Filter column based on another column - OBIEE 11g

Question

Hi, I have kind of a strange requirement. I'm trying to build a dashboard that lets a user see data for the current day, last week, last month, or last year. I'm going to create a presentation variable called "date_range" where the user can choose one of those 4 options.
Based on this, I've defined a column in answers with the following formula:
cast
case
when 1 = 0 then "Query Time"."Date"
when @{date_range}{'Day'} = 'Day' then Current_Date
when @{date_range}{'Week'} = 'Week' then TIMESTAMPADD(SQL_TSI_DAY, -7, CURRENT_DATE)
when @{date_range}{'Day'} = 'Month' then TIMESTAMPADD(SQL_TSI_DAY, -30, CURRENT_DATE)
when @{date_range}{'Day'} = 'Year' then TIMESTAMPADD(SQL_TSI_DAY, -365, CURRENT_DATE)
else TIMESTAMPADD(SQL_TSI_DAY, -10000, CURRENT_DATE)
end as DATE
Based on the 4 presentation variable, this should give the proper "start date" of when to pull data.
Now I've added the actual date column from the date dimension. But I need to put a filter on the date dimension date column that says it's greater than or equal to the calculated column above. How do I do that?
Thanks,
Scott

Answer 1

I always expect what you're expecting, but you can't filter a column on another column. The solution is just to write one formula that returns a literal, so it will be
case when (your date column) >= (your long formula) then 'Y' else 'N' end
Then filter that column on 'Y'.
Regards,
Robert