of aggregation performed by the SAP BW server,
it is strongly recommended that summarization for all characteristics in the query be
disabled in its property sheet.
To disable summarization for a characteristic , right-click the characteristic along the edge of
the SAP BW Query and click Properties. In the Properties dialog, set the Suppress Results
Rows value to Always.
• If at least one characteristic in an InfoQuery is displayed as something other than Key, then
summarization for all characteristics must be suppressed.
• The query must not contain the Currency/Unit characteristic.
• None of the characteristics may be assigned a display hierarchy, either explicitly or by a variable.
• If a characteristic is included in an SAP BW Query as a free characteristic, no values will
appear for that characteristic in the key figures extract.
A filter on a free characteristic acts as a filter on the data returned by SAP BW. It is an efficient
mechanism for defining a subset of an InfoCube.
Such a filter may also be applied to a characteristic along an axis of an SAP BW Query, in
which case the filtered values appear in the key figures extract.
• All key figures in the SAP BW Query must be numeric.
• The values of each key figure should be in a single currency since currency information is not
carried forward into a CSV extract. A variable should not be used to drive the assignment of a
target currency.
• Include in the SAP BW Query only those characteristics which are to be extracted using Framework
Manager. Including unnecessary characteristics increases the volume of data transferred
from SAP BW, thus affecting performance.
Framework Manager Considerations
When extracting the key figure query subject from an SAP BW Query, the Extract Size property of
the data source is used to control the amount of data retrieved from the SAP BW server at one
time. The behavior in this case is slightly different than that described earlier in this topic. In this
scenario, the setting has no affect on the SAP BW server, but it does limit the amount of memory
allocated at any one time by Framework Manager to retrieve the data.
It is important to realize that filters defined on the key figures query subject are not enforced when
extracting data from an SAP BW Query. To obtain performance benefits of extracting data from
an SAP BW Query, filters must be defined in an SAP BW Query.
In addition, any calculations defined within the key figures query subject are ignored. These may
be defined either within the SAP BW Query in BEx, or in a model query subject in Framework
Manager.
Each characteristic extracted must contain at least one query item from the lowest level of its hierarchy
(if there is one) to provide linkage with the key figures extract.
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