Who can help me?

I use with the following syntax:

do (_genxtab) with 'final1',.t.,.f.,.t.,1,2,3,.t.,0

And I get cursor 'final1'.
If the values for all the lines of specific category is 0, I don't get column for this category in the cursor.
The problem is that if I try later to get data from this field (in code or report field) I get error message.
How can I resolve the problem by forceing 'genxtab' to include columns even all the values is 0.
Big thank you for helping me