more than 16 characteristics in an ODS key. What to do?

Hi,

I have a standar ODS (0FIGL_O10) wich is fed by 0FI_GL_10 extractor. When analisyng the data, I can see that I need more than 16 characteristics in the ODS's key. What is the correct approach to face this problems (and solve it).

thans for your advice.

Mauricio.