Prompt forced to be as required even if we select 'optional'

[ejaycognos]

here is the scenario .. In a crosstab report, need to dynamically change the column based on prompt , so created a calculated column 'x' and placed in the report as crosstab row.

x=if(?prompt1? is not null and ?prompt2? is null) then 'column1' else if (?prompt2? is not null and ?prompt3? is null) then ('column2') else NULL.

ie., if prompt 1 is selected then,

Jan Feb MArch
column1 xxxxxxxxx(measures)
xxxxxxxxx

if prompt 2 is also selected then,

Jan Feb March
column 2 xxxxxxxxx
xxxxxxxxx

For this , dynamic column , I just used a simple nested if statement to dynamically change the column based upon the prompt value.(see logic calculation above)


Now , when I need from prompt 3 optional , it is forcing me to select upto last level .. level 5 ,I need prompt 1 and 2 as required rest all as optional.

how to do this ??