I seem to be on a ride running into numerous defects over the last couple of months. The latest one being similar duplicate queries generated by Cognos in a particular scenario.
As can be seen from the screenshot, Cognos generates 2 queries with no differences and both having the same name.
This happens in the below scenario:
When you have a singleton object before all other Objects in the report.
And when you have Prompt Macro as the first filter in the first object of the report.
And if you have value prompts after the singleton but before the first chart/list/crosstab object, then these queries get duplicated as shown below:
When each query counts towards performance, this isn't good.
So the work-around is to have a Required prompt without macros as the first prompt in a list/crosstab/chart object. If one doesn't exist create a dummy required filter to get around-this.
As can be seen from the screenshot, Cognos generates 2 queries with no differences and both having the same name.
When you have a singleton object before all other Objects in the report.
And when you have Prompt Macro as the first filter in the first object of the report.
And if you have value prompts after the singleton but before the first chart/list/crosstab object, then these queries get duplicated as shown below:
So the work-around is to have a Required prompt without macros as the first prompt in a list/crosstab/chart object. If one doesn't exist create a dummy required filter to get around-this.