Hi Christoph,
Still confusing for me, sorry.
You have on source a column in format YYYYMM and a calculated column YYYYMM_36 that was based on YYYYMM converted to date back to 36 months ago and converted back to string. Right?
Now if want filter what is parameter >= YYYYMM_36 and <= YYYYMM. Is what you want?
What is the doubt? How to use parameters?
How are you you calling this view? You put the filter on WHERE clause or are you passing it by placeholder?
Regards, Fernando Da Rós