Creating Restrictions in BEx query designer for (1-a), where a is variable.

Dear All,

>> Suppose for the variable in the BEx query designer, I've created restriction for 0FISCPER to the variable 0P_PER (as 0P_PER-1) by right clicking 0P_PER3, from that a dialog box appears. In that I've selected 0P_PER3 and then clicked on offset variable and when I set the offset variable, it works for (0P_PER-1.etc, 0P_PER+1,etc..)

But if I want to have (1-0P_PER), then plz tell me how to define this restriction?

Plz explain me the steps to perform (1-0P_PER) restriction in BEx query designer in BW1.

I'm using SAP BI 7.2 gui.

Expecting your reply soon,

with Regards,

Jerald