[birt-report-designer-dev] How to apply aggregation on aggregation in a

["kapil sakhuja" <kapil_sakhuja@xxxxxxxxxxxxxx>]

Hi,
 
I am designing a BIRT report using BIRT 2.3.1 using scripted data source. My BIRT report consists of table which contains the following columns: Frequency, FrequencyPercent, CumulativeFrequency, CumulativePercent. The columns stated above are dependent upon each other, e.g. FrequecencyPercent is based on Frequency, CumulativeFrequency is based on Frequency and CumulativePercent is based on FrequencyPercent/CumulativeFrequency.

There are two scenarios to be dealt with:
1) No grouping of data. The entire data is placed in a one(1) table without any grouping.
2) The data is grouped by another data set output column.

To calculate CumulativePercent, i am using an aggregate function on on FrequencyPercent column,, using the aggregation builder, and on FrequencyPercent column itself has been computed using the aggregation builder (lets call this 'aggregation on aggregation'). This works in scenario # 1 above, but in scenario # 2, the CumulativePercent column which has 'aggregation on aggregation', does not show any values.

Any idea on why is this not working and how can i get it to work?

Thanks,
Kapil

"There are only 10 kinds of people in this world, ones who understand binary and others who dont."