Specify How Missing Values Appear - IBM Cognos User Manual

Although values for measures calculated after rollup require less storage space,
time-state rollup cannot be performed on After Rollup calculated measures.
Auto-partitioning is not used when a model contains Before Rollup measures,
which can be detrimental to run-time performance. To allow auto-partitioning to
proceed, we recommend that you use calculated columns instead of Before Rollup
measures wherever possible.
Similarly, although there is no consolidation of Before Rollup measures, you can
use calculated columns to perform consolidation instead. The measure data is then
consolidated as each row is read into the work file.
Procedure
1. Open the property sheet for the calculated measure and click the Rollup tab.
2. In the Regular timing box, click Before Rollup or After Rollup and click OK.

Specify How Missing Values Appear

Cognos Transformer uses default measure settings for missing values to determine
how null results are handled.
The default setting for missing values is NA; when the default setting is used, na
is inserted into your OLAP reporting component for the missing values. In releases
of Cognos Transformer prior to version 8.3, the default setting for missing values
was Zero; when that default setting was used, zeros were inserted into the OLAP
reporting component for the missing values.
The default setting can also affect the values that are stored and shown for
calculated measures. When a calculated measure is based on a measure for which
the Missing value setting is Zero, and there is no data for this second measure, the
calculation will be valid because the missing information is treated as a zero.
However, when the missing value setting is the Cognos Transformer default, NA,
the calculation result will be invalid because the missing information is treated as a
null value and not a zero.
When models created with previous versions of Cognos Transformer are upgraded
to Cognos Transformer version 8.x and later, measures that have the missing value
settings set to the Cognos Transformer version 7.x default (Zero) will not be
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IBM Cognos Transformer Version 10.1.1: User Guide
Timing
After Rollup
Before Rollup
Operation sequence
1 Regular rollup takes place on all measures.
2 Time state rollup takes place.
3 Allocated measures are calculated.
4 Calculations are performed on calculated measures.
1 Calculations are performed as the cube is created.
2 Regular rollup takes place on all measures.
3 Time state rollup takes place.
4 Allocated measures are calculated.